OF lU RY AT URBANA-* .PAIGN AGRICI '"" NOTICE: Return or renew all Library Materials! The Minimum Fee for each Lost Book is $50.00. The person charging this material is responsible for its return to the library from which it was withdrawn on or before the Latest Date stamped below. Theft, mutilation, and underlining of boolcs are reasons for discipli- nary action and may result in dismissal from the University. To renew call Telephone Center, 333-8400 UNIVERSITY OF ILLINOIS LIBRARY AT URBANA-CHAMPAIGN L161— O-1096 Digitized by the Internet Archive in 2011 with funding from University of Illinois Urbana-Champaign http://www.archive.org/details/soilsurveymontgo86down a- SOIL SURVEY I/NIVERSITY OF ILLINOIS 'AGRlCmURE LIBRARY . In IDGi, soybeans were grown on Q-t.T percent of the total acreage in "farms. Oats are no longer an important crop, though they foi-merly were gi-own on a large acreage. The acreage in hay crops, which were also formerly grown extensively, has declined in recent years. In 1904, only 3.9 percent of the total acreage in farms was used to grow al- falfa and other hay crops. The acreage in pastures has also declined. Pastures occupied 16.8 percent of the total acre- age in farms in 1904. Much of the decline in the acreage in oats, hay, and pas- ture has apparently been caused by increased production of soybeans and by the decrease in the number of horses and nuiles in the county. In 19G0, over 864 horses and mules were in the county. jNIost of the horses are kept for pleasure rather than for furnishing power on farms. The raisiiTg of hogs is the largest livestock enterjjrise in the county. In 1964, a total of 152,016 head of hogs and pigs was reported on farms. The nunaber of milk cows has decreased during the i^ast few years, and only 4,572 milk cows were reported on farms in 1964. The number of other cattle, however, rose from 19,991 to 38,845 during the pe- riod 1950 to 1964. A total of 5,664 sheep was in the county in 1964, as compared to 18,026 in 1930 and 8,037 in 1959. In the same year, the total number of chickens 4 months old and older was 175,008, as compared to 257,539 in 1959 and 333,864 in 1930. Transportation and Industrial Development Se\'eral railroads j^ass through this county. Tlie first, built in 1855, passed through Litchfield, Butler, Hillsboro, and Nokomis and permitted increased exports of grain and livestock to St. Louis and to Terre Haute, Ind. Later it encouraged the development of coal mining and manufac- turing. A network of paved primary highways and of im- proved secondary roads provides access to all parts of the county throughout the year. In this county coal mining is second only to farming in importance. The first coal mine was developed at Litch- field between 1867 and 1874. The production of coal in- creased rapidly until World War I, and it is still an im- portant industry. Manufacturing is concentrated primarily in Litchfield, where such items as shoes, radiators, and milk products are manufactured. Several mutual insurance companies have home offices in Hillsboro. How This Survey Was Made Soil scientists made this survey to learn what kinds of soils are in jNIontgomery County, wliere they are located, and how they can be used most effectively. Thej' went into the area knowing they likely would find many soils they had already seen, and ])erhaps some they had not. As they worked in the county, they observed steepness, length, and shai^e of slopes; size and speed of streams; kinds of native plants or crops; kinds of rock; and many facts about the soils. They dug many holes to expose soil profiles. A pro- file is the sequence of natural layers, or horizons, in a soil ; it extends from the surface down into the parent material that has not been changed much by leaching or by roots of plants. The soil scientists made comparisons among the profiles they studied, and they compared these profiles with those in comities nearby and in places more distant. They classi- fied and named the soils according to nationwide, uniform procedures. To use this survey efficiently, it is necessary to know the kinds of groupings most used in a local soil classification. Soils that have profiles almost alike make up a soil series. Except for difterent texture in the surface layer, all the soils of one series have major horizons that are similar in thickness, ai'rangement, and other important character- istics. Each soil series is named for a town or other geo- graphic feature near the place where a soil of that series was first observed and mapped. A'irden and Cowden, for example, are the names of two soil series. All the soils in the United States having the same series name are essen- tially alike in those characteristics that go with their be- havior in the natural, untouched landscape. Soils of one series can differ somewhat in texture of the surface soil and in slope, stoniness, or some other characteristic that afl'ects use of the soils by man. ]\Iany soil series contain soils that differ in texture of their surface layer. According to such differences in tex- ture, separations called soil types are made. Within a series, all the soils having a surface layer of the same tex- MONTGOMERY COUNTY, ILLINOIS tiire belong; to one soil type. Shiloh silty clay loam and Shiloh silt loam are examples of two soil types. Sliiloh silt loam has a profile like that of Shiloh silty clay loam, except that it has been covered during floods by a layer of silt loam. Some soil types vary so much in slope, degree of erosion, or some other feature affecting their use, that practical suggestions about their management could not be made if they were shown on the soil map as one unit. Such soil tyi)es are divided into phases. The name of a soil phase indicates a feature that affects management. For example, Harrison silt loam, to 2 percent slopes, is one of several phases of Harrison silt loam, a soil type that ranges from nearly level to sloping. One soil type, Shiloh silty clay loam, has a recent deposit of silt loam over its normal sur- face layer of silty clay loam. This soil has been named Shiloh silt loam, overwash. After a guide for classifying and naming the soils had been worked out, the soil scientists drew the boundaries of the individual soils on aerial photographs. These photo- graphs show streams, woodlands, buildings, field borders, trees, and other details that greatly help in drawing boundaries accurately. The soil map in the back of this survey was prepared from the aerial photographs. The areas shown on a soil map are called mapping units. On most maps detailed enough to be useful in planning management of farms and fields, a mapping unit is nearly equivalent to a soil type or a phase of a soil type. It is not exactly equivalent, because it is not practical to show on such a map all the small, scattered bits of soil of some other kind that have been seen within an area that is doniinantly of a recognized soil type or soil phase. In preparing some detailed maps, the soil scientists have a problem of delineating areas where different kinds of soils are so intricately mixed and so small in size that it is not practical to show them sejDarately on the map. Therefore, they show this mixture of soils as one mapping ruiit and call it a soil complex. Ordinarily, a soil complex is named for the major kinds of soil in it, for example, Cisne-Huey complex. Also, in some places two or more soils are mapped in a single unit, if the differences between the soils are too small to justify separation, though these soils occur separately. This unit is called an undifferenti- ated soil group or undift'ei-entiated unit. An example of such a unit is Hickory and Negley loams, 15 to 35 percent slopes. Furthermore, on most soil maps, areas are shown that are so I'ocky, so shallow, or so frequently worked by wind and water that they are not classified in a soil series. These areas are shown on a soil map like other mapping units, but they are given descriptive names, such as Gul- lied land, and are called land types. While a soil survey is in progress, samples of soils are taken, as needed, for laboratory measurements and for engineering tests. Laboratory data from the same kinds of soils in other places are assembled. Data on yields of crops imder defined practices are assembled from farm records and from field or plot experiments on the same kinds of soils. Yields under defined management are estimated for all the soils. But only part of a soil survey is done when the soils have been named, described, and delineated on the map, and the laboratory data and yield data have been assem- bled. The mass of detailed information then needs to be organized in a wav that it is readilv useful to different groups of readers, among them farmers, managers of woodland, engineers, and homeowners. Grouping soils that are similar in suitability for each specified use is the method of organization commonly used in soil surveys. On the basis of yield and ])ractice tables and other data, the soil scientists set up trial groups, and then test them by further study and by consultation with farmers, agrono- mists, engineers, and others. Then, the scientists adjust the groups according to the results of their studies and consultation. Thus, the groups that arc finally evolved reflect up-to-date knowledge of the soils and their be- havior under present methods of use and management. General Soil Map The general soil map at the back of this survey shows, in color, the soil associations in Montgomery County. A soil association is a landscape that has a distinctive pro- portional pattern of soils. It normally consists of one or more major soils and at least one minor soil, and it is named for the major soils. The soils in one association may occur in another, but in a different pattern. A map showing soil associations is useful to people who want a general idea of the soils in a county, who want to compare different parts of a county, or M'ho want to know the location of large tracts that are suitable for a cei'tain kind of farming or other land use. Such a map is not suit- able for planning the management of a farm or field, because the soils in any one association ordinarily differ iji slope, depth, drainage, and other characteristics that affect management. The nine soil associations in J\Iontgomery County are described in the following pages. They are shown on the colored map at the back of this soil survey. 1. Virden-Herrick Association DcD'k-colored, fOOily dralnrd aiuJ xnin'firlxiif [inorhj drained soils on ufland -flats This soil association consists of nearly level, dark- colored soils on a loess-covered drift plain. Th.e soils are naturally poorly drained or somewhat poorly drained. Their drainage has been improved enough, however, that good crops ai'e produced. The association occupies about 20 percent of the county. About 50 percent of this association consists of poorly drained Virden soils, and about 45 percent consists of somewhat poorly drained Herrick soils on upland flats. The Virden soils generally have a surface layer of black silty clay loam and a subsoil of gray silty clay loam. The Herrick soils have a surface layer of black or very dark gray silt loam and a subsoil of silty clay loam. Poorly drained Harvel, Ebbert, and Piasa soils, and moderately well drained Plarrison soils, occupy about 5 percent of this association. The Harvel soils, in low areas, have a profile similar to that of the Virden soils, except that their surface layer is underlain by a layer of silt loam. The Ebbert soils have a profile similar to that of the Her- rick soils, but they are more poorly drained than the Her- rick soils and generally have a more grayish subsurface layer. The Piasa soils occur in a few snuill areas with the Herrick soils but are lighter colored than those soils. The Hari'ison soils are on knolls and ridges. 6 SOIL SURVEY All of the soils except the Piasa have moderate to mod- erately slow permeability, are fertile, and have high avail- able moisture capacity. The Piasa soils coiitain a large amount of exchangeable sodium (slickspots), have very slow permeability, and have moderate available moisture capacity. They are less suitable for the crops connnonly grown in the county than the other soils of this association. Almost all of this association is used for com, soybeans, wheat, oats, and meadow. Corn and soybeans are the crops grown the most extensively. 2. Herrick-Harrison Association Level to sloping^ dark-colored, somexoliat poorly drained to moderately well drained soils This soil association is in the northwestern and north- central parts of the county in areas where streams are slightly entrenched in the loess-covered glacial till plain. It occupies about 4 })ercent of tlie county. Herrick soils occupy about 50 percent of the association, and Harrison soils, about 40 percent (fig. 2). Both the Herrick and Harrison soils have a surface layer of dark- colored silt loam and a subsoil of silty clay loam. The Her- rick soils have a grayish subsoil that is mottled with brown or yellowish brown. Their drainage needs to be improved if open ditches and tile drains have not already been in- stalled. Tlie Harrison soils commonly have a brown sub- soil, which normally indicates good drainage. In most places they need some protection from water erosion. The soils of both series have high available moisture capacity and are well suited to the crops connnonly grown. Perme- ability is moderately slow or moderate. Vii'den, Ebbert, Piasa, and Velma soils occupy about 10 percent of this association. These soils, except for the Velma, are level or nearly level. The Velma soils are slop- ing and are adjacent to the larger streams. If the soils of this association are properly managed, they ai'e well suited to the crops commonly grown in the county. Corn and soybeans are the crops grown most ex- tensively. Wheat, oats, clover, and alfalfa are grown to a lesser extent. Figure 2. — Principal soils of association 2 and their relationship to one another. MONTGOMERY COUNTY, ILLINOIS 3. Oconee-Douglas-Pana Association Strongly doping to gently sloping^ dark colored and mod- erately dark colored, well-dramed and somewlmt poorly drained soils on ridges and knolls This soil association consists of rolling areas of loess- covered glacial moraines. It is mainly in the eastern part of the connty, but one area is in the central part, near the town of Butler. Strongly sloping or moderately sloping, dark-colored Douglas and Pana soils are at the highest elevations on the tops of the ridges and on the upper side slopes (fig. 3) ; gently sloping, moderately dark colored Oconee, Tamalco, and Chauncey soils are on the lower side slopes; and areas of nearly level Cowden, Ebtei-t, and Shiloh soils are between the ridges and knolls. The Shiloh soils are in depressions formerly occupied l)y shallow lakes. The association occupies about 4 percent of the county. Oconee soils occupy about 60 percent of this association. They have a surface layer of very dark gray to dark gray- ish-brown silt loaan and a subsurface layer of grayish- brown silt loam. An abnipt boundary separates the sub- surface layer from a slowly permeable subsoil of mottled heavy silty clay loam. Douglas soils occupy about 15 percent of the association, and Pana soils, about 3 percent. The Douglas and Pana soils have a dark-browai or veiy dark grayish-brown sur- face layer and a bi'own subsoil. The Douglas soils, however, developed in loess and have a surface layer of silt loam and a sxibsoil of silty clay loam. The Pana soils, developed in glacial drift., contain some gravel, and have a surface layer of loam and a subsoil of clay loam. Both the Douglas and Pana soils are well drained, but the Douglas soils have moderate permeability and the Pana soils have moderately rajMd permeability. Minor soils — the Tamalco, Cowden, and Shiloh — occupy much of the remaining acreage in the association, but Chauncey and Ebbert soils occupy small acreages. The Tamalco soils liave a profile somewhat similar to that of the Oconee soils, but their subsoil is alkaline in the lo'wer part and contains a large amount of excliangeable sodiinu. The Cowden soils have a moderately dark colored surface layer and a slowly permeable siibsoil of grayish silty clay loam. The Shiloh soils have a surface layer of veiy dark Figure 3. — Principal soils of association 3 and their relationship to one another. 294-384 — 69 2 8 SOIL SURVEY grayisli-ln'OAvn silt loam or black hea^'v silty clay loam and a subsoil of black or very dark gray siltj- clay loam to silty clay. Tliej^ have naturally poor drainage, but drainage has been improved. (reneral farming and dairy farming are predominant, and corn, soybeans, wheat, clover, alfalfa, and bluegrass pasture are the principal crops. Erosion is a hazard throughout most of the association, but terraces and grassed waterways are used to help to protect the soils. Also, crops are rotated and the soils are generallj- farmed on the contour. 4. Herrick-Piasa Association Level, dark colored and moderately dark colored soils that are on upland divides and that have a moderately sloivly or very sloxoly permeahle suhsoil This soil association is on broad upland divides that are mainly level or nearly level but that contain a few depres- sions. It occupies about 15 percent of the county. Intermingled areas of Herrick and Piasa soils make up about 80 percent of the acreage in the association. The Herrick soils have a dark-colored surface layer, and the Piasa soils have a moderately dark colored one. Because of this difference in color, the intricate pattern in which these soils occur can be easily seen in plowed fields after heavy rains in spring. Both the Herrick and Piasa soils have developed in loess and have a subsoil of silty clay loam. Unlike the Herrick soils, however, the Piasa soils have an alkaline subsoil that is high in content of ex- changeable sodium. Their subsoil is much less permeable and nearer the surface than the subsoil of the Herrick soils. The luifavorable characteristics of their subsoil make the Piasa soils not so well suited to crops as the Herrick. Crops grown on Piasa soils are affected by drought and by deficiencies in minerals to a greater degree than are those grown on the Herrick soils. INIinor acreages in this association are occupied by Har- ison, Virden, Cowden, Oconee, and Ebbert soils. The Har- ison andVirden soils are dark colored,^ and the other soils ai'e moderately dark colored. Natural drainage is poor or somewhat poor, but it has been improved by installing surface ditches and by instal- ling tile drains in places. In some areas, however, excess moisture remains a hazard to growing crops. The Piasa soils often remain wet in spring long after better drained soils are dry enough to be planted to crops. Very few tile drains have been installed in Piasa soils because water moves too slowly through the profile. Corn, soybeans, and wheat are the principal crops. Minor acreages are in alfalfa, red clover, and bluegrass pasture. 5. Cowden-Piasa Association Level, moderately dark colored soils that have a sloicly or venj slowly per-meahle suhsoil This soil association is mainly on broad flats in the cen- tral and southern parts of the county. It occupies about 14 percent of the total acreage in the county. Intermingled areas of Cowden and Piasa soils occupy about 50 percent of the association, and Cowden soils that are not intermingled with Piasa soils occupy about 20 per- cent. The Cowden soils are distinctly different from the Piasa soils in some ways, though they are intermingled with those soils. The main difference is that the Cowden soils have an acid subsoil, and the Piasa soils have an al- kaline subsoil that is high in content of exchangeable sodium. , Intermingled areas of Oconee and Tamalco soils, and Oconee soils that are not intermingled with Tamalco soils, occupy about 20 percent of the association. Virden and Eb- bert soils also occupy minor acreages. The Oconee and Tamalco soils are gently sloping, and the Virden and Eb- bert are mainly nearly level. In some places the Virden and Ebbert soils are in depressions. Wetness is a hazard, especially in spring. Because the subsoil is slowly or very slowly permeable, tile di'ains are rarely installed and surface ditches provide most of the supplemental drainage. Corn, soybeans, and wheat are grown on practically all of the acreage, though the soils are only moderately well suited to those crops. The soils are generally so wet that corn and soybeans cannot be planted before late in May or early in June, and the crops do not do so well as those planted earlier. 6. Cisne-Hoyleton-Huey Association Level to gently sloping, light-colored to moderately dark colored soils that have a sloioly permeahle or very shnvly ■permeahle suhsoil This soil association occupies only about 2 percent of the county and is mainly in the southeastern part. About 30 perceiit of it consists of intermingled areas of Cisne and Huey soils, about 25 percent consists of Cisne soils that are not intermingled with Huey soils, and another 25 percent consists of Hoyleton soils. The Cisne and Huey soils are nearly level, and the Hoyleton soils are gently sloping. The Cisne soils have a moderately dark colored surface layer, a grayish subsur- face layer, and a very slowly permeable subsoil. The Hoyleton soils are somewhat similar to the Cisne but are l)etter drained and have a more brownish profile. The Huey soils have a light-colored surface layer and lack the thick subsurface layer that is typical in the Cisne profile, or they have only a thin subsurface layer. Unlike the Cisne soils, they ha'\'e an alkaline subsoil that is high in content of exchangeable sodium. The Huey soils are poorly drained, but improvements in drainage are restricted to surface ditches because permeability is slow in the subsoil. A minor acreage in this association is occiipied by Ta- malco soils, which are gently sloping or sloping. These soils have a profile similar to that of the Hoyleton soils, but the lower part of their subsoil is alkaline and is high in exchangeable sodium. Douglas soils occupy a small acreage on high ridges, and Ebbert and Virden soils oc- cupy small areas in low spots. Also in small areas are Cowden and Piasa soils. The soils of this association are not so well suited to crops as are the nearly level soils in other parts of the county. jNIost of the aci*eage is in cash-grain farms, but there are a few general farms and dairy farms. Soybeans and wheat are the principal crops, but corn and alfalfa are o'rown to some extent. MONTGOMERY COUNTY, ILLINOIS 9 7. Oconee- Velma-Tamalco Association i\ early level to tit iv ugly sloping, moderately dark colored solU that have a slowly permeable, moderately permeable, or very slowly permeable subsoil This soil association occupies part of tlie rolling glacial drift plain in the central part of the county and is also in areas where streams are slightly entrenched in the glacial till plain. It occupies about 8 percent of the county. Oconee soils occupy about 50 percent of the association; Vehna soils, about '10 percent; and Tanialco soils, another 20 percent. The Oconee and Tanialco soils, which devel- oped in loess, are nearly level or gently sloping. The Vehna soils, which developed primarily in glacial drift, have stronger slopes. They occur in areas adjacent to streams. The Oconee soils have a moderately dark colored surface layer and a grayish-brown subsurface layer. Their subsoil is mottled grayish or brownish silty clay loam to silty clay. Tlie Vehna soils that are not eroded have a dark-colored surface layer. Their subsoil is brown clay loam. Tamalco soils have a surface layer that is similar to that of the Oco- nee soils, but they have only a thin, or practically no, subsurface layer. The upper part of the Tamalco subsoil is brown or reddish brown, and the lower part is gray mottled with brown. The lower part is alkaline and is high in ex- changeable sodium. Small acreages in this association are occupied by Cowden and Piasa soils. Another minor acreage is occupied by Douglas soils. Cash-grain farms, general farms, and dairy farms are predominant in this association. The principal crops are corn, soybeans, wheat, and alfalfa, but some of the more rolling areas are used for pasture. Erosion is a serious hazard in most places. If further erosion takes place, the consequences would be serious because the plow layer would then consist of material from the subsoil, and the subsoil is not suitable for crops. Water generally does not stand on these soils, but tillage is delayed after heavy rains because the soils dry slowly. Figure 4. — Principal soils of association 8 and their relationship to one another. 10 SOIL SURVEY 8. Hickory-Hosmer Association Gently sloping to very stecj), light-colored, moderately well drained and well drained soils on uplands adjacent to streams Tliis soil association is mainly on nplands adjacent to the larg-er creeks in the central and southern parts of the county. It occupies about 26 percent of the county and consists primarily of narrow ridges occupied by Hosmer soils, and of steeper Hickory soils on the side slopes (fig. 4) . Hickory soils occupy about ?>0 percent of the association, and Hosmer soils, about 20 percent. The Hickory soils liave developed in glacial till and are well drained. They generally have a surface layer of light-colored loam and a subsoil of brownish clay loam. The Hosmer soils have developed in loess and are moderately well drained. They have a surface layer of light-colored silt loam, underlain ])y a brownish subsoil. The lower part of the subsoil is mottled and contains a fragipan. Stoy soils occupy about 1.5 percent of this association, and Weir, Negley, Pike, Hennepin, and Lawson soils to- gether occupy about 35 percent. The Stoy soils are nearly level and are somewhat poorly drained. The Weir soils, on broad flats, are poorly drained. They have a grayish surface layer and a mottled, very slowly permeable subsoil. The Negley soils are steep and are on valley walls in areas of gravelly drift. The Pike soils lie above the Negley soils and in other rolling areas, and the Hennepin soils occur mainly on the lower parts of steep sloj^es. Lawson soils occur in many valleys of small streams. General farming is predominant in this association. Throughout much of the acreage, the soils are so sloping and siisceptible to erosion that they are not suitable for general farm crops and are used for pasture, as woodland, or as recreational areas (fig. 5). The soils are less suitable for crops than the soils of other associations, are less inten- si\-ely farmed, and generally produce a lower average per acre income. Also, the farms and fields ai'e normally smaller. The principal crops are corn, soybeans, wlieat, and clover. Many areas of this soil association have potential for use for parks, hunting preserves, or camping areas, and Figure J. — Typical area of association 8. Some parts of this association are suitable for parks and other recreational uses. as sites for other kinds of recreation. Many good sites are available for developing into artificial lakes. 9. Lawson-Radford Association Lerel, dark-colored, same what poorly drained soils on food plains This soil association consists of soils on flood plains of the larger streams. It occupies about 7 percent of the county. Lawson soils make up about 75 percent of the association, and Radford soils, about 10 percent. The Lawson soils are dark colored and are medium textured throughout. They are somewhat poorly drained and are subject to flooding but are suited to the crops commonly grown in the county, especially corn. The Radford soils 'consist of moderately dark colored, silty, recent sediinent over a layer of dark- colored silty clay loam. Starks, Camden, Terril, Nokomis, Landes, Racoon, and Colo soils occupy about 10 percent of this association. The Starks, Camden, Nokomis, and Terril soils are not subject to flooding. Tliey are mainly on terraces or on alluvial fans, mostly in areas where the smaller streams enter tlie valleys of larger streams. The Starks and Camden soils have developed in older alluvium than the soils on flood plains, and they have a finer textured and better defined subsoil. The Starks soils are somewhat poorly drained, and the Camden soils are well drained. The Nokomis soils are darker and have been weathered \ to a greater extent than the Lawson soils and are more acid than tliose soils. They are similar to the Terril and , Racoon soils but are not well drained like the Terril soils. < They are darker colored and better drained than the ' Racoon soils. Most of this association is used to grow corn and soy- beans. Winter wheat and clover are grown on some of the higher areas but are not grown extensively on tlie low areas, because of tlie hazard of flooding. The soils of flood plains are generally part of a farm that also contains the J soils of the adjacent uplands. Where the soils ai'e pro- tected from flooding, additional drainage can be provided by installing tile drains. If the soils have been protected ' from flooding and have had tile drains installed, they are among the best soils for crops in this county. Descriptions of the Soils This section describes the soil series and majiping units of Montgomery Comity. The acreage and pi-oportionate extent of each ma[>ping unit are given in table 4. The procedure is first to describe the soil series, and then the mapping units in that series. Thus, to get full in- formation on any one mapping unit, it is necessary to read the description of tliat unit and also the description of the soil series to which it belongs. As mentioned in the section 'TTow This Survey Was Made," not all mapping units are members of a soil series. Gullied land, for exaniple, is a miscellaneous land type that doos not belong to a soil series. It is listed, nevertheless, in al|)habetic order along v.ith the soil series. In comparing a mapping unit Avith a soil series, many will prefer to read the short description in paragraph form. It precedes the technical description that identifies layers by A, B, and C horizons and depth ranges. The technical profile descrii)tions ai'e mainly for soil scientists and others MONTGOMERY COUNTY, ILLINOIS Table 4. — Approximate acreage and proportionate extent of the soils 11 Soil Area Blair silt loam, 5 to 9 percent slopes, eroded Blair soils, 5 to 9 percent slopes, severely eroded Camden silt loam, 2 to 4 percent slopes Camden silt loam, 4 to 7 percent slopes, eroded Chauncey silt loam Cisne silt loam Cisne-Huey complex Clarksdale silt loam Colo silty clay loam Cowden silt loam Cowden-Piasa complex, to 2 percent slopes... Cowden-Piasa complex, 2 to 4 percent slopes, eroded Douglas silt loam, 2 to 4 percent slopes Douglas silt loam, 4 to 7 percent slopes Douglas silt loam, 4 to 7 percent slopes, eroded Douglas silt loam, 7 to 12 percent slopes Ebbert silt loam Gullied land Harrison silt loam, to 2 percent slopes Harrison silt loam, 2 to 4 percent slopes Harrison silt loam, 2 to 4 percent sloi^es, eroded H;irrison silt loam, 4 to 7 percent slopes Harrison silt loam, 4 to 7 percent slopes, eroded. Harvel silty clay loam Herrick silt loam Herrick-Piasa complex Hickory loam, 7 to 12 percent slopes Hickory loam, 7 to 12 percent slopes, eroded Hickory soils, 7 to 12 percent slopes, severely eroded Hickory loam, 12 to 18 percent slopes Hickory loam, 12 to 18 percent slopes, eroded Hickory soils, 12 to 25 percent slopes, severely eroded Hickory loam, 18 to 30 percent slopes Hickory loam, 30 to 60 percent slopes Hickory-Hennepin loams, 18 to 30 percent slopes Hickory-Hennepin loams, 30 to 60 percent slopes Hickory and Negley loams, 15 to 35 percent slopes Hosmer silt loam, 2 to 4 percent slopes Hosmer silt loam, 4 to 7 percent slopes Hosmer silt loam, 4 to 7 percent slopes, eroded „ . Hosmer soils, 4 to 7 percent slopes, severely eroded Hosmer silt loam, 7 to 12 percent slopes, eroded. Hosmer soils, 7 to 12 percent slopes, severely eroded Hoyleton silt loam, to 2 percent slopes Hoyleton silt loam, 2 to 5 percent slopes Hoyleton silt loam, 2 to 5 percent slopes, eroded. Acres 2, 526 511 249 417 1, 794 2,610 2, 992 1, 410 269 14, 149 31, 337 954 837 1, 310 581 389 6, 542 107 973 12, 645 542 681 881 1,315 51, 830 50, 012 1, 153 3,971 1, 199 2, 691 4,275 1, 741 15, 202 2, 726 5,433 1,707 1, 037 11, 134 2,662 5, 005 674 1, 743 480 1,577 2, 984 390 Extent Percent 0. (') ■ (') (') 3. 1 6.9 .2 .2 .3 . 1 1.4 (■) . 2 2.' 8 . 1 . 1 .2 .3 11.5 11. 1 .3 .9 .3 .6 .9 .4 3.4 1.2 .4 .2 2.5 .6 1. 1 . 1 .4 . 1 .4 . 7 (') Soil Area Extent Hoyleton-Tamalco complex, 1 to 4 percent slopes Ipava silt loam Landes fine sandy loam Lawson silt loam Nokomis silt loam Oconee silt loam, to 2 percent slopes Oconee silt loam, 2 to 4 percent slopes Oconee silt loam, 2 to 4 percent slopes, eroded. _ Oconee silt loam, 4 to 7 percent slopes Oconee silt loam, 4 to 7 percent slopes, eroded.. Oconee-Tamalco complex, to 2 percent slopes. Oconee-Tamalco complex, 2 to 4 percent slopes. Oconee-Tamalco complex, 2 to 4 percent slopes, eroded Oconee-Tamalco complex, 4 to 7 percent slopes, eroded O' Fallon silt loam, 2 to 4 percent slopes Pana loam, 4 to 7 percent slopes, eroded Pana loam, 7 to 14 percent slopes, eroded Pike silt loam, to 2 percent slopes Pike silt loam, 2 to 4 percent slopes Pike silt loam, 4 to 7 percent slopes Pike silt loam, 4 to 7 percent slopes, eroded Pike silt loam, 7 to 12 percent slopes, eroded Racoon silt loam lladf ord silt loam Shiloh silty clay loam Shiloh silt loam, overwash Sicily silt loam, 2 to 4 percent slopes Sicily silt loam, 4 to 7 percent slopes, eroded Starks silt loam Stoy silt loam, to 2 percent slopes Stoy silt loam, 2 to 4 percent slopes Tamalco silt loam, 2 to 4 percent slopes Tamalco silt loam, 2 to 4 percent slopes, eroded. Tamalco silt loam, 4 to 7 percent slopes, eroded. Terril loam, 2 to 5 percent slopes Velma loam, 4 to 7 percent slopes Velma loam, 4 to 7 percent slopes, eroded Velma loam, 7 to 12 percent slopes Velma loam, 7 to 12 percent slopes, eroded X'elma loam, 12 to 18 percent slopes X'elma-Walshville complex, 4 to 7 percent slopes, eroded ^'elma-Walshville complex, 7 to 12 percent slopes, eroded ^"irden silty clay loam Weir silt loam Water Quarry, gravel pits, borrow pits, mine dumps, and made land Total Acres Percent 703 0. 1 1, 249 .3 114 (') 24, 330 5.4 595 . 1 9, 071 2.0 21, 791 4.8 2, 177 . 5 2, 017 .4 5, 528 1.2 3,593 . 8 12, 976 2.9 3, 551 .8 2,634 . 493 . 1 212 (■) 386 (') 147 (') 1, 640 .4 1,050 ■> 934 ■) 837 9 537 . 1 2, 634 .6 778 .2 222 (') 2, 594 .6 915 . 2 558 . 1 7, 282 1.6 11, 145 2.5 4, 166 .9 1,387 .3 472 . 1 445 (') 1, 099 .2 4, 151 .9 1, 040 .2 2, 069 . 5 715 .2 1,903 .4 731 .2 51, 988 11.5 2, 531 .6 311 (■) 492 . 1 451, 840 100.0 ' Less than 0.1 percent. who want detailed information about soils. Unless other- wise indicated, the colors given in the descriptions are those of a moist soil. Some of the terms used to describe the soils are defined in the Glossary at the back of this soil sui-vey. Following the name of each mapping unit, there is a symbol in parentheses. This symbol identities the mapping unit on the detailed soil map. Listed at the end of each de- scription of a mapping unit are the management group and woodland group in which the mapping unit has been placed. The pages on which each management group and woodland group are described can be found by referring to the "Guide to JNIapping Units" at the back of this survey. Blair Series Deep, light-colored, sloping to rolling soils Huit de- veloped in glacial till in the forested areas of the county are in the Blair series. These soils are in the upper parts of the valleys of small streams in the uplands. They re- ceive extra water that seeps from higher areas of adjacent soils and are often slow to dry out after rainy periods. In most places the surface layer is about 7 inches thick. It consists of dark grayish-brown silt loam that has grantdar structure and is strongly acid to medium acid. The subsoil, about 30 inches thick, is mainly grayish-brown 12 SOIL SURVEY hea^^" clay loam or silty clay loam that is mottled with yellowish brown, has subangular blocky structure, and is very strongly acid or strongly acid. The underlying ma- terial is gray clay loam mottled with strong brown. It is massive and is slightly acid to neutral in i-eaction. Blair soils have moderately slow or slow permeability and moderate to high available moisture capacity. They are low in content of organic matter, nitrogen, jjhosphoi'us, and potassium. Except in areas where lime has been added, the surface layer is strongly acid. All of these soils are eroded, and further ei'osion is a serious hazard. Representative profile of a Blair silt loam (300 feet nortli and 50 feet west of the center of sec. 2, T. 7 N., K. 4W.): AiJ — to 7 inches, dark graytsli-browu (lOYR 4/2) silt loam ; weak, fine, granular structure ; friable when moist, sticky and plastic \Yhen wet ; strongly acid to medium acid ; abrupt, smooth boundary. Bl — 7 to 9 inches, brown (lOYR 5/3) gritty light silty clay loam; common, fine, distinct, dark-brown to brown (7..5YR 4/4) mottles; moderate, fine, subangular blocky structure ; firm when moist, sticky and plastic when wet ; very strongly acid ; clear, smooth boundary. B21t— 9 to 13 inches, grayish-brown (10 YR 5/2) heavy clay loam; few, fine, distinct, dark yellowish-brown (lOYR 4/4) mottles; strong, fine, subangular blocky struc- ture ; when dry, most peds coated with light-gray (lOYR 7/1) silt grains; firm when moist, sticky and very plastic when wet; very strongly acid; clear, smooth boundary. B22t— 13 to 28 inches, grayish-brown (2.5Y 5/2) gritty silty clay loam; few, fine, distinct, dark yellowish-brown (lOYR 4/4) mottles; strong, medium, blocky struc- ture; has continuous dark grayish-brown (lOYR 4/2) clay films on the larger peds and grayish-brown (lOYR 5/2) clay films on the smaller peds; firm when moist, sticky and very plastic when wet ; very strongly acid ; gradual, smooth boundary. B3t — 28 to 37 inches, gray (lOYR 5/1) heavy clay loam; many, fine to coarse, prominent, yellowish-brown (lOYR .5/4) to strong-brown (7..5YR .5/8) mottles; weak, coarse, blocky structure; firm when moist, sticky and very plastic wlien wet ; contains some large areas of iron and manganese accumulation that have a black (5YR 2/1) center surrounded by yellowish-red (5YR 4/8) and strong-brown (7. SYR 5/8) material ; strongly acid ; gradual, smooth boundary. C — 37 to 110 inches, mixed gray (lOYR 5/1) and strong-brown (7. SYR 5/8) clay loam; few, fine, prominent, black (lOYR 2/1) mottles ; massive; firm when moist, sticky and plastic when wet; slightly acid to neutral in re- action. On the upper parts of the slopes, where the Blair soils grade to Stoy soils and other soils developed in loess, some loess is mixed with the weathered till in the A horizon. The surface layer of a typical Blair soil contains enough sand to give it a gritty feel. Blair soils occur with Hickory, Hosmer, and Stoy soils. They have a grayish-brown subsoil, rather than a brown subsoil like the Hickory soils. Unlike the Hosmer and Stoy soils, they have gritty and gravelly material in all horizons. Blair silt loam, 5 to 9 percent slopes, eroded (5C2). — This soil has the profile described as representative for the series. Included in mapping, however, were small areas in which the present plow layer consists of material from the subsoil. Also included were some areas in which tlie surface layer is thicker than the one in the profile described, and other small areas in which the profile is similar to that of the Walshville soils. The included soils are of too limited extent and occur in too irregular a pattern to be shown sep- arately on the soil map. They are not so well suited to crops as the typical Blair soil and are more difficult to manage. Unless terraces are installed and tillage is done on the contour to reduce losses from erosion, this Blair soil is better suited to hay crops and pasture than to cultivated crops. Even where terracing and contour tillage are prac- ticed, a cropping system in which grasses and legumes are grown at least half the time is needed to help control erosion. Crop residue, left on the surface, also provides pro- tection. If this soil is well managed and is fertilized, it is moderately well suited to corn, soybeans, and wheat. (Man- agement group IIIe-1, Avoodland group .3) Blair soils, 5 to 9 percent slopes, severely eroded (5C3). — The plow layer of this soil consists mainly of brown material from the subsoil. It has a texture of silty clay loam to silt loam and is sticky and plastic when Avet. The plow layer is lower in content of organic matter, is in poorer tilth, and is harder to till than the original one. Just be- neath it is a layer of heavy clay loam. Losses of soil ma- terial from the surface layer, and the unfavorable charac- teristics of the present plow layer, have caused the amount of runoft' to be greater than on Blair soils that are less eroded. These soils are poorly suited or only moderately well suited to the crojDS commonly grown in the county. They are suited mainly to pasture and hay but can be used oc- casionally for a row crop if terraces are constructed to help control erosion. (INIanagement group IVe-1, woodland group 3) Camden Series The soils of the Camden series are well drained, light colored, and gently sloping or sloping. They have devel- oped in silty or loamy alluvial material on stream terraces and alluvial fans in the valleys of the larger streams. The original cover was a forest of hardwoods, but practically all of the acreage has now been cleared and planted to ' crops. In most i:)laces the surface layer is about 8 inches thick. •! It consists of brown to dark-brown silt loam that has gran- ular structure and is medium acid. The subsoil, about 32 inches thick, consists of l)rown to dark-brown silty clay loam that is medium acid to strongly acid. The underlying material is brown, stratified silt loam to loam or clay loam and is medium acid. Camden soils have high available moisture capacity and moderate permeability. They are generally strongly acid, except in areas where the i)low layer has received lime. The content of organic matter, nitrogen, and phosphorus is low, and the content of potassium is medium. Erosion is a hazard if row crops are gTown, unless practices are used that protect these soils. At times, some small areas are flooded for short periods when the level of a stream is high. Representative profile of a C'amden silt loam (452 feet east and 168 feet north of the center of sec. 22, T. 8 X., R. 4 W.) : Ai5 — to 8 inches, brown to dark-brown (lOYR 4/3) silt loam; moderate, fine, granular structure; friable; medium acid : abrupt, smooth boundary. Bl — 8 to 11 inches, brown to dark-brown (7.5YR 4/4) light silty clay loam ; strong, fine, subangular blocky structure ; friable ; medium acid ; clear, smooth boundary. B21— 11 to 20 inches, brown to dark-brown (7.5YR 4/4) silty clay loam ; strong, fine and medium, subangular to an- MONTGOMERY COUNTY, ILLINOIS 13 gular blocky structure ; firm ; thin clay films on the structural aggregates; strongly acid; gradual, smooth boundary. B22— 20 to 29 inches, brown to dark-brown (7.5YR 4/4) silty clay loam; moderate, medium, subangular blocky structure ; firm : thin clay films on the structural ag- gregates ; medium acid ; gradual, smooth l)oundary. B3— 29 to 40 inches, brown (7.5YR 5/4) light gritty silty clay loam ; weak, coarse, subangular blocky structui-e ; fri- able to firm; thin clay films on the structural aggre- gates; medium acid: gradual, smooth boundary. C — iO to 00 inches, brown (7..')YR 5/4) silt loam, loam, and clay loam in poorly defined strata ; friable to firm ; medium acid. In some parts of the county, the profile of these soils contains more sand than the profile described as typical. Also, the A horizon is several inches thicker in some areas. Camden soils occur with Starks soils but are better drained than those soils. Camden silt loam, 2 to 4 percent slopes (134B). — This soil has the prohle described for the series. It receives runoff carried by small streams from the adjacent up- lands, in addition to receiving- the normal amount of rain- fall. This increased volume of water causes a serious haz- ard of erosion. If tillage is on the contour, row crops can be grown 2 years out of 3. Where terraces have been installexl, row crops can be grown 3 years out of 4. Adequate fertilization is needed, and well-i)laced diversion terraces can be used to help control runoff. (^lanagement group Ile^l, wood- land group 1 ) Camden silt loam, 4 to 7 percent slopes, eroded (134C2). — This soil has a dark yellowish-brown surface layer that is thinner than the one in the profile described for the series. In places the surface layer contains some material from the upper part of the subsoil. In a few other places, all of the plow layer consists of soil material from the upper part of the subsoil. Included in mapping were a few small areas tliat have short slopes of more than 7 percent. Practices are needed that help to protect this Camden soil from erosion. Even where terraces have been installed and contour tillage is jiracticed, a cropping system in wliich meadow crops are grown at least one-fourth of the time is necessary. Adequate fertilization is also needed. (Management group IIe-2, woodland group 1) Chauncey Series In the Chauncey series are moderately dark colored, poorly drained soils that are gently sloping. These soils have developed in loess, under the influence oJf prairie vege- tation. They are generally at the base of rounded morainal knolls in the eastern part of the comity. In most places the surface layer is about 11 inches thick and consists of very dark grayish-brown to very dark gray silt loam that has granular structure. It is slightly acid to neutral in reaction. The subsurface layer, about 25 inches thick, is dark colored (dark gray) in the upper part and light brownish gray in the lower part. It consists of silt loam that has platy structure and is very strongly acid. The sul)soil is about 24 inches thick. It is dark-gray to grayish-brown silty clay loam mottled with dark yellow- ish brown. The subsoil has blocky structure and is strongly acid to slightly acid in reaction. The underlying material is grayish-brown silty clay loam that is massive and is slightly acid to neutral in reaction. Chauncey soils have slow permeability and slow internal drainage. They receive runoff' from adjacent higher lying- soils. Water tends to accmiuilate on the surface, and as a result these soils are wet in spring. The available mois- ture capacity is high. Except in the lower part of the sub- soil, where these soils are slightly acid, they are strongly acid. They are low in content of available phosphorus and potassium and are medium in content of organic matter and nitrogen. Representative profile of Chauncey silt loam (465 feet north and 78 feet east of the SE. corner of NW40, NE160, sec.l4,T.8N.,R.2W.): Ai) — to 7 inches, very dark grayish-brown (lOYR 3/2) silt loam ; weak to moderate, fine, granular structure ; friable ; slightly acid to neutral ; abrupt, smooth boiuulary. Al — 7 to 11 inches, very dark gray (lOYR 3/1) silt loam; weak, medium and fine, granular structure ; friable ; medium acid ; clear, smooth boundary. A21 — 11 to 22 inches, dark-gray (lOYR 4/1) silt loam; some gray (lOYR 5/1) mottles and common, fine, faint, very dark grayish-brown (lOYR 3/2) mottles; weak, thin, platy structure ; friable ; very strongly acid ; clear, smooth boundary. A22— 22 to 30 inches, light brownish-gray (lOYR 0/2) silt loam ; common, medium, distinct, very darlc grayish- brown (lOYR 3/2) mottles; moderate, thin, platy structure; a few dark-gray (lOYR 4/1) coatings of organic matter on the structural aggregates; friable; niunerous iron concretious ; very strongly acid ; abrupt, smooth boundary. B21t— 30 to 40 inches, grayish-brown (lOYR 5/2) heavy silty clay loam ; common, medium, distinct, dark yellowish- brown (lOYR 3/4) mottles; weak, coarse, prismatic structure breaking to moderate, medium, angular blocky structure ; firm ; sti'ongly acid ; clear, smooth boundary. B22t— 40 to 54 inches, dark-gray (lOYR 4/1) heavy silty clay loam ; common, medium, distinct, dark yellowish- brown (lOYR 3/4) mottles; weak, coarse, prismatic structure breaking to moderate, medium, angular blocky structure; thick, vei-y dark gray (lOYR 3/1) clay films on the structural aggregates ; firm ; medium acid ; clear, smooth boundary. B3t — .54 to 00 inches, gray ( lOYR 5/1) silty clay loam; many, medium, distinct, d;irk yellowish-brown (lOYR 4/4) mottles; weak, coarse, prismatic .structiire breaking to weak, coarse and medium, angular blocky struc- ture; dark -gray (lOYR 4/1) clay films on the struc- tural aggregates ; firm ; slightly acid ; clear, smooth boundary. C — 00 to 00 inches, grayish-brown (2.5Y 5/2) silty clay loam; many, medium, prominent, yellowish-brown (lOYR 5/8) mottles; massive; firm; few very dark gray (lOYR 3/1) clay films along cleavage planes; slightly acid to neutral. The total thickness of the A horizons ranges from 24 inches to 40 inches. Texture of the B horizons ranges to light silty clay in some places. Chaunce.v soils occur with Cowden soils. Their profile is similar to that of the Cowden soils, but their A2 horizon is thicker. Chauncey silt loam (1 to 3 percent slopes) (287). — This is the only Chauncey soil mapped in Montgomery County. Its profile is the one described for the series. The dominant slope is nearly 3 percent. This soil occurs at the base of knolls and ridges. In places it receives soil material from moderately sloping, higher lying soils, and that material is gradually deposited on the surface. Included in mapping were a few areas covered by recent deposits of silt loam washed from the adjacent higher lying soils. 14 SOIL SURVEY Contour tillage and terracino- are needed to help control erosion. Where contour tillage is practiced and the soils are terraced, a cro]>ping system in which meadow crops are grown one-fourth of the time adequately controls erosion. If these practices are not used, growing meadow crops about half of the time keeps losses from erosion low. This soil is suited to the row crops commonly grown in the county, and it is used mainly for those crops. Fertilizer is needed. (Management group IIIw-1, woodland group 7) Cisne Series Soils of the Cisne series are deep, moderately dark col- ored, and poorly drained. They are nearly level and occur on uplands in the southern part of the county. These soils have developed under the influence of prairie vegetation in loess that is underlain by till of Illinoian age. The subsoil is dense and compact and is commonly called a claypan. Tlie surface layer is generally about 11 inches thick and consists of very dark grayish-brown silt loam that has granular structure and is medium acid. The subsurface layer, which also has a texture of silt loam, is about 10 inches thick. It is grayish brown in the upper part and light gray in the lower part, has granular structure or is massive, and is strongly acid to medium acid. The subsoil, to a depth of about 60 inches, consists of dark grayish- brown to gray silty clay loam mottled with dark yellowish brown and yellowisli brown. It has blocky structure and is medium acid to neutral in reaction. Cisne soils have slow or very slow permeability and higli available moistvire capacity. They are moderate to low in content of organic matter, nitrogen, phosphorus, and po- tassium. Except in areas where lime has been added, the surface layer is medium acid to strongly acid. Representative profile of a Cisne silt loam (48 feet north and 2-1: feet east of the SW. corner of NAV40, NW160, sec. 16,T.7N.,R.2W.): Al— to 11 inches, very dark grayi.sli-brown (lOYR 3/2) silt loam; moderate, fine, granular structure: friable when moist, slightly sticky and slightly plastic when wet ; medium acid; gradual, smooth boundary. A21^11 to IS inches, grayish-brown (lOYK ~>/-l) silt loam; weak, fine, granular structure: friable when moist, slightly sticky and slightly plastic when wet ; strongly acid to medium acid; clear, smooth boundary. A22— 18 to 21 inches, light-gray ( lOYR 6/1) silt loam; few, fine, prominent, dark yellowish-brown (lOYR 4/4) mottles; massive; friable when moist, not sticky and not plastic when wet ; strongly acid to medium acid ; abrupt, smooth boundary. B21t— 21 to 28 inches, dark grayish-brown (lOYR 4/2) silty clay loam to silty clay ; many, fine distinct, dark yel- lowish-brown (lOYR 4/4) mottles; weak to moderate, medium and fine, angidar blocky structure: dark-gray ( lOYR 4/1 ) clay films ; firm when moist, very plastic and very sticky when wet ; medium acid ; gradual, smooth boundary. B22t— 28 to 40 inches, gray (lOYR 5/1) silty clay loam; few, fine, prominent, yellowi.sh-brown (lOYR .5/8) mottles; weak to moderate, coarse, angular blocky structure; very plastic when wet; neutral in reaction; gradual, smooth boundary. B3 — 40 to (K) inches, same as the B22t horizon, except that the texture is light silty clay loam. In many places the B horizons are more acid than those in the profile described as typical for the series. Cisne soils occur witli Hoyleton and Douglas soils (fig. 6) but are less brownish in the upper part of the subsoil than the Hoyleton soils. They also occur with Huey soils. In areas of Cisne soils adjacent to Huey soils, the reaction in the lower part of the subsoil ranges to neutral. The Cisne soils have colors about intermediate between those of the moderately dark colored Cowden soils and the light-colored Weir soils. Cisne silt loam (0 to 1 percent slopes) (2). — This soil has the profile described, as typical for the Cistie series. It is low in natural fertility but is well suited to corn, soy- beaais, wheat, and clover if it is properly fertilized. In most years it is too wet for tillage early in spring. Con.se- quently, crops are f requetitly planted too late to grow well. (Matiagetneftt group IIIw-1, woodland group 7) Cisne-Huey complex (0 to 1 percent slopes) (991). — This soil complex consists of a moderately dark colored Cisne soil and a light-colored Huey soil. The soils are poorly drained and are nearly level. They are intermingled in such an intricate pattern that it was not practical to separate them on the soil map. The proportiotis of each soil vary from place to place. Most areas contain about equal paries of Ci.sne and Huey soils, but the Cisne soil is most extensive in a few places. The soils occur with soils of the Hoyleton- Tamalco complex in the soutliern ])art of the county. They reseml)le the soils of the Cowdeti-Piasa and Herrick-Piasa complexes, except that they have a lighter colored surface layer. The profile of the Cisne soil is similar to the one descril)ed for the Cisne series. A profile similar to that of the Huey soil is described imder the Huey series. Where the soils of this complex have been plowed, the pattern in which they occur can be easily seen after a heavy rain. The Iltiey soil is readily distinguished by its light- colored surface layer. Also, it has less favorable structure than the Cisne soil, and this structure easily breaks down and allows the surface soil to run together. Tlien, the sur- face becomes smooth and compact though the adjacent Cisne soil retains its cloddy form and rough surface. The Huey soil has a thiimer surface layer than the Cistie soil. In places the surface layer of the Pluey soil is so thifi that a thin slice of the subsoil is deposited on the surface dtiring tillage. A soil that has such a thin sttrface layer is poorly suited to crops. The Cisne and Huey soils have slow or very slow permea- bility. The Cisne soil is medium acid to strongly acid and is low in exchangeable sodium. The Huey soil has a subsoil that is moderately alkalitie and is high in exchangeable sodium. Both of these soils have a low content of orgaitic matter, nitrogen, phosphorus, and potassium. Additional improvements in drainage are needed, though surface ditches have already been itistalled in many places. The soils are suited to com, soybeans, wheat, and legume-grass mixtures if they are properly drained and fertilized. (Management group IVw-1, woodland group 7) Clarksdale Series Soils of the Clarksdale series are moderately dark col- ored, nearly level, and somewhat jjoorly drained. They are on uplands in the northern and central parts of the county, where they have developed in loess that is underlaiti by Illinoian till. The places in which these soils have formed were border areas where forests were encroaching on the original prairie. The original vegetation was a forest of hardwoods or forest vegetatioti mixed with grasses. MONTGOMERY COUNTY, ILLINOIS 15 Figure 6. — A field of Cisne, Hoyleton, and Douglas soils planted to corn. The Cisne and Hoyleton soils are in the foreground, and the Douglas soils are on the morainal knoll in the background. In most places the surface layer is about 7 inches thick. It consists of very dark g'ray to very dark orayish-hrown silt loam that has granular structure and is slightly acid to neutral in reaction. The subsurface layer, about 7 inches thick, consists of very dark gray to dark grayish-brown silt loam and generally has weak subangular blocky to platy structiu'e and is strongly acid. The subsoil is about 39 inches thick. The upper part of the subsoil is brown silty cla}' loam mottled with yellowish brown, and the lower part is olive-gray to gray silty clay loam, also mottled with yellowish brown. The stnicture of the subsoil is mostly blocky, and the reaction is strongly acid to neutral. The underlying material is nearly massive silty clay loam that is about neutral in reaction. Clarksdale soils are suited to corn, soybeans, wheat, and other crops commonly grown in the area. They have high available moisture capacity, have moderately slow perme- ability, and are fertile. Except in areas where the i>low layer has received lime, these soils are generally medium acid to strongly acid throughout the solum. Their content of organic matter, nitrogen, phosphorus, and potassium is medium. Representative profile of Clarksdale silt loam (618 feet south and 255 feet east of the NW. corner of the SW40 of the SW 160, sec. 25, T. 10 N., R. 5 W.) : Ap — to 7 inches, very dark gray (lOYR 8/1) to very dark grayi^ih-brown (lOYR S/2) silt loam; weak, mediiiiu. granular structure; friable; slightly acid to neutral; abrui>t, smooth boundary. A21— 7 to 12 inches, very dark gray (lOYR 3/1) to dark gray (lOYR 4/1) silt loam; weak, fine, subangular bloc-ky structure ; friable ; strongly acid ; clear, smooth bounda ry. A22— 12 to 14 inches, dark-gray ( lOYR 4/1) to dark grayish- brown (lOYR 4/2) silt loam; weak, thick, platy struc- ture and weak, very fine, subangular blocky structure ; friable; strongly acid; abrupt, smooth boundary. A2&Bt— 14 to 10 inches, brown (lOYR .^/S) silty clay loam; few. fine, faint, yellowish-brown (lOYR 5/S) mottles; strong, medium and fine, subangular bhx-ky structure; few dark grayi.sh-brown ( lOYR 4/2) clay films; thick gray silt coatings on the structural aggregates ; firm : strongly acid; abrupt, smooth lioundar.v. B21t — 1(J to 21 inches, brown ( lOYR .5/3) heavy silty clay loam; common, faint, yellowish-brown (lOYR 5/8) mottles ; moderate, fine and medium, prismatic struc- ture breaking to .strong, medium and fine, blocky structure; dark-gray (lOYR 4/1) to dark grayish- brown ( lOYR 4/2 ) clay films ; firm ; strongly acid ; clear, smooth bounda r.v. B22t — 21 t(j 30 inches, olive-gra.v (HY "1/2 ) heavy silty clay loam; many, medium, prominent, yellowish-brown ( lOYR .5/4 to .5/8) mottles; strong, medium, pris- matic stnicture breaking to moderate blcK'ky struc- ture; dark-gray ( lOYR 4/1) to dark grayish-brown (lOYR 4/2) clay films; very firm; strongly acid; gradual, smooth boundary. 16 SOIL SURVEY B31t — 36 to 44 inches, gray (5Y 5/1) silty clay loam in upper part and silt loam in lower part : many, prominent, yellowisli-brown (lOYR .5/4 to 5/8) mottles: moder- ate, coarse, prismatic structure breaking to weak, coarse, angular blocky structure ; very dark gray (lOYR 3/1) and black (lOYR 2/1) clay films; very firm ; slightly acid ; clear, smooth boundary. B32 — 44 to 55 inches, gray (5Y 5/1) gritty heavy silt loam; many, coarse, prominent, dark-brown to brown (7.5YR 4/4) mottles and common, coarse, distinct, dark yel- lowish-brown (lOYR 4/4) mottles; weak, coarse, pris- matic structure; Arm when moist: thick, black (lOYR 2/1) and dark-gray (lOYR 3/1) clay films; neutral; clear, smooth boundary. C — 55 to 65 inches, gray (lOYR 5/1) light clay loam contain- ing some pebbles ; many, coarse, distinct, dark yellow- ish-brown (lOYR 4/4) mottles; weak, coarse, pris- matic structure; firm; thick, black (lOYR 2/1) and very dark gray (lOYR 3/1) clay films in the cleavage planes; neutral. The boundary between the A and B horizons is less abrupt in many places than indicated in the profile described as typi- cal. In some places the B hoi'izons are more brownish than those in the profile described. Depth to the underlying Illinoian till ranges from .50 to 70 inches. Tlie Clarksdale soils in this county are slightly better drained than typical for this series. Because the Clark.sdale soils originated in border areas where forest was encroaching on the original prairie, they have characteristics intermediate between those of the Herrick soils, developed under prairie, and the Stoy soils, develoi>ed under forest. The Clarksdale soils are lighter colored than the Herrick soils and darker colored than the Stoy. Clarksdale silt loam (0 to 2 percent slopes) (257). — This is the only Clarksdale soil mapped in this county. Its pro- file is like the one described for the series, except that in many places the boundary between the subsurface layer and the subsoil is more gradual. Included in mapping were areas in Avhich the reaction in the loAver part of the subsoil is alkaline. Clarksdale silt loam is well suited to corn, soybeans, wheat, and other crops commonly grown in the county. It is used mainly for those crops, but proper fertilization is required if satisfactory returns are to be maintained. Tile drains are also needed in places, though they have already been installed in some areas. A good seedl)ed is obtained, whether plowing is done in spring or in fall. (Manage- ment group 1-2, woodland group 3) Colo Series In the Colo series are deep, dark-colored, nearly level soils that are poorly drained. These soils have developed in alluvial material that has a texture of silty clay loam. They occur in some of the low areas in the valleys of major streams throughout the county. The Colo soils Avere orig- inally covered with mixed vegetation consisting of grasses and forest plants. In most places the surface layer, to a depth of about 9 inches, is very dark grayish-brown silty clay loam that has granular structure and is mildly alkaline. Beneath this is very dark gray or black silty clay loam that extends to a depth of about 58 inches. The underlying material is dark-gray silty clay loam. Colo soils are moderately permeable and have very high available moisture capacity. They are high in content of organic matter, nitrogen, phosphorvis, and potassium and are neutral to alkaline in reaction. Flooding is a hazard. Therefore, these soils are better suited to corn, soybeans, and other crops that mature in fall than to wheat or other crops that are on the soil during winter. Representative profile of Colo silty clay loam (216 feet west and 312 feet south of the NE. corner of NE40, NW1(30, sec. 16, T. 7 N., R. 4 W. ) : All— to 9 inches, very dark grayish-brown (10 YR 3/2) silty clay loam ; moderate, medium, granular structure ; friable ; mildly alkaline ; clear, smooth boundary. A12— 9 to 23 inches, very dark gray (lOYR 3/1) silty clay loam ; moderate, medium, angular blocky structure ; firm ; neutral : gradual, smooth boundary. A13— 23 to 52 inches, black (lOYR 2/1) silty clay loam; mod- erate, medium, angular blocky structure ; firm ; neu- tral ; gradual, smooth boundary. A14— 52 to .58 inches, very dark gray (lOYR .3/1) silty clay loam ; firm ; neutral : gradual, smooth boundary. Cg— 58 to 64 inches, dark-gray (lOYR 4/1) silty clay loam; firm ; neutral. Colo soils occur with Lawson soils. They are finer textured than the Lawson soils, but their profile resembles that of the Lawson soils in other ways. Colo silty clay loam (0 to 2 percent slopes) (402). — This is the only Colo soil mapped in Montgomery County. Its profile is the one described as typical for the series. In many areas of this soil, improvement in drainage is needed. It can be provided by digging o})en ditches. Tile drains could also be installed if the hazard of flooding were eliminated. (Management group IIw-1, Avoodland group 7) Cowden Series In the Cowden series are deep, moderately dark colored soils that are poorly drained and nearly level. These soils develoi^ed in loess under prairie vegetation. They occur in the prairie areas of jNIontgomery County but especially in the southern and eastern parts. In most places the surface layer is about 8 inches thick and consists of very dark gray silt loam that has granular structure and is medium acid. The subsurface layer, about 9 inches thick, also has a texture of silt loam and is dark gray in the upper part and grayish brown to gray in the lower part. It has platy to subangular blocky structure and is strongly acid. The subsoil is about 38 inches thick and consists of grayish-brown, olive-gray, and light olive- brown silty clay loam to silty clay, with l)rownish or olive- gray mottles. It has blocky structure. Reaction is strongly acid in the upper part to neutral in the lower part. The subsoil is slowly permeable. Therefore, tile drains will not work well enough for installing them to be eco- nomically feasible. The available moisture capacity is high, and the content of organic matter, nitrogen, phos- phorus, and potassium is medium. Except in areas adja- cent to Piasa soils, the reaction is medium acid to very strongly acid. In some areas adjacent to Piasa soils, how- ever, the reaction in the lower part of the subsoil is neutral to alkaline. Representative profile of Cowden silt loam (438 feet south and 260 feet east of a point in the center of State Highway Xo. 185 and directly in front (south) of the center of a farmhouse located on the north side of State Highway No. 185 and in the NWIO of the SE40 of the NW160," sec. 28, T. 8 N., R. 3 W. ; laboratory data for this profile are given in Soil Survey' Investigations Report for Illinois).* * United States Department op Agriculture, soil surx'ey lab- oratory DATA AND DESCRIPTIONS OF SOME SOILS OF ILLINOIS. Soil Sur- vey Invest. Rpt. Soil Conservation Service in coop, with 111. Agr. Expt. Sta. [Unpublished manuscript] MONTGOMERY COUNTY, ILLINOIS 17 Ap — to 8 inches, very dark gray (10 YR 3/1) silt loam ; weak, coarse, srauular structure; friable; medium acid; abrui)t, smooth boundary. A21 — S to 14 inches, dark gray (lOYR 4/1) to very dark gray (lOYR 3/1) silt loam; many, faint, grayish-brown (lOYR 5/2) mottles; moderate to strong, medium, platy structure ; friable ; common, fine pores ; many fine iron concretions ; strongly acid ; clear, smooth boundary. A22— 14 to 17 inches, grayish-brown (lOYR 5/2) to gray ( lOYR 5/1) silt loam; common, faint, dark-gray (lOYR 4/1) and light-gray to gray (lOYR 6/1) mottles; weak, medium, plat.y structure breaking to moderate, very fine, subangular block.y structure; friable; very por- ous, and pores are fine and tubular ; strongly acid ; clear, smooth boundary. A2&Bt — 17 to 1!) inches, material in the A2 part is grayish- brown (lOYR 5/2) silt loam, and that in the Bt part is brown (lOYR 5/3) heavy silty clay loam; strong, medium to fine, subangular blocky structure ; firm ; many iron concretions ; very strongly acid ; abrupt, smooth boundary. B2&A2— 19 to 21 inches, material in the B2 part is brown (lOYR 5/3) heavy silty clay loam, and that in the A2 part is the same, except that it has coatings of gray (lOYR 6/1) on the structural pods; strong, medium to fine, subangular blocky and blocky structvu-e ; firm ; many iron concretions ; strongly acid ; abrupt, smooth boundary. B21t— 21 to 28 inches, grayish-brown (lOYR 5/2) silty clay loam to silty cla.y ; many, fine, prominent, olive-gray (5Y 5/2) mottles and common, fine, distinct, yellowish- brown (lOYR 5/0) mottles; strong, medium, prismatic structure breaking to strong, medium and coarse, angular blocky structure; very firm to firm; moder- ately thick, very dark gray (lOYR 3/1) clay films; some black llOYR 2/1) clay films in a few worm chan- nels ; common, fine pores ; many iron concretions ; strongly acid ; gradual, smooth boundary. B22t — 28 to 36 inches, olive-gray (5Y 5/2) heavy silty clay loam ; many, fine, prominent, yellowish-brown ( lOYR 5/4) and brownish-yellow (lOYR 6/8) mottles; mod- rate, medium, prismatic structure breaking to moder- ate, coarse, angular blocky structure ; moderately thick, dark-grav (lOYR 4/1) clav films and some very dark gray (lOYR 3/1) and black (lOYR 2/1) clay films on the peds ; man.y fine pores inside the peds ; firm to very firm ; many iron concretions ; medium acid : gradual, wavy boundar.v. B31t— 86 to 45 inches, light olive-brown (2.5Y 5/4) light silty clay loam ; common, coarse, prominent, yellowish- brown (lOYR 5/8) mottles and common, medium, faint, olive-gray (5Y 5/2) mottles; weak, coarse, pris- matic structure and some weak, coarse, angular blocky structure; firm; dark-gray (lOYR 4/1) clay films; man.v fine pores lined with very dark gray (lOYR 3/1) clay films ; iron concretions ; slightly acid ; clear, wavy boundary. B32t — 45 to 57 inches, light olive-brown (2.5Y 5/4) heavy silt loam ; many, coarse, prominent, yellowish-brown (lOYR 5/8) mottles and common, medium, prominent, olive-gray (5Y 5/2) mottles; massive to weak, coarse, blocky structure; some very dark gray (lOYR 3/1) and dark gray (lOYR 4/1) clay films on the vertical faces of the peds ; iron concretions ; slightly acid to neutral. Some areas of Cowden soils are ad.iacent to Piasa soils, and in places the Cowden soils are mapped in complexes with Piasa soils. The Cowden soils have a lighter colored surface layer than the Ilerrick soils, are somewhat darker colored than the Cisne soils, and are more poorly drained than the Oconee soils. They have a thinner A2 horizon than the Chauucey soils. Cowden silt loam (0 to 1 percent slopes) (112). — This soil has the profile described for the series. It is moderately well suited or well suited to the crops commonly grown in the county if it is well managed, if it dries out enough so that crops can be planted at the proi^er time, and if wet seasons are not prolonged. The principal crops are corn, soy 1 jeans, wheat, and clover. Erosion is not a hazard, but this soil is seldom plowed in fall. Where plowing is done in fall, the soil becomes com- pacted during winter and needs to be replowed before [)lanting time in spring. (Management group IIw-2, wood- land group 7) Cowden-Piasa complex, to 2 percent slopes (993A). — The soils of this complex have de\eloped in loess in the central and southern parts of the county. The complex consists of about equal proportions of a moderately dark colored Cowden soil and a light-colored Piasa soil. These soils occur in such an intricate pattern that it was not prac- tical to show the areas separately on the soil map. After a heavy rain, the Piasa soil can be easily distinguished in a plowed field because it has a much lighter colored sur- face layer than the Cowden soil (fig. 7). Also, its surface layer is smooth and compact, where the surface layer of the Cowden soil is rovigh and cloddy. The profile of the Cow- den soil is like the one described for the Cowden series. A representative profile for the Piasa soil is described un- der the Piasa series. Included with these soils in mappmg were a few areas of Ilerrick soils. Those areas were too small to be mapped sei)arately. Tlie Cowden soil has high available moisture capacity, and the Piasa soil has moderate available moisture capa- city. In years when the amount of rainfall is low to mod- erate, a shortage of moisture severely limits the growth of corn and soybeans on the Piasa soil. Also, the subsoil of the Piasa soil is alkaline in reaction and is high in ex- changeable sodium. Therefore, some plant nutrients held in the subsoil are not available to crops. As a result, crops grown on the Piasa soil show nutritional deficiencies sooner and to a greater degree than those grown on the Cowden soil. In many places the boundaries of the Cowden and Piasa soils can be determined by observing differences in the color of the crops grown on them. Both the soils have a low content of nitrogen and phosphorus. The Piasa soil is also low in potassium, l)ut the Cowden soil has a medium Figure 7. — A field consisting of soii.^ ui Cowden-Piasa complex, to 2 percent slopes. The dark-colored areas are the Cowden soil, and the light-colored ones are the Piasa. 18 SOIL SURVEY content of that element. Permeability of both soils is very slow. Because tile drains draw too slowly to remove much water, they are not suitable for draining- these soils, and ditches are needed. Proper fertilization is also important. If the soils are well managed, they are well suited to corn, soybeans, wheat, alfalfa, and other crops commonly grown in the county. (Management group IIIw-2, wood- land group T) Cowden-Piasa complex, 2 to 4 percent slopes, eroded (993B2). — This soil complex occurs along shallow, en- trenched drainageways in the glacial till plain. The soils are similar to those of Cowden-Piasa complex, to 2 per- cent slopes, but they are eroded. In places the plow layer is a mixture of material from the original surface layer and the subsoil. In many other places, it consists of clayey, alkaline material from the Piasa subsoil. Controlling erosion is difficult on these soils, but diver- sion terraces can be used in places to provide protection. In most areas keeping these soils in meadow a large part of the time reduces damage from erosion. Adequate fertiliza- tion is necessary for the satisfactory growth of plants. (Management group IIIw-2, Avoodland grou}) 7) Douglas Series Deep, dark-colored, well-drained soils that are gently sloping to rolling are in the Douglas series. These soils have developed in loess under prairie vegetation. They are on upland knolls and ridges on the glacial till plain. In most places the surface layer is about 8 inches thick and consists of very dark grayish-brov^n silt loam that has granular structure and is slightly acid to neutral in reaction. It is underlain by a layer of very dark grayish- In-own heavy silt loam, about 3 inches thick, that has gran- ular or subangular blocky structure and is also slightly acid to neutral. The subsoil, about 37 inches thick, is mainly brown to dark-brown silty clay loam that has sub- angular blocky stnicture and is medium acid to strongly acid. The underlying material is dark reddish-brown, mas- sive sandy loam and loam. The Douglas soils are in good tilth and are suited to a number of different crops, including corn, soybeans, wheat, oats, alfalfa, and clover. In most places erosion is a hazard, except in the least sloping areas. Permeability is moderate, and the available moisture capacity is high. Except in areas where the plow layer has received lime, reaction is medium acid to strongly acid throughout the profile. The content of organic matter and nitrogen is high, and the content of phosphorus and potassium is medium. Kepresentative profile of a Douglas silt loam (150 feet south and 30 feet east of the NW. corner of the SE40, SE160, sec. 22, T. 9 N., R. 2 W.) : Ai) — to 8 inches, very dark grayish-brown (lOYR 3/2) silt loam ; moderate, fine, granular structure ; friable : slightly acid to neutral ; abrupt, smooth boundary. A,3 — 8 to 11 inches, very dark grayish-brown (lOYR .3/2) heavy silt loam ; moderate, fine, granular to very fine, sub- angular blocky structure ; friable ; slightly acid to neutral ; clear, smooth boundary. Bl — 11 to 15 inches, brown to dark-brown (7.5YR 4/4) light silty clay loam; strong, very fine and fine, subangular blocky structure ; thick, very dark grayish-brown (lOYR 3/2) coatings on the surfaces of the peds, and these tend to mask colors inside the peds ; friable ; medium acid ; gradual, smooth boundary. B21t — 15 to 21 inches, brown to dark-brown (7.5YR 4/4) silty clay loam ; fine and very fine, subangular blocky structure; continuous dark-brown (7.5YR 3/2) clay films on the surfaces of the peds ; friable to firm ; strongly acid to medium acid ; gradual, smooth boundary. B22t— 21 to 28 inches, brown to dark-brown (7.5YR 4/4) silty clay loam; fine and meditim, subangular blocky struc- ture that has the aggregates arranged in weak prisms ; continuous, dark-brown (7. SYR 3/2} clay films on the surfaces of the peds ; friable to firm ; strongly acid to medium acid ; gradual, smooth boundary. B31— 28 to 38 inches, brown to dark-brown (7.5YR 4/4) light silty clay loam ; weak, coarse, subangular blocky structure that has the aggregates arranged in weak prisms ; most peds covered with thin, dark-brown (7.5YR 3/2) clay films; friable; medium acid; gradtial, smooth boundary. B82 — 38 to 48 inches, brown to dark-brown (7.5YR 4/4) heavy silt loam; common, fine, faint, brown (7.5YR 5/2) mottles ; massive and contains some cracks ; friable ; medium acid ; abrupt, smooth boundary. II Ab — i8 to 56 inches, dark reddish-brown ( 5YK 3/3) sandy loam ; massive ; firm ; medium acid ; gradual, smooth boundary. IIBb — 56 to 70 inches, dark reddish-brown (SYR 3/3) loam; massive ; firm ; medium acid. Many coarse pores, 1 to 5 millimeters in diameter, extend from the A3 horizon downward into the B3 horizons. Below a depth of about 50 inches, the texture varies but the soil material is sandy and porous in many places. In a few areas, the texture at that depth is heavy clay loam. The Douglas soils occtir with Pana soils, but the Douglas soils have a more silty texture. They are better drained than the Harrison soils. Douglas silt loam, 2 to 4 percent slopes (128B). — This soil occupies the less sloping parts of the ridges. It has the profile described for the series. This soil is suitable for field crops if practices are used that help to control erosion. If tillage is on the contour, row crops can be grown 2 years out of 3. If this soil is terraced, row crops can be grown 3 years out of 4 without serious losses from erosion. (Management grotip IIe-1, woodland group 7) Douglas silt loam, 4 to 7 percent slopes (128C). — This is a rolling soil on knolls and ridgetops in the central and eastern parts of the county. It is subject to erosion. Where tillage is on the contour, however, corn and soybeans can be grown 2 years out of 5. Row crops can be grown 2 years out of 4 if this soil is terraced. (Management grotip IIe-2, woodland group 7) Douglas silt loam, 4 to 7 percent slopes, eroded (128C2). — This soil is generally on the side slopes of knolls and ridges. Its surface layer is thinner than the one in the profile described for the series. In places the plow layer contains some material from the upper part of the subsoil that has been mixed w-ith the surface soil as the result of erosion and j^lowung. Included in mapping were small areas iit which the plow layer consists mainly of material from the subsoil. Those areas are less well suited to the crops commonly grown in the county than are the areas of typical Dotiglas soils. Where tillage is on the contour, corn and soybeans can be grown 2 years out of 5. If terraces have been installed, row crops can be grown 2 years out of 4 without risk of serious erosion. (Management group IIe-2, woodland group 7) Douglas silt loam, 7 to 12 percent slopes (128D). — This soil is on the higher parts of morainal knobs and ridges. MONTGOMERY COUNTY, ILLINOIS 19 In a few places, its surface layer is thinner than the one in the profile described for tlie series. Erosion is a serious hazard. If corn, soyl)eans, and otlier row crops are grown year after year, terraces are needed, or tillage needs to be done on the contour. (Management group IIIe-1, wood- land group 7 ) Ebbert Series The Ebbert series consists of deep, moderately dark col- ored, poorly drained soils that are nearly level and that develo})ed in loess under the infhu'uce of prairie vegetation. These soils occur throughout the prairie areas of the coun- ty but are most extensive in the central and southern parts. In places tliey are in depressions, where the slope is less than one-half percent. In many areas in the central and southern paits of the county, these soils occupy entire depressions. In most places the surface layer is about 8 inches thick. It consists of very dark gray silt loam that has granular or subangular blocky structure and is slightly acid to neu- tral in reaction. The subsurface layer, about 16 inches thick, is dark-gray silt loam to silty clay loam that has blocky structure and is slightly acid to medium acid in reaction. The subsoil is about 24 inches thick and is very dark gray in the upper part and gray mottled with yel- lowish brown and strong brown in the lower part. It has a texture of silty clay loam, has blocky structure, and is slightly acid to neutral in reaction. The underlying ma- terial is gray silt loam mottled witli yellowish brown and strong brown. It is massive and is neutral in reaction. Permeability is moderately slow or slow, and the avail- able moisture capacity is high. Surface runotf is slow in most areas. The content of organic matter, nitrogen, phos- phorus, and potassium is medium. Representative profile of Ebbert silt loam (30 feet south of the XW. corner of SW40, XW160, sec. 4, T. 12 X., R. 5 W., along the east side of the road) : Al — to 8 inches, very dark gray ( 10 YR 3/1 ) silt loam ; mod- erate, fine, subangular 'blo<:'ky and medium granular stnieture : friable ; slightly acid to neutral ; gradual, smooth boundary. A2— 8 to 24 inches, dark-gray (lOYR 4/1) silt loam to silty clay loam ; many, fine, distinct, dark reddish-brown (5YR 3/2) mottles; moderate, fine and medium, sub- angular blocky and angular blocli.y structure; friable: slightly acid to medium acid ; gradual, smooth boundary. B2tg— 24 to 36 inches, very dark gray (lOYR 3/1) silty clay loam: many, fine, prominent, dark yellowish-brown (10YR4/4) and yellowish-brown (lOYR.'./O) mottles; weak, medium, prismatic structure breaking to mod- erate to strong, medium, angular blocky and sub- angular blocky structure ; many dark-gray (lOYR 5/1) clay films ; firm ; slightly acid ; diffuse, smoioth boundary. B3tg— 36 to 48 inches, gray to light-gray (lOYR 6/1) light silty clay loam : many, medium, i^rominent, yellowish- brown (10YR.V6) and strong-brown (7..")YR 5/8) mot- tles ; weak, coarse, blocky structure : few dark-gray (lOYR 3/1) clay films; firm; many fine pores lined with dark gray (lOYR 3/1) ; neutral; diffuse, smooth boundary. C— 48 to 72 inches -f, gray to light-gray (lOYR 6/1) silt hjam ; many, medium, prominent, yellowish-brown (lOYR 5/6) and strong-brown (7.5YR 5/8) mottles; massive; friable ; neutral. In areas of these soils in the southern part of tlie county, the layer betweeia a depth of 4S and 72 inches is absent, and the B3tg horizon is underlain by gritty silty clay loam to clay loam till. In some places the texture in the Al and A2 horizons is heavy silt loam. In many places in the northern part of the county, Ebbert soils occur in depressions with Virden soils. Tliey have a grayer, more silty surface layer than the Virden soils and have a sub- surface layer that is lacking in the Virden soils. Ebbert silt loam (0 to 1 percent slopes) (48). — This is the only Ebbert soil mapped in this county. Its profile is the one described for the Ebbert series. Included in map- pifig were a few small areas of Piasa soils. If this Ebbert soil is drained and pro[)erly fertilized, it is suitable for corn, soybeans, wheat, and other crops com- monly growfi iti the county. Drainage can be improved by installing open ditches. Tile drains can also be used, but to be etfective, they must be placed at closer intervals than in most soils. (Management group IIw-2, woodland group?). Gullied Land Gullied land (Gu) is a miscellaiteous land type consist- ing of areas cut by gullies that are 3 to 10 feet deep. The gullies range from 6 to 20 feet in top width and cover at least half of the area. The soil inaterial is variable because the gullies expose several soil layers in most places. Most of the material exposed, however, is acid clay loam, cal- careous loam, and sandy loatn glacial till, hut it includes some material that contains excessive sodiutn. A cover of grass can be established on tliis land tyi)e by leveling, fertilizing, and seeding, but only small returns call be expected. An alternate treattnent is to plant the areas to shrubs and trees to be used for wildlife atid as wood- land. Because of the variability in depth of the gullies and the characteristics of the material exposed, a specific in- vestigation at each site should be made to determine ap- pro])riate uses. For tliis reason, Gidlied land has fiot been placed in a specific management group or woodland suit- ability group. Harrison Series In the Harrison series are dark-colored, moderately well drained, nearly level to sloping soils that developed in loess over glacial till under prairie vegetation. These soils are on small knolls and ridges, generally near small streams. They occur mainly in the northern and eastern parts of the county. In most places the surface layer is about 15 inches thick. It consists of very dark gray to very dark grayish-brown silt loam that has granular structure and is slightly acid to neutral ift reaction. The sul>soil to a depth of about 43 inches is mostly browti or very dark grayish browti in the upper part and light brownish gray in the loAver part. It has a texture of heavy silt loam or silty clay loam, gen- erally has blocky or subangular blocky structure, and is medium acid to slightly acid ui reaction. Beneath this soil material is grayish-brown gritty silty clay loam that is mottled with yellowish brown atid is neutral in reaction. These soils are moderately permeable and ha\e high available moisture capacity. They are generally tnedium acid to slightly acid throughout the profile and are medium in content of organic matter, nitrogen, phos- [)horus, and potassium. The Harrison soils are used nuiinly for corn, soybeans, wheat, oats, alfalfa, and other crops conimotdy grown in 20 SOIL SURVEY this county. Drainage is generally adequate for crops. Nevertheless, improvements in drainage would be bene- ficial in fields where these soils are farmed with wet soils, lle^jresentative profile of a Harrison silt loam (780 feet south and 40 feet east of the XW. corner of sec. 9, T. 11 N., R. 5W.): Al — to 15 inches, very dark gray to very dark grayish-brown (lOYll 3/1 or 3/2) silt loam ; moderate to strong, fine to medium, granular structure ; friable ; slightly acid to neutral ; clear, smooth Iwundary. Bl — 1.5 to 21 inches, very dark grayish-brown (lOYR 3/2) and brown to dark-brown (lOYR 4/3) silt loam; strong, mediiuii to fine, granular to subangular blocky struc- ture ; friable ; medium acid ; gradual, smooth boundary. B21t— 21 to 23 inches, brown to dark-brown (lOYR 4/3) light silty clay loam ; many, medium, distinct, pale-brown (lOYR G/3) mottles: moderate, medium and fine, sub- angular blocky structure; connuon. dark-gray (lOYR 4/1), thin clay films on the peds ; slightly firm; medium acid : gradual, smooth boundary. B22t— 2.S to 35 inches, brown to dark-brown (lOYR 4/3) silty clay loam ; many, medium, distinct, yellowish-red (5YR 4/S) mottles and common, fine, distinct, light brownish-gray (lOYR 6/2) mottles; moderate, me- dium, subangular blocky .structure ; clay Alms on the peds ; slightly firm ; medium acid, gradual, smooth boundary. B31— 35 to 43 inches, light brownish-gray (lOYR 6/2) heavy silt loam ; many, medium, prominent, yellowish-brown (lOYR 5/H) mottles: weak, coarse, angular blocky structure; common channels of gray (lOYR 5/1) ; few pebbles ; slightly acid ; gradual, smooth boundary. IIB32— 43 to 00 inches, grayish-brown (10 YR .5/2) gritty silty clay loam, glacial material ; many, coarse, distinct, yellowi-sh-brown (lOYR .5/8) mottles; some coatings and channel fillings of dark gray (lOYR 4/1) ; neutral. In many places the IIB32 horizon consists of grayish loess containing coarse, prominent, yellowish-brown to strong-brown mottles. The loess is massive and is neutral to alkaline in reaction. The Harrison soils occur with Ilerrick and Velma soils, but they are better drained than the Ilerrick soils, and unlike the Velma soils, they formed in loess. The Harrison soils are under- lain by less permeable material than the Douglas soils, and they are not so well drained as those soils. Harrison silt loam, to 2 percent slopes (127A). — In most places this soil has the profile described for the series. In the areas southwest of Hillsboro, however, the profile has a more brownish color than typical and resembles the profile of the Douglas soils. In sloping areas the slopes are convex and in those places this soil is at a higher elevation than the adjacent soils. Though the slopes are gentle, drainage is adequate for farming. This soil is well suited to a number of different crops, but it is used mostly for row crops, mainly corn and soy- beans. Erosion is not a hazard, and the only management practices necessary are tilling pr(jperly and applying com- mercial fertilizer and lime. (Management group I-l, wood- land group 7) Harrison silt loam, 2 to 4 percent slopes (127B). — This soil is on slight knolls and in areas adjacent to drainage- ways. Because of the gentle slopes, erosion is a hazard. The hazard can be reduced by tilling on the contour and using a cropping system that includes grasses and legumes for 2 years out of 5. If this soil is terraced, it can be used more intensively for corn and other row crops than where terraces are lacking. (Management group IIe-1, woodland groui) 7) Harrison silt loam, 2 to 4 percent slopes, eroded (127B2). — This soil occurs mainly near the heads of drain- ageways ^\-here erosion has been active. It has lost much of its original surface layer through erosion, and the present surface layer, about 8 inches thick, contains some material from the uppermost horizon in the subsoil. In many places all of the original surface layer has been lost and the pres- ent plow layer is brown silty clay loam. Terraces and con- tour tillage help to prevent even more serious erosion. A cropping system that includes meadow crops grown 2 years out of 5 is also desirable. (Management group IIe-1, wood- land group 7) Harrison silt loam, 4 to 7 percent slopes (127C). — This soil is on knolls and in areas adjacent to drainageways. It has not l>een seriously eroded in the past, but future ero- sion is a hazard unless careful management is used. Gro\y- ing meadow crops is one of the best ways of providing protection from erosion. If terraces have been installed, a suitable cropping system is one in which meadow crops are grown 1 year out of 4. Where this soil is farmed on the contour, a cropping system, in which meadow crops are grown 2 years out of 5 is generally adequate for controlling erosion. Where neither terracing nor contour tillage is used, a cropping system in which meadow crops are grown 3 years out of 5 is suitable. (Management group IIe--2, woodland group 7) Harrison silt loam, 4 to 7 percent slopes, eroded (127C2). — Erosion has removed pait of the original surface layer of this soil. In places the plow layer rests directly on the subsoil. In many areas the plow layer contains material from the subsoil that has been mixed into it by i)lowing. Because the present surface layer is thinner than the original one and contains only a small amount of nitrogen, crops grown on this soil often turn yellow. Including leg- umes and other meadow crops regularly in the cropping system helps to provide nitrogen. If terraces have been m- stalled, a suitable cropping system is one in which meadow crops are grown 1 year out of 4. Where this soil is farmed on the contour, a cropping system in which meadow crops are grown 2 years out of 5 is suifa))le. Where neither ter- racing nor contour tillage is used, meadow crops are needed at lea.st o years out of .-). (Management group IIe-2. wood- land group 7) Harvel Series The Harvel series consists of dark-colored, poorly drained soils that developed in loess under grass. These soils are in depressions and were naturally very poorly drained before drainage ditches were installed. They are mainly in the northern part of the county but also occur in other parts. The areas are small and generally occur within large areas of Virden soils. In most places the surface layer is about 10 inches thick. It consists of black silty clay loam that has angular blocky structure and is neutral to alkaline in reaction. Beneath the surface layer is a layer, about 11 inches thick, of dark- gray heavy silt loam that is massive and is mildly alkaline in reaction. The subsoil is about 35 inches thick and consists of dark-gray light silty clay loam that is nearly massive and is neutral in reaction. The underlying material is gray silt loam that is mottled with yellowish brown. It is mas- sive and is moderately alkaline. Harvel soils have high available moisture capacity and moderate permeability. They have a high content of or- ganic matter and a medium content of nitrogen, phospho- MONTGOMERY COUNTY, ILLINOIS 21 rus, and potassium. Tlie reaction is mildly alkaline. Drain- age has been improved. It could be further improved by installing additicmal tile di'ains in some areas. Representative profile of Harvel silty clay loam (40 feet east and 20 feet north of the SW. corner' of the NW40, NW160, sec. 17, T. 11 N., R. 4 W.) : Al— to 10 inches, black (lOYR 2/1) silty clay loam; weak, line, angular blocky structui'e; firm when moist, very sticky and very plastic when wet; neutral to alkaline; clear, wavy boundary. A3— 10 to 21 inches, dark-^ray (lOYR 4/1) heavy silt loam; a few, tine, prominent, dark reddish-brown mottles (SYR 3/4) and a few, coarse, prominent, strong-brown (7.5YR 5/G) mottles; massive; friable to firm when moist, slightly sticky and slightly plastic when wet; black (lOYR 2/1) coatings in root channels and large pores ; mildly alkaline ; gradual, smooth boundary. B2g— 21 to 56 inches, d;irk-gray (5Y 4/1) light silty clay loam or silt loam ; common, tine, prominent, yellowish- brown (lOYR .5/6) mottles; weak, coarse, subangular blocky structure ; firm when moist, very sticky and very plastic when wet ; about 40 percent of this hori- izon is composed of krotovinas, about 1 to 1% inclies in diameter and filled with dai-k-gray (5Y 4/1) heavy silt loam ; neutral ; gradual, smooth boundary. Cg — 56 to G5 inches, gray to light-gray (5Y 6/1) silt loam ; com- mon, tine, prominent, yellowish-brown (lOYR 5/6 to 5/8) mottles; massive; friable to firm when moist, slightly sticky and slightly plastic when wet; mod- erately alkaline. The A horizons range from 10 to 25 inches in combined thickness. They are thickest in areas where the Harvel soils grade towards Virden soils. The Harvel soils, unlike the Virden soils, have a subsoil mainly of silt loam. Harvel silty clay loam (0 to 1 i)ercent slopes) (252). — This is the only Harvel soil mapped in Montgomery Coun- ty. Its prohle is the one described for the series. Plowing when this soil is wet tends to compact the plow layer and to break down the structure. After the structure is broken down, the plow layer tends to pack and seal over so that air and water cannot enter easily. Where this soil is in poor tilth, grasses and legumes need to be included in the cropping system. Plowing is generally done in fall to avoid tillage when the soil is too wet in spring. Also, mel- lowing of the plow layer that takes place throughout the winter improves the seedbed. This soil is well suited to corn, soybeans, and other crops commonly grown in the county, but pro])er fertilization is needed. Most of the acreage is in corn and soybeans. (Man- agement group IIw— 1, woodland group 7) Hennepin Series Soils of the Hennepin series are well drained and are steep or verv' steep. They occupy the lower parts of valley walls, below areas of Hickory soils. Their original cover was a forest of hardwoods. In many places these soils have a darker colored surface layer than the Hennepin soils mapped in other counties. In areas where the surface layer is not seriously eroded, it is moderately dark colored. The material in which these soils developed is loam or sandy loam, calcareous till that was leached and weathered and subsequently was exposed as the result of headwater or streambank erosion. The darkening of the surface layer by accunuilated organic matter, and the leaching of free carbonates from the uppermost few inches of soil material, are the only ])rocesses of soil development that are appar- ent in the soil profile. In most places the surface layer is about 8 inches thick and consists of a very dark grayish-brown loam that has granular structure and is neutral in reaction. The subsoil, about 4 inches thick, is brown to dark-brown loam that has granidar structure and is mildly alkaline. The underlying material, to a depth of GO inches or more, is light yellowish- brown sandy loam that is massive or single grain and is calcareous. These soils are moderately perineable but have low avail- able moisture capacity. They are low to medium in natural fertility and are neutral to mildly alkaline in reaction. Hennepin soils are too steep for field crops and are tnainly in trees. Because of the alkaline reaction of the subsoil, however, pines do not grow well. The soils are well suited to pasture but are hard to mow and fertilize, because farm implements cannot be operated easily on the steep slopes. Representative profile of a Hennepin loam (66 feet west of bridge on countv road near the SE. corner of sec. 34, T. 8N.,lC4W.): Al — to S inches, very dark grayish-brown (lOYR 3/2) loam; strong, fine and medium, granular structiu-e ; friable ; few fine pebbles ; neutral : abrupt, wavy boundary. B— 8 to 12 inches, brown to dark-brown (lOYR 4/3) loam; moderate, medium and coarse, granular structure; friable ; few fragments of rock and rounded pebbles ; mildly alkaline: clear, smooth boundary. C— 12 to 60 inches, light brownish-gray (lOYR 6/2) sandy loam; about 10 percent, by volume, fine gravel; single grain ; firm when moist, nonsticky and nouplastic when wet; calcareous. In a few places, the A horizon is thicker than 8 inches. In other areas this soil is so eroded that calcareous glacial till is exposed. In this county the Hennepin soils occur with Hickory soils. Because they have the same kinds of slopes as the Hickory soils and occur in only small areas, they are mapped only in complexes with those soils. They lack the brown, leached sub- soil that is typical in the profiles of the Hickory and Velma soils. Herrick Series Deep, somewhat poorly drained soils that are dark col- ored and that developed in loess under prairie vegetation are in the Herrick series. These soils are nearly level and occur on the uplands. They are mainly in the northern and central parts of the county but are also extensive in the southwestern part. In the southwestern and central 2>iii'ts of the county, they are intermingled with Piasa soils. In most places the surface layer is very dark gray to black silt loam that is about 12 inches thick. It has granu- lar to fine subangular blocky structure and is neutral in reaction in the upper part and medium acid in the lower part. The subsurface layer is about 4 inches thick. It is dark gray or very dark gray silt loam that generally has sul)angular blocky structure and is strongly acid. The sub- soil, al)out 38 inches thick, is dark grayish-brown to dark yellowish-brown and olive-gray silty clay loam mottled with various shades of brown. It has subangular blocky and blocky structure and is strongly acid to neutral in re- action. The underlying material is olive-gray silt loam mottled with ^•arious shades of brown to yellowish red. It has prismatic structure or is massive and is slightly acid. Herrick soils have moderately slow permeability and high available moisture capacity. They have a high content of organic matter and a medium content of phosphorus 22 SOIL SURVEY and potassium. If these soils are properly managed, they are well suited to the crops commonly grown in the county. Representative profile of Herrick silt loam (510 feet south of center of road and 2/ii) mottles; moderate, fine, suliangular iilocky and blocky structure; when dry, has thick, grainy coatings of blanched silt on the peds ; friai)le; medium acid; clear, smootli boundary- B21t— 18 to 22 inches, dark .vellowish-brown (lOYR 4/4) silty cla.v loam ; common, fine, distinct, yellowish-brown (lOYR r)/6) mottles; moderate to strong, fine and medium, subangular and angular block.v structure; when dry, has thick, light-gray coatings of blanched silt around the peds; firm to friable; medium acid; clear, smooth boundary. B22t— 22 to 2!t inches, grayish-brown (2..")YR ."/2 ) heavy silty clay loam ; many. fine, prominent, yellowish-brown (lOYR .")/(> to ."')/4 ) mottles; strong, medium and fine, prismatic structure breaking to strong to moderate, medium, angular l)locky structure; thick, black (lOYR 2/1) and very dark gray ( lOYR 3/1) clay films; many fine tubular pores lined with clay films ; firm ; many very dark brown (lOYR 2/2 to 3/2) iron concretions; strongly acid ; gradual, smooth boundar.v. B23t — 29 to 40 inches, olive-gray and olive (.5Y .5/2 to 5/3) heavy silt.v clay loam ; man.v, fine, prominent, yellowish- brown ( lOYR ."i/4 to r»/6) mottles; moderate to strong, inediuin, prismatic structure breaking to moderate to weak, medium and coarse, angular block.v structure; black IIOYR 2/1) to very dark gray (lOYR 3/1) clay films ; firm when moist, sticky and verv plastic when wet ; medium acid ; gradual, smooth boundar.v. B24t — ^^10 to 47 inches, olive-gray (5Y 5/2) silty clay loam; many, fine, prominent, yellowish-brown (lOYR 5/4 to 5/6) mottles and a few, coarse, prominent, strong- brown (lOYR 5/8) mottles; moderate, coarse, pris- matic structure; thick, black and ver.v dark gray ( lOYR 2/1 to 3/1 ) clay films ; firm when moist ; slightly acid to neutral ; gradual, smooth boundary. B3t — 17 to .54 inches, olive-gra.v (5Y 5/2) silty clay loam ; many, medium, prominent, yellowish-brown ( lOYR 5/8) mottles and connnon, coiirse, prominent, strong-brown (7.5YR 5/8) mottles ; weak, coarse, prismatic struc- ture; firm; very dark gray (lOYR 3/1) clay films; neutral ; gradual, smooth boundary. C-54 to 65 inches, olive-gray ( 5YR 5/2 ) silt loam ; many, coarse, prominent, strong-brown (7.5YR 5/8) and .vellowish- red (5YR 5/8) mottles and common, coarse, prominent, dark yellowish-brown (10YR4/4) mottles; weak, very coarse, prismatic structure to massive; occasional cleavage planes lines with dark-gray (lOYR 4/1) clay films; friable to firm; slightl.v acid. In many places the upper B horizons are less brownish than tliose in tlie profile described. This is generally true of the Her- rick soils that are intermingled with Piasa soils. The platy structure described for the A2 horizon is not apparent in all areas. Herrick soils have a dark-gray subsurface horizon that is lacking in the Ipava and Virden .soils. Tliey are move poorly drained than the Harrison soils, and they lack the abrupt change in texture from the subsurface horizon to the subsoil that is typical of the Cowden soils. Herrick silt loam (46). — This nearly level soil has the profile described for the series. In most j^laces its drainage has been improved by installing tile drains and digging open ditches, but additional improvements in drainage are needed. Tillage is easy, and this soil can be tilled either in fall or in spring. It is well suited to corn, soybeans, wheat, oats, alfalfa, clover, and other crops commonly grown in the county. (Management group 1-2, woodland group 7) Herric'k'Piasa complex (995). — This soil complex con- sists of intermingled areas of a somewhat poorly drained, nearly level Herrick soil and a poorly drained, nearly level Piasa soil. These soils occur in such an intricate j)at- tern that it was not feasible to separate them on the soil map. In many places after a heavy rain, however, the Piasa soil in a recently plowed field can be easily distinguislied because its surface layer is lighter colored than that of the Herrick soil. The surface layer of the Piasa soil is also thinner than that of the Herrick soil. In addition, it has weaker structure. As a result, clods tend to slake down, making some areas have a smooth surface that is often called a slickspot. Unlike the Herrick soil and most other soils in the county, the Piasa soil has a subsoil that is alkaline and contains excessive exchangeable sodium. The profile of the Herrick soil is the one described for this series. A typical profile of the Piasa soil is described under the I'iasa series. Tlie soils of this complex are similar to tho.se of tlie Cow- den-Piasa and Cisne-Huey complexes in the pattern in which they occur. Typically, the Herrick and Piasa soils occur in about equal propoitions. In some areas, however, mostly in the northern part of the county, the Herrick soil is more extensive than the Piasa. Included with these soils in mapping were areas of Cowden soils that were too small to be mapped separately. The Herrick soil has high available moisture cai)acity, but the Piasa soil has only moderate available moisture \ capacity. Because of the greater amount of moisture it contains, the Herrick soil is better suited to crops than the Piasa, and it also contains more nitrogen, phosphorus, and potassium. "Wetness is a hazard wliere crops are grown on these soils. Tile drains are not effective in removing excess water from the Piasa soil, but open ditches can be used to improve the drainage of that soil. Tile drains could l)e installed in the areas that consist largely of the Herrick soil and that contain only a moderate acreage of Piasa soil. The soils of this complex are suited to corn, soybeans, wheat, alfalfa, and clover. They generally dry out so slowly in spring that they are not suital)le for oats. Be- cause the reaction of the Piasa soil is alkaline, moderate applications of phosphorus, applied frequently, give bet- ter results than large applications. (^Management group IIIw-2, woodland gi'oup 7) Hickory Series In the Hickory series are deep, liglit-colored, well- drained soils that have develojjed in loam glacial till of Illinoian age. These soils are rolling to very steep. They MONTGOMERY COUNTY, ILLINOIS 23 occupy valley walls aloiio- creeks in the parts of the county that were originally under forest. In most places the surface layer is about 2 inches thick. It is very dark orayish-brown loam that has granular structure and is slightly acid. The subsurface layer, about 8 inches thick, is strong-brown to brown loam that has subangular blocky structure and is strongly acid. The sub- soil is about 32 inches thick and consists mainly of strong- brown to brown clay loam tliat has subangidar blocky structure. It is strongly acid in the upper part and has neutral reaction in the lower part. The underlying mate- rial is calcareous brown loam to sandy loam and is massive. Hickory soils are moderately permeable and have mod- erate available moisture capacity. Their content of organic matter, nitrogen, and phosphorus is low, and their content of potassium is medium. In most places the reaction is strongly acid, but it is less acid in some places. Because many of the areas are steep and all of these soils are sus- ceptible to erosion, most of the acreage is wooded (fig. 8). Some areas have been cleared and are pastured, however, and a few areas are planted to annual crops. Representative profile of a Hickory loam (720 feet south and 40 feet east of the NW. corner of NW40, SW160, sec. 6,T.7N.,R.2W.): Al — to 2 inches, very dark grayish-brown (lOYR .3/2) loam ; weak, very fine, granular structure ; friable ; slightly acid ; abrupt, wavy boundary. A2 — 2 to 10 inches, strong-brown (7. SYR 5/Q) to brown (7.5YR •V4) loam; massive to weak, fine, subangular blocky structure; friable; small, irregular areas of material similar to that in the Al horizon are in the upper part of this horizon ; strongly acid ; gradual, smooth boundary. Bl — 10 to 14 inches, strong-brown (7..jYR5/G) to brown (7.5YR .5/4) heavy loam ; weak, medium, subangular blocky structure ; friable to tirm ; strongly acid ; gradual, smooth boundary. B2 — 14 to 20 inches, strong-brown (7.5YR .5/6) to brown (7.5YR .5/4) cliiy loam; weak to moderate, fine to ^yV, 4C-^i^: ■^^■W Figure 8. — Typical area of Hickory soils covered with oak and hickory trees, Hosmer soils ar« on the ridge in the background. 24 SOIL SURVEY medium, subangiilar blocky structure ; brown to dark- brown (7.5YR 4/4) clay films; firm; 5 percent of soil mass, b.v volume, consists of pebbles Vi incli to 3 inches in diameter ; most of the pebbles are hard and of mixed mineralogy, but some are weathered, are easily frac- tured, and originated from metamorphic and igneous roclvs : strongly acid : gradual, wavy boundary. B31 — 29 to 35 inches, strong-brown (7.5YR 5/(?) to brown (7.5YR 5/4) heavy loam; common, medium, distinct, pale-brown ( lOYR 6/3) mottles: weak, coarse, sub- angular blocky structure; brown to dark-brown (7.5 YR 4/4) clay films ; friable to firm ; about 5 percent, by volume, is pebbles ; strongly acid ; gradual, wavy boundary. B32 — 35 to 42 inches, strong-brown (7.5YR 5/6) to brown (7.5YR 5/4) loam; many, fine to medium, pale-brown (lOYR 6/8) mottles and a few, fine, distinct, light brownish-gra.v (lOYR 6/2) mottles; massive to weak, coarse, subangular blocky structure ; a few, brown to dark-brown (7.5YR 4/4) clay films in cracks; friable; neutral: abrupt, irregular boundary. C — 42 to 60 inches -|-, brown (lOYR .5/3) loam to sandy loam; massive ; firm and compact ; effervesces when dilute hydrochloric acid is added ; moderately alkaline. The combined thickness of the B horizons varies consider- ably, as does depth to the calcareous C hori^^on. In some areas of these soils at the top of the sloi>e, the carbonates in the C horizon have been leached to a depth of as much as SO to 100 inches. In other small areas, depth to the carbonates is only about 20 inches. In man.v places whei'e the carbonates have been leached to a great depth in the soils at the top of the slope, the soils are yellowish red instead of strong brown and are deeper than these soils in other ai-eas. They consist of a soil that was formerly buried but was subsecpiently exposed by geo- logic erosion. Hickory soils have a more brownish subsoil than the Blair soils, and the.v have a lighter colored surface la.ver than the Velma soils. They have a finer texture in the lower horizons than the Negley soils and are more deeply leached than the Hennepin soils. Hickory loam, 7 to 12 percent slopes (8D). — This soil lias tlie profile describerl for the series. Inclnded in niap- pino- were small areas of Hosmer soils and other soils that developed in loess on the upper parts of the slopes. This Hickory soil is suited primarily to meado^.v or pasture. It can be used occasionally for a row crop, how- ever, if terraces are used to protect it from erosion. (Man- ag-ement o-roup IIIe-1 . woodland o-roup 1 ) Hickory loam, 7 to 12 percent slopes, eroded (8D2). — In most places erosion has thinned the sitrface layer of this soil, and the combined thickness of the present surface layer and the subsurface layer is now only 5 to 8 inches. In a few places, the subsoil is exposed. Included with this soil in mappinp- were small areas of Hosmer soils and of other soils that developed in loess on the upper parts of the slopes. This Hickory soil is better suited to meadow than to row crops. If it is tilled on the contour or terraced, liowever, a row crop can be o-rown occasionally v.itliout risk of ser- ious erosion. (JNIanagement group IIIe-1, woodland group 1) Hickory soils, 7 to 12 percent slopes, severely eroded (8D3). — Erosion has removed all or nearly all of the original surface layer of this soil, and the present surface hiyer is brown loam to clay loam. In places all of the subsoil has been lost and the calcareous underlying material is ex]:)osed. These soils can be used for meadow, and occasionallj' they can be used for a row crop. More commonly, they are used for pasture or trees. Loss of the original surface layer, which lowers the moisture-supplying capacity, makes these soils only moderately well suited to any of these uses. (Management group IVe-1, woodland group 1) Hickory loam, 12 to 18 percent slopes (BE). — In jilaces the surface layer of this soil is less acid and is darlcer and thicker than the one in the profile described for the series. Also, in most places the profile is shallower over calcareous glacial till. This soil is so steep that it is generally used for pasture and trees. It is suited to meadow, however, and a row crop can 1)6 grown occasionally. (Management groTip IYe-1, woodland group 1) Hickory loam, 12 to 18 percent slopes, eroded (8E2). — Erosion has made the surface layer of this soil thinner than the one in the profile described for the series. In many small areas, erosion has removed all of the original sur- face layer and the subsoil is exposed. This soil is suitable for meadow, and it can be used oc- casionally for a row crop. j\Iore commonly, it is used for pasture or trees. (JManagement group IVe-1, woodland group 1) Hickory soils, 12 to 25 percent slopes, severely eroded (8E3). — These soils have lost most of their original surface layer, and the subsoil is exposed in many places. The pres- ent surface layer is loam to clay loam. In a few places, all of the subsoil has been lost and the calcareous glacial till is exposed. Tliese soils can be used for pasture or trees. They are only moderately Avell suited to pasture, however, because they have lost so much soil material from the surface layer. (^lanagement group VIe-1, woodland group 1) Hickory loam, 18 to 30 percent slopes (8F). — This soil has a profile that is similar to the one described for the series, except that the surface layer is darker and thicker in some places. Included with it in mapping were small areas in which limestone, sandstone, and shale are near the surface. These areas are mainlv east of Litchfield, alonir the vail ey of West Fork Shoal Creek. Nearly all of the acreage is used for pastures or trees. The pastures need to be fertilized, seeded to grasses and legumes, and well managed. (Management group VIe-1, woodland group 1) Hickory loam, 30 to 60 percent slopes (8G). — In many places tlie surface layer of this soil is darker, thicker, and less acid than the one in the profile described for the series. In those areas the subsoil is thinner than the one in the profile described for the series and calcareous glacial till is nearer the surface. This soil is shallow over limestone, sandstone, and shale in some places, especially in the areas east of Litchfield, near "West Fork Shoal Creek. It is used mainly for producing Avood products. (Management group VIIe-1, woodland group 1) Hickory-Hennepin loams, 18 to 30 percent slopes (997F). — This is a soil complex in which small areas of Hickory and Hennepin soils are so intermingled that show- ing them separately on the soil map was not feasible. The Hickory soil occupies about 80 percent of the mapped areas. It is on the upper part of the slopes, and the Henne- pin soil is mostly on the lower part. In places the Hennepin soil occurs in a discontinuous rather than in a continuous band. The Hennepin soil does not have a leached subsoil like the Hickory soil. The profile of the Hickory soil is the one described for the Hickory serie-;. A profile that is MONTGOMERY COUNTY, ILLINOIS 25 typical for tlie Hennepin soil is described under the Henne- pin series. Included witli these soils in mapping Avere areas of a soil that lies between the areas of Hickory and Hennepin soils and that has characteristics about half way between those of the Hickory and Hennepin soils. This included soil has a thick surface layer of dark grayish-brown loam and a thin subsoil of brown, leached light clay loam. It is underlain by calcareous sandy loam to loam glacial till that in most places is many feet thick. Because of tlie steep slopes and rapid runoff, the soils of this complex are subject to erosion. Nearly all of the acreage is in pasture or trees. The soils are well suited to imju'oved pasture, but good management of the pastures and woodland is needed for satisfactory returns. (]\Ianage- ment group VIe-1, woodland group 1 ) Hickory-Hennepin loams, 30 to 60 percent slopes (997G). — The Hickory soil is dominant in this complex; about 80 ])ercent of the acreage consists of Hickory loam. Kunotf is ra])id, and erosion is a hazard. The steep slopes limit the extent to which pastures can be improved and the kinds of management practices that can be applied. In general, these soils are much better suited to ti'ees than to pasture or Held crops. (IManagement group VIIe-1, woodland group 1) Hickory and Negley loams, 15 to 35 percent slopes (998F). — Tlie soils of this unit are well drained, light colored, and rolling to veiy steep. They occur in the same general areas, require similar management, and are used in the same ways. Therefore, mapping them separately did not seem practical, and they were mapped together in an un- differentiated unit of Hickory and Negley loams. The Negley soil does not occur in all ai-eas, and in most areas the Plickory soil is the more extensive of the tw^o soils. Both soils have developed mider forest and occur in areas , adjacent to the larger streams. The Hickory soil lias a pro- file like the one described for the series. The Negley soil has a profile like the one descril)ed for the Negley series. The soils of this unit have moderate availaljle moisture capacity. Tliey are low in content of organic matter, nitro- gen, and phosphorus and medium in content of potassium. The Hickory soil is moderately permeable, and the Negley soil is rapidly permeable. These steep soils are subject to erosion. They are used mainly for ti-ees and pasture. liunning farm machinery over them is hazardous because of the danger of over- turning. (Management group VIe-1, woodland group 1) Hosmer Series Soils that are light colored, moderately well drained, and gently sloping to I'olling are in the Hosmer series. These soils are on uplands, generally adjacent to the major streams. They have developed in loess and were originally co\'ered by a forest of mixed hardwoods. A slowly perme- able, dense layer, called a fragipan, is in the lower part of their subsoil. Eoots do not penetrate this layer, and the soils have no more than a moderately deep effective root zone. The unconsolidated material beneatli the fragipan extends to a considerably greater depth, liowever, than that to which roots can penetrate. In most forested areas, the surface layer is about 1 inch thick and consists of very dark gray silt loam that has granular structure and is slightly acid. The subsurface layer, about 5 inches thick, is dark grayish-brown silt loam tliat is massive in the upper part and has subangular blocky structure in the lower pAvt. It is very strongly acid. The upper part of the subsoil extends to a depth of al)0ut 28 inches and is very strongly acid to extremely acid. It is brown to dark yellowish-brown and has a texture of silt loam in the upper part and of light silty clay loam in the lower part. The lower part of the subsoil is about 35 inches thick, consists of mottled gray and brown silty clay loam to silt, loam, and is extremely acid to strongly acid. Hosmer soils are slowly jicrmeable and are subject to erosion because of the extensive runoff. They have moder- ate available moisture capacity and moderate natural fer- tility. The plow layer is very strongly acid, except in areas where lime has been added. In most places the content of organic matter, nitrogen, and phosphorus is low, and the content of potassium is low to medium. These soils are fairly w-ell suited to corn, soybeans, wheat, clo\-er, alfalfa, and other crops connnonly grown in the county. Control of erosion and proper fertilization are the major management needs. Representative profile of a Hosmer silt loam in a for- ested area (490 feet east and 122 feet north of the SW. corner of sec. 13, T. 9 N., R. 5 W.) ; laboratory data for this profile are given in Soil Survey Investigations Report for Illinois (see footnote 4, p. 16) : Ol — dark-brown to black, clecoiiiposed leaf litter. Al — to 1 inch, very darlc gray (lOYR 3/1) silt loam; mod- erate, fine to medium, granular structure ; very fri- able ; slightly acid ; clear, smooth boundary. A2 — 1 to 6 inches, dark grayish-brown (lOYR 4/2) silt loam; massive in upper part, but the structure grades to weak, fine, subangular blocky in the lower part ; fri- able; very strongly acid; clear, smooth boundary. Bl — 6 to 11 inches, brown to dark-brown ( lOYR 4/3) silt loam ; weak, fine to medium, subangular blocky structure ; friable; very strongl.y acid; clear, sn:ooth boundary. B21t— 11 to 17 inches, dark yellowish-brown (lOYR 4/4) light silty cla.v loam to silt loam ; weal^ to moderate, me- dium, subangular blocky structure ; friable ; distinct, fine patches of dark-brown (lOYR 3/3) clay films on the surfaces of the peds and in the ped interiors ; very strongly acid ; clear, smooth boundary. B22t— 17 to 23 inches, dark yellowish-brown (lOYR 4/4) light silty clay loam ; moderate, medium, subangnhir blocky structure l>reaking to strong, fine, angular blocky structure; thin patches of brown (lOYR .^/3) clay films on the surfaces of most peds and in the ped interiors ; friable to firm ; when dry, contains discon- tinuous small patches of blanched silt ; very strongly acid ; clear, smooth boundary. B23t— 23 to 28 inches, dark yellowish-brown (lOYR 4/4) light silty clay loam ; strong, medium and fine, subangular block.v and angular bloclvy structure : friable to firm : blanched silt coatings, 1 millimeter thick, are on the peds and form an apparently continuous network throughout the horizon, though they do not completely coat most individual peds ; extremely acid ; clear, smooth boundary. A'&B' — 28 to 33 inches, light brownish-gray (2..")Y 0/2, moist) and white (lOYR 8/1, dry) silt grains, which make up the A' horizon, coat the peds in the B' horizon. The B' horizon is mottled dark yellowish-brown (lOYR 4/4) and grayish-brown (lOYR 5/2) silty clay loam; .strong, fine to medium, blocky structure ar- ranged in moderate, medium prisms : firm : the few ped faces not coated with the gray silt have distinct, dark grayish-brown (lOYR 4/2) to dark .vellowish-brown (lOYR 3/4) clay films; extremely acid; clear, smooth boundary, B'2t— 33 to 41 inches, mottled grayish-brown (lOYR 5/2) and brown to dark-brown (7..jYR 4/4) silty clay loam; strong, medium, angular blocky structui'e, with the 26 SOIL SURVEY aggregates arranged in weak prisms ; distinct, dark yellowish-brown (lOYR 4/4) to dark grayish-brown (lOYR 4/2) olay films on the snrfaces of the peds; firm; extremely acid; gradual, smooth boundary. B'xl — 41 to 50 inches, light silty clay loam that is mottled in al)0ut equal proportions and in a tine, distinct pattern with gray (lOYR G/1) to grayish brown (2.5Y 5/2) and dark yellowish brown ( lOYR 4/4) to yellowish brown (lOYR 5/4) ; weak, medium, prismatic struc- ture breaking to weak, medium, angular l)locky struc- ture : distinct, nearly continuous, brown or dark-brown (lOYR 4/3) to dark yellowish-brown ( lOYR 3/4) clay films on the surfaces of the peds : spots of blanched silt, 1 to 5 millimeters in diameter, are apparent on the surfaces of the peds and in ped interiors : very firm ; extremely acid ; clear, smooth boundary. B'x2 — 50 to CO inches, heavy silt loam mottled in about equal proportions and in a fine to medium, distinct pattern with grayish brown (lOYR 5/2) and dark yellowish brown (lOYR 4/4) ; weak, coarse and very coarse, prismatic .structure ; very firm to extremely firm ; strongly acid ; clear, smooth boundary. IIB'xS— 00 to OS inches -f-, dark yellowish-brown (lOYR 4/4) gritt.v silt loam ; common, medium, distinct, dark grayish-brown ( lOYR 4/2) to grayish-brown (lOYR 5/2) mottles; massive; extremely firm; very strongly acid to strongly acid. Where this soil has been plowed, the material in the Al and A2 horizons is mixed, and the plow layer is dark grayish-l)rown (lOYR 4/2), friable silt loam that has weak, fine, crumb struc- ture. The horizon at a depth of 28 to 33 inches forms a distinct grayish zone in the profile. Hosmer soils occur with IMke, Stoy, Weir, and Hickory soils. They are not so well drained as the I'ike soils liut are better drained than the Stoy and Weir. The Hosmer soils developed in loess rather than in glacial till like the Hickory soils. They have a thinner surface layer than the O'Fallon soils and con- tain a subsurface layer that is lacking in the O'Fallon soils. Hosmer silt loam, 2 to 4 percent slopes (21 4B). — This g-eiitly i^lopiiig soil is mainly on rido-es. Its profile is the one described for the series. Tliis soil is moderately Avell suited to the crops commonly grown in the county, but it needs proper feitilization. If no erosion control practices are used, meadow crops grown one-third of the time help to protect the soil. Where tillage is on the contour and this soil is terraced, a cropping sys- tem in which grain crops are grown more than two-thirds of the tune can be used without causing excessive losses from erosion. (Management group IIe-3, woodlaitd group 2) Hosmer silt loam, 4 to 7 percent slopes (21 4C). — In most places this sloping soil is adjacent to drainageways. In a few places, however, it is on rounded knolls at a higher elevation than the surrounding soils. In general, the profile is the one described for the series. Included in map- ping, however, were a few small areas in which the surface layer is darker than the one in the prf)file described for the series. This Hosmer soil is moderately well suited to the crops commonly growit in the county, but it needs to be properly fertilized. Also, where cultivated crops are grown, terrac- ing, contour tillage, or other erosion control practices are needed. Where those ]>ractices are used, meadow crops need to be grown one-third of the time in the cropping system. If no practices are used that help to control erosion, a cropping system in which meadow crops are grown three- fifths of the time will generally protect this soil. (]\fan- agement group IIIe-2, woodland group 2) Hosmer silt loam, 4 to 7 percent slopes, eroded (214C2). — In most places this soil is adjacent to drainage- ways, but in a few places it is on rounded knolls at a higher elevation than the surrounding soils. It has a thinner sur- face layer than the one in the profile described for the series. In some places the plow layer consists of dark gray- ish-brown silt loam that has small lumps of yellowish- brown soil material from the subsoil mixed into it. In a few areas that are too small to be shown on the soil map, the plow layer consists mainly of material from the subsoil. Included with this soil in mapping were a few small areas of a soil that has a similar profile but that has a darker colored surface layer. Also included were a few small areas of a less sloping soil. Even if this Hosmer soil is well fertilized, it is only poorly suited to moderately well suited to crops. If culti- vated crops are grown, terracing, tilling on the contour, and other practices that help to control erosion are needed. If those practices are used, a cropping system in which this soil is used for meadow crops one-third of the time is needed to help control erosion. If no erosion control prac- tices are used, growing meadow crops more than half of the time will protect this soil. (Management group Ille- 2, woodland group 2) Hosmer soils, 4 to 7 percent slopes, severely eroded (214C3). — These soils are generally adjacent to drainage- ways. They are severely eroded, and the present plow layer is grayish-brown heavy silt loam or light silty clay loam that has much material from the sub.soil mixed into it. An abrupt boundary separates the ploAv layer from the sub- soil. In some places the subsoil is like the one in the profile described for the series, but it is thinner in many places and has a dense, compact fragipan nearer tJie surface. In those areas the a\ailable moisture capacity has been seri- ously reduced. The underlying glacial till is near the sur- face in many j^laces. The low content of organic matter and limitations re- sulting from severe erosion make these soils Ijetter suited to pasture or hay than to cultivated crops. Even Avhere the soils are well fertilized and well managed, they are poorly suited to only moderately well suited to the field crops com- monly grown in the county. If cultivated crops are grown, erosion control practices that include terracing and con- tour tillage are necessary. "W-liere those practices are used, a suitable cropping system is one in which these soils are used for meadow three-fifths of the time. (Management group IVe^l, woodland group 2) Hosmer silt loam, 7 to 12 percent slopes, eroded (214D2). — This rolling soil is adjacent to entrenched drain- ageways. It has a plow layer of dark grayish-brown to grayish-brown, friable silt loam. Beneath the plow layer is dark grayish-brown material like that in the i)rofi]e de- scribed for the series. In a few places, small lumps of yel- lowish-brown material from the subsoil are mixed with the other soil material in the plow layer. In some small areas, most of the plow layer consists of material from the .sub- soil. The underlying glacial till is at a depth of less than 40 inches in places. This soil is poorly suited to only moderately well suited to the field crops commonly grown \n the county, even though it is well fertilized. Where the erosion control practices include terracing and contour tillage, a cropping system in which this soil is used for meadow one-half the time will help to control erosion. If no erosion control ])rac- tices are used, this soil needs to be kept in pasture or hay. (Management grotip IIIe-2, woodland grouji 2) MONTGOMERY COUNTY, ILLINOIS 27 Hosmer soils, 7 to 12 percent slopes, severely eroded (214D3). — These rolliiio- soils are o-eiierivlly adjacent to en- treiiclied drainageways. Their plow layer has extended ; into the subsoil and consists of grayish-brown heavy silt I loam to light silty clay loam. Because the friable upper part of the subsoil is thinner than the comparable part of the profile described for the series, and the dense, compact fragipan is nearer the surface, the available moisture ca- pacity has been seriously reduced. Generally, glacial till is j also near the surface. j These soils are suited to liay and pasture if such prac- tices as terracing and contour tillage are used to help con- trol erosion. Even where tlie soils are properly fertilized 1 and well managed, however, returns are only low to mod- I erate. These soils are too droughty and susceptible to fur- i ther erosion to be well suited to the other crops commonly grown in the county. They can be used for trees and are well suited to pines. (Management group IVe-1, woodland group -2) Hoyleton Series Deep, moderately dark colored, somewhat poorly i drained soils that developed in loess under prairie vegeta- I tion make iip the Hoyleton series. These soils are nearly [' level to gently sloping and occur on uplands in the southern part of the county. They have a dense, compact claypan in i their subsoil. ! In most places the surface layer is about 8 inches thick ; aiul consists of very dark grayish-brown silt loam that has i granular structure and is strongly acid. Tlie subsurface I layer, about 8 inches thick, is mottled dark grayish-brown 1 to" brown silt loam that has granular structure and is very I strongly acid. The subsoil is about 2(\ inches thick and con- ': sists of silty clay loam to silty clay that has l)locky or sub- ': angular blocky structure. It is brown, mottled with yellow- isli red in the upi)er part and grayish brown to gray in the lower part, and it is extremely acid to strongly acid. ' The underlying material is gray to light-gray silt loam ■ that is massive and is neutral to moderately alkaline in I reaction. i Hoyleton soils are slowly permeable when they are fully moist, and they have high available moisture capacity. The I content of organic matter and nitrogen is moderate to low, ' and the content of available i)hosphorus and potassium is I low. Except where the plow layer has received lime, the surface layer is medium acid to strongly acid. These soils are suited to corn, soybeans, wheat, and other crops com- monly grown in the county. Representative profile of a Hoyleton silt loam (186 feet north and 15 feet east of the SE.' corner of NWIO, SE160, sec.2,T.7X.,R.2W.): All — () to ,S inches, very dark Krayish-hrowii (lOYR 3/2) silt loam ; weak, flue, granular structure ; friable ; strongly acid : abrupt, smooth boundary. A2 — S to 11 inches, dark j;rayish-brown (lOYR 4/2) to brown (lOYR 4/:^) silt loam: many, fine, faint, dark-brown (lOYR .■'>/.■{) mottles and a few, flne, distinct, brown to dark-brown (7..">YR 4/4) mottles; weak, flne, granular structure; friable; very strongly acid; abrupt, smooth boundary. Bit — 11 to 14 inches, brown (7..5YR 5/2) light silty clay loam ; common, flne, prominent, yellowish-red (SYR 4/6) mottles; strong, flne, subangular blocky structure; when dry, has many thick, white (lOYR 8/1) coat- ings of silty material on the peds ; flrm ; extremely acid ; abrupt, smooth boundary. B21t — 14 to 17 inches, grayish-brown (lOYR .5/2) silty clay; many, flne, prominent, red (2.r)YR 4/6) mottles; strong, flne, angular blocky structure; very flrm; ex- tremel.v acid ; gradu:il, smooth boundary. B22t— 17 to 26 inches, grayish-brown (lOYR .V2) silty clay loam to silty clay ; a few, flne, prominent, brown to dark-brown ( 7.r)YR 4/4) mottles and a few, fine, prom- inent, red (2. SYR 4/6) mottles; coarse, mediiun, pris- matic structure breaking to moderate, medium, angular blocky structure; thick, dark grayish-brown (lOYR 4/2) clay films; very firm ; very strongly acid; gradual, smooth boundary. B.3t— 26 to .37 inches, gray to light-gray (lOVR 6/1) heavy silt loam; many, flne, prominent, strong-brown ( 7..')YR 5/6) mottles; nearly massive, but contains a few large cracks; flrm; few dark-gray (lOYR 4/1) clay films in the cracks; many, flne, very dark gray (lOYR 3/1) veins; few pores lined with dark-gray ( lOYR 4/1) material; strongly acid; gradual, smooth boundary. CI— 37 to 50 inches, gray to light-gray (lOYR 6/1) silt loam; many, medium, prominent, yellowish-brown ( lOYR 5/6) mottles; massive; flrm; many fine, very dark gray (lOYR 3/1) veins and dark-gray (lOYR 4/1) clay films in a few cracks ; neutral ; gradual, smooth boundary. IIC2— 50 to 60 inches, gray ( lOYR 5/1 ) gritty silt lo:un : many, medium, prominent, dark yellowish-brown (lOYR 4/4) mottles; massive; friable; few fine pebbles; moder- ately alkaline. Hoyleton soils occiir with Cisne, Iluey, and Tamalco soils. They are better drained than the Cisne soils and do not have a mildly alkaline subsoil like the Iluey and Tamalco soils. The color of their surface layer is about halfway between that of the surface layer of the Oconee soils and the surface layer of the Stoy soils. Unlike the Oconee soils, they have red mottles in the upper part of the subsoil. Also, they developed In a thinner layer of loess. Hoyleton silt loam, to 2 percent slopes (3A). — This .soil occupies low crowns and is at a slightly higher eleva- tion than the adjacent soils. Its profile is the one described for the Hoyleton series. Water moves slowly through the l)rofile. Therefore, this soil remains too wet for tillage early in spring. No special practices are needed other than proper fertilization and good management. (Management group IIw-2, woodland group 7) Hoyleton silt loam, 2 to 5 percent slopes (3B). — This soil is gently sloping and needs some pi-otection from ero- sion. Managing crop residue well and keeping tillage to a minimum help to control erosioit. Keeping tliis soil in meadow 2 years out of 5 also controls erosion satisfactorily if contour tillage is practiced. Where contour tillage is not practiced, a cropping system in which meadow cro2:)s are grown half of the time is satisfactory. Terraces provide enough protection so that this soil can be used primarily for row crops. Because water moves slowly through the profile, this soil remains too wet for tillage early in spring. (Management group lie— t, woodland group 7) Hoyleton silt loam, 2 to 5 percent slopes, eroded (3B2). — This soil is mainly along drainageways, but it is on small knolls in a few places. Erosion has renio\ed part of the original surface layer. The present plow layer is very dark grayish brown and is thinner than the one in the pro- file described for the series. It rests directly on the subsoil. In some areas the surface layer is lighter colored tlian the one in the profile described for the series. This soil needs protection from further erosion. It will be much more difficult to manage if further erosion is al- lowed to remove the remaining surface soil, and if the plow layer then consists mainly of material from the subsoil. Managing crop residue well, keeping tillage to a minimum. 28 SOIL SURVEY choosing a suitable cropping system, and using other good nianagenient practices will help to control erosion. If no special erosion control practices are used, a cropping sys- tem in which meadow crops are grown one-half the time is suitable. Terraces can adequately control erosion, even though this soil is used mainly for row croj^s. (Manage- ment group IIe-4, woodland group 7) Hoyleton-Tamalco complex, 1 to 4 percent slopes (992B). — This soil complex consists of Hoyleton and Tamalco soils that are intermingled in an intricate pattern. The soils are gently sloping and are on ridges or side sloj^es along drainageways. They have profiles like the ones de- scribed for their respective series. The surface layer of the Tamalco soil is thinner than that of the Hoyleton soil. In- cluded in mapping were some areas that are nearly level. During periods of diy weather, crops do not grow so well on the Tamalco soil as on the Hoyleton. Because of the slow movement of water through the profile, some areas remain too wet for tillage early in spring, and some areas contain small seepy spots. These soils are only moderately well suited to tlie crops conmionly grown in the county, even though they are well managed and are properly fer- tilized. Practices are needed that help to control erosion. Where contour tillage and terracing are practiced, a cropping system in which these- soils are kept in meadow about two-fifths of the time controls erosion. If no erosion control practices are used, these soils need to be kept in meadow most of the time and a row crop grown only occa- sionally. Trees do not make satisf actoiy growth because of the alkaline reaction of the Tamalco subsoil. (Management group IIIe-3, woodland group 7) Huey Series The Huey series consists of light-colored, nearly level soils that are poorly drained and that developed in loess under a cover of grass. These soils are on iiplands in the southern part of the county. In most places the surface layer is about 8 inches thick. It consists of dark-gray silt loam that has platy or granu- lar structure and is slightly acid to neutral in reaction. The subsurface layer, about 2 inches thick, is grayish-brown loam that has platy structure and is medium acid. The subsoil is about 23 inches thick. It consists of gray silty clay loam that has columnar or prismatic structure and is mildly to moderately alkaline. The underlying material is gray heavy silt loam that is massive and is moderately alkaline and high in exchangeable sodium. These soils have low natural fertility. Their supplies of nitrogen and potassium are especially low, and their sub- soil is generally too alkaline for the phosphorus they con- tain to be available to plants. Available moisture capacity is moderate to low. These soils dry out slowly in spring. When they are fully moist, permeability is very slow. Mod- erate amounts of phosphorus and potassium, applied fre- quently, are more suitable for these soils than large amounts applied only occasionally. Open ditches are used to improve drainage, but the planting of crops is often delayed past the optimum period for planting, even where drainage has been improved. If these soils are properly fertilized, they are suited to corn, soybeans, and wheat. Eepresentative profile of a Huey silt loam (378 feet north and 100 feet west of the SE. corner of NW40, NE160, sec. 17,T.7N.,R.2W.): AiJ^O to 8 inches, dark-gray ( lOYR 4/1 ) silt loam ; weak to moderate, medium, platy structure brealving to weak, fine, granular structure ; frialtle when moist, nonsticky and uonplastic when wet ; sliglitly acid to neutral ; abrupt, smooth boundai-y. A2— 8 to 10 inches, grayish-brown (lOYR 5/2) silt loam; mod- erate, tliin, platy structure; friable when moist, non- sticky and very slightly plastic wheu wet; medium acid ; abrupt, wavy boundary. B21t— 10 to 14 inches, gray (lOYR 5/1 ), light-gray (lOYR 6/1), and a few areas of dark -gray (lOYR 4/1) silty clay loam ; common, tine, prominent, yellowish-brown (lOYR 5/6) mottles; massive to weak, coarse, columnar structure; sticky and plastic when wet; few chert peb- bles ; mildly alkaline ; gradual, smooth boundary. B22t— 14 to 24 inches, gray (2.5YR .5/1) silty clay loam; few, fine, distinct, strong-brown (7.5YR5/6) mottles; weak, coarse, prismatic structure ; very plastic and very sticky when wet ; modei-ately alkaline ; gradual, smooth boundary. B3t— 24 to .33 inches, gray (lOYR 5/1) silty clay loam ; strong- brown (7.5YR 5/6) mottles ; massive ; firm ; moderately alkaline; gradual, smooth boundary. C — .33 to 4.J inches, gray (lOYR .5/1) heavy silt loam; strong- brown (7.5YR 5/6) mottles; massive; friable; moder- ately alkaline. The A2 horizon is absent in many places. In those areas an abrupt boundary separates the Ap horizon from the B21t horizon. Huey soils occur with Cisne soils. They have a lighter colored, thinner surface layer than the Cisne soils and have a moder- ately alkaline subsoil, high in exchangeable sodium, that is lacking in the Cisne soils. The profile of the Huey soils re- sembles that of the Piasa soils, but the surface layer is lighter colored. In Montgomery County the Huey soils are in- termingled in an intricate pattern with the Cisne soils and are mapped with tliose soils. Ipava Series Deep, dark-colored, nearly level soils of the uplands are if! the Ipava series. These soils have developed in loess un- der the influence of prairie vegetation. They are in the extreme northwestern jjart of the county and in an area north of Butler. Natural drainage is somewhat poor, but response is good if additional drainage is provided. In most places the surface layer is about 12 inches thick. It consists of black to very dark gray silt loam that has granular structure and is neutral to slightly acid in reac- tion. The surface layer is underlain by a layer of veiy dark gray, mottled heavy silt loam that is about 5 inches thick, has granidar structure, and is medimn acid. The subsoil, about 28 inches thick, is mainly light yellowish-brown silty clay loam that is mottled with yellowish brown or with grayish brown. It has subangidar blocky and blocky struc- ture and is medium acid to slightly acid. The imderlying material is strong-brown, massive silt loam that is mottled with gray and is slightly acid. Ipava soils haA'e moderate permeability and high avail- able moisture capacity. They contain a large amount of plant nutrients and are .slightly acid to medium acid. Rep resent ati\^e profile of Ipava silt loam (990 feet soutli and 40 feet west of the NE. corner of sec. 7, T. 12 N., R. 5 W.) : Al— to 12 inches, black (lOYR 2/1) to very dark gray (lOYR 3/1) silt loam; strong, medium, granular structure; friable; slightly acid to neutral; gradual, smooth boundary. A3— 12 to 17 inches, very dark gray (lOYR 3/1) heavy silt loam ; few, fine, distinct spots of yellowish brown (lOYR 5/4) ; strong, medium, granular structure, friable ; medium acid ; clear, smooth boundary. MONTGOMERY COUNTY, ILLINOIS 29 B21t— 17 to 24 inches, light yellowish-brown (lOYR 6/4) light silty clay loam; common, line, distinct mottles of yel- lowish brown ( lOYR 0/8); moderate, medium, sub- angular blocky and angular blocky structure; thick, dark-gray (lOYK 4/1) coatings on the peds ; friable to firm ; medium acid ; gradual, smooth boundary. B22t— S4 to 34 inches, light yellowish-brown (lOYR 6/4) heavy silty clay loam ; many, fine, distinct, grayish-brown (lOYK 5/2) mottles; strong, medium, subangular blocky and angular blocky structure ; dark-gray ( lOYR 4/1) coatings on the peds; firm; medium acid; grad- ual, smooth boundary. B3t— 34 to 4.J inches, yellowish-brown (lOYR 5/4) light silty clay loam ; common, fine, distinct, yellowish-brown (lOYR rt/S) mottles; weak, medium to coarse, angular blocky and suliangular blocky structure; firm; root channels of very dark gray (10YR3/1) ; slightly acid; gradual, smooth boundary. C-4.") to 60 inche.s, gray (lOYR 5/1) silt loam; many, medium, prominent, strong-brown (lOYR 5/8) mottles and com- mon, medium, prominent, very dark gray (lOYR 3/1) mottles ; massive but contains a few cracks ; friable ; slightly acid. Ipava soils have a darker surface layer than Herrick soils. They also lack the subsurface layer that is typical in the Her- rick profile. Ipava silt loam (43). — This nearly level Ipava soil is the only one mapped in Montgomeiy County. Its profile is the one described for the series. Tile drains have been installed in most places, and drain- age has been improved to the extent that this soil can us- ually be tilled as soon after a rainy season as naturally better drained soils. It is well suited to corn and soybeans, and it is used mainly for those crops. Favorable soil tilth is not difficult to maintain, and plowing can be done in fall without danger of serious erosion or of excessive compac- tion taking place during winter. (IManagement group 1-2, woodland group 7) Landes Series Somewhat j^oorly drained, nearly level, moderately coarse textured soils that formed in alluvium make up the Landes series. These soils occur only in a few areas on the flood plains of the West and Middle Forks of Shoal Creek. Originally, they had a cover of mixed grasses and bottom- land hardwoods. In most places the surface layer is about 10 inches thick. It consists of veiy dark grayish-bi'own fine sandy loam that has granular structure and is neutral in reaction. Beneath the surface layer is brown to pale-brown fine sandy loam to loamy fine sand that is mottled with reddish brown and brownish gray to strong brown. It is structureless (single grain) and is slightly acid to neutral in reaction. The available moisture capacity is moderate to low, and permeability is rapid because of the high content of sand. Reaction is slightly acid to neutral. These soils have the col- ors of a somewhat poorly drained soil, though the water table remains high for only a few days each year. Flooding also occurs at times. It generally is not much of a hazard, however, because these soils ai-e at a somewhat higher ele- vation than the other soils on flood plains. About 1 year out of every 5, flooding occurs for short periods early in spring. The content of organic matter and nitrogen is medium, bvit the content of phosphorus and potassium is low. Representative profile of Landes fine sandy loam (200 feet southwest along a I'oad from a road brido'e near the center W.) : Al of sec. 36 and 20 feet south in a Held, T. 9 X., R. 5 to 10 inches, very dark grayish-brown (lOYR 3/2) fine sandy loam; weak, medium, granular .structure; very friable ; neutral ; abrupt, irregular boundary. CI — 10 to 14 inches, brown (lOYR 5/3) fine sandy loam ; single grain ; loose to very friable ; slightly acid to neutral ; gradual, smooth boundary. C2— 14 to 30 inches, pale-brown (lOYR 6/3) heavy loamy fine sand; many, medium, prominent, reddish-lirown (SYR 4/4) mottles and a few, fine, faint, light brownish- gray (lOYR 6/2) mottles; single grain; slightly acid; diffuse, smooth boundary. C3— 30 to .50 inches, light-gray (lOYR 7/1) loamy fine sand; many, medium, prominent, strong-brown (7.5YR 4/4) mottles ; very friable ; c(intains several layers in which the texture is loam ; slightly acid. Landes soils are not extensive in ^Montgomery County. They are coarser textured than the Lawson soils. The loamy fine sand that underlies the Landes soils in Montgomery County is nearer the surface than that underlying the Landes soils in other parts of Illinois. Landes fine sandy loam (304). — This is the only Landes soil mapped in Montgomery County. It is nearly level and occurs on the flood plains of the West Fork of Shoal Creek. The largest area is east of Litchfield. The profile is the one descril)ed for the Landes series. yiost of the water from rainfall is absorbed by this soil, and little water runs off. The water moves rapidly down- ward through the profile. As a result, only a moderate to small amotint is retained and made available to plants. A sandy soil, such as this one, cannot store the large amounts of plant nutrients that can be stored by a clayey soil. Because of the possibility of losses caused by leaching, therefore, applying moderate amounts of phos]:)horus and potassium to each crop is better than applying bulk ap]ili- cations. This soil has a medium supply of nitrogen, but nitrogen fertilizer is still needed, especially for corn. This soil is suited to corn and soybeans but is less well suited to clover, alfalfa, and wheat. Corn is presently the main crop. (Management group IIIs-1, Avoodland group 6) Lawson Series Soils that are deep, dark colored, and somewhat poorly drained are in the Lawson series. These soils have de- veloped in mixed silty and loamy alluvium on bottom lands throughout the county. Originally, they had a cover of mixed forest and grasses. In mo.st places the surface layer, about 18 inches thick, is very dark grayish-brown silt loam that has granular structure and is mildly alkaline. Beneath the surface layer is a layer of very dark gray gritty silt loam that is about 21 inches thick and has subangular blocky structure. At a depth of about 39 inches, that material, in turn, is under- lain by very dark gray loam that also has subangular blocky structure. Reaction is mildly alkaline throughout the profile, and lime is generally not needed. Though drainage is somewhat poor, the water table is usually low. At times it is high, however, for a short time after heavy rains, usually late in winter or early in spring. The available moisture capa- city is high, and permeability is moderate. The content of organic matter, nitrogen, phosphorus, and potassium is high. 30 SOIL SURVEY Representative profile of Lawsou silt loam (60 feet west and 25 feet north of bridge on i-oad in SWIO, SW40, SE160, sec. 21, T. 9 N., R. 3 W.f: All— to 18 inches, very dark gra.yisli-l)ro\vn ( lOYR 3/2) silr loam: weak, line and niediuni, granular strnc-ture: friable : few small pebbles : mildly alkaline : gradual, smooth boundary. A12— 18 to 39 inches, very dark gray ( lOYR 3/1 ) gritty silt loam; weak, medium, subangular bloiky structure: friable: few small pebbles: mildly alkaline; diffuse, smooth boundary. A13— 39 to .")3 inches +, very dark gray (lOYR 3/1) loam, weak, medium, subangular blocky structure; friable: few small pebbles ; mildl.v alkaline. In many places these soils are lighter colored below a depth of 24 inches than is indicated in the profile described for the series. In those areas the colors range from dark gray to dark grayish brown. The surface layer of typical Lawson soils con- tains enough sand to give it a gritty feel. The Lawson soils lack the underlying layer of silty clay loam that is typical in the profile of the Radford soils. Lawson silt loam (0 to 2 percent slopes) (451). — This is tlie only La\vson soil mapped in Montgomery County. It is on l)ottom lands and is nearly level. Included with this soil in mapping were a few small areas of a soil that contains layers of sandy loam that are generally less tlian 8 inches thick. Also included were a few areas in which sand is within 40 inches of tlie surface. Other inclusions consist of small areas that are covered l)y a layer, as much as 12 inches thick, of light-colored, recently deposited silt loam that has Avashed from the adjacent ui)lands. Lawson silt loam is fre(|uently flooded, but the flood- waters generally remain for only a short time. Flooding normally occurs early in si)ring, but it occurs occasionally in fall. When flooding occurs in fall, crops that are not yet harvested are damaged. This soil is used mainly for corn and soybeans, but some areas that are least susceptible to flooding are used for small grains and red clover. Diversion terraces and open ditches can be used to help keep runoff from spreading out over this soil and causing damage. In some areas where flooding is infrequent and does not last long, and where the soil does not contain lavers of sand, tile drains can be used to improve drainage. Where this soil contains layers of sand, however, it is not suited to tile drains, because the sand washes into the drains and fills them. (Management group 1-3, woodland group 6) Negley Series The Negley series consists of well-drained, rolling to very steep, light-colored soils that developed in coarse- textured glacial material, principally sand and gravel. These soils are adjacent to streams and on rounded knolls in the uplands. They are in the southern and eastern parts of the county, in areas that originally were covered with forests of mixed hardwoods. In most places the surface layer is about 6 inches thick and consists of dark grayish-brown loam that has granular structure and is slightly acid to neutral m reaction. The subsurface layer, about 3 inches thick, is dark-brown to brown loam that has satbangular blocky structure and is medium acid. The subsoil is about 39 inches thick and is reddish-brown to brown loam to sandy clay loam. It has subangular blocky structure and is medium acid to very strongly acid. The underlying nuvterial is brown ]tea\-y sandy loam that is massive and is strongly acid. Permeability is moderately rapid, and the available moisture capacity is moderate. The reaction is medium acid to strongly acid. In general, these soils are low in content of organic matter, nitrogen, phosphorus, and potassium. Meadow^ crops can be grown on some of the rolling areas. Most of the areas are too steep for meadow, however, but are suitable for trees or pasture. Pines grow well on these soils. Representative profile of a Negley loam (450 feet east of the NW. corner of SW160, sec. 28,"T. 8 N., R, 4 W., along south side of a private road) : Al — to 6 inches, dark grayi.sh-brown (lOYR 4/2) loam: strong, fine, granular structiu-e ; friable ; slightl.v acid to neutral ; abrupt, broken boundar.v, A2 — 6 to 9 inches, dark-brown to brown (T.oYR 4/4) loam: weak, fine, subangular blocky .structure ; friable ; medium acid ; abrupt, broken boundary. Bit — 9 to 13 inches, reddish-brown (5YR 4/4) loam; moderate, medium, suliangular blocky structure: friable; strongly acid to medium acid ; gradual, smooth boundary. B2t — 13 to 30 inches, reddish -brown (.5YR 4/4) saud.v cla.y loam : mr)derate to weak, subangular block.v structure: friable when m()ist, .sticky and plastic when wet : very strongly acid ; gradual, smooth boundar.v. B3t — 36 to 48 inches, brown (7. SYR ~>/4) heavy sandy loam or light sandy clay loam: weak, coarse, angular block.v structure, with reddish-brown ( ."iYR 4/4) clay films on the faces of the peds ; friable when moist, nonsticky and nonplastic when wet ; strongly acid ; diffuse, smooth lioundary, C — 48 to 109 inches -f. brown (7.5YR 5/4) heavy .sandy loam to .sandy cla.y loam ; massive ; friable when moist, non- sticky and nonplastic when wet; strongly acid. Pebbles less than 1 inch in diameter constitute 10 to 20 i>er- cent of the soil mass. In many places the (' h(u-izon consists of loose sand or gravel that in places is calcareous. Negley soils occupy small areas adjacent to or within areas of Hickory soils. Becau.se the Negley soils and some areas of Hick(U-y soils are steei» and are used and managed in the same way, they have been mapped in an undifferentiated unit, which is described under the Hickory series. Nokomis Series Dark-colored, somewhat poorly drained, gently sloping soils that developed in mixed silty and loamy alluvial ma- terial are in the Nokomis series. These soils are on alluvial fans and stream terraces in the valleys of the major streams througliout the county. Originally, tliey had a cover of mixed grasses and bottom-land hardwoods. In most places the surface layer is about 9 inches thick and consists of black silt loam to loam. It has graiudar structure and is slightly acid to neutr-al. The subsurface layer, about 7 inches thick, is mottled grayish-brown silt loam to loam that has subangular blocky structure. It is slightly acid to neutral in reaction. The subsoil is 34 inches or more thick, is grayish brown in the upper part and gray in the lower part, and is mottled with strong brown. It has a texture of lieavy loam to silty clay loam, has subangular blocky structure, and is neutral to medium acid in reaction. Nokomis soils have the typical grayish color of some- what poorly drained soils, but a high water table limits the growth of crops only during extremely wet periods. These soils are moderately |>ermeable and have high avail- MONTGOMERY COUNTY, ILLINOIS 31 able moisture capacity. They liave a medium content of organic matter, phosphorus, and potassium. Representative profile of Nokomis silt loam (216 feet south along a field boundary west of a highway bridge over East Fork Shoal Creek in'the NEIO, SWiO, NW160, sec. 31,T.8N.,R.2W.): Al— to 9 inches, black (lOYR 2/1) silt loam to loam; mod- erate, medium, granular structure ; friable ; slightly acid to neutral ; abrupt, irregular boundary. A2— 9 to 16 inches, grayish-brown (lOYR 5/2) silt loam to loam; a few, medium, prominent, brown to dark-brown (7.5YR 4/4) mottles and many, fine, faint, brown (lOYR 5/3) mottles; weak, medium, subangular blocky structure ; friable ; slightly acid to neutral ; diffuse, smooth boundary. Bit — 16 to 40 inches, grayish-brown (lOYR 5/2) heavy loam to light clay loam ; common, medium, prominent, strong-brown (7.5YR 5/6) mottles and a few, fine, prominent, black (5YR 2/1) mottles; moderate, me- dium, subangular blocky structure ; when dry, peds are coated with light-gray (lOYR 7/1) sand grains; friable to firm ; slightly acid to neutral ; clear, smooth boundary. B2t — iO to 50 inches, gray (lOYR 5/1) gritty light silty clay loam; many, coarse, prominent, strong-brown (7.5YR 5/4 to 5/8) mottles; massive, but contains some large cleavage planes; thin, gray (lOYR 5/1) clay films in the cleavage planes ; firm ; few small pebbles; common large pores ; medium to slightly acid. Tlie content of silt and sand throughout the profile varies considerably. In many places the texture is loamy throughout the profile, but it is gritty silt loam in places. Nokomis soils are not so well drained as the Terril soils and are darker colored than the Starks and Camden soils. They have a slight accumulation of clay in the subsoil that is lack- ing in the subsoil of the Lawson soils. Nokomis silt loam (1 to 3 percent slopes) (586). — This is the only Xokomis soil mapped in Montgomery County. It is gently sloping and occurs on alluvial fans and stream terraces. The profile is the one described for the series. Included in mapping were a few areas in which the slopes are slightly .steeper than 3 percent, and a few areas in which the i)rofile contains layers of sandy loam. Because Nokomis silt loam is at a slightly higher eleva- tion than the surrounding soils of the bottom lands, it normally is not flooded. During periods of severe overflow, hoAvever, some areas are flooded for short periods. In places diversion ditches are needed to keep water that runs off the adjacent higher lying soils from spreading out over this soil and causing damage. Erosion is not a serious hazard. This soil is moderately well suited to well suited to the crops commonly grown in the county, but it needs proper fertilization and good management. K can be used for hay, pasture, or trees, but most of the acreage is m corn and soybeans. (Management group 1-2, woodland group 5) Oconee Series The Oconee series consists of deep, moderately dark colored, nearly level to sloping soils that are somewhat poorly drained. These soils have developed in loess under prairie vegetation and are on uplands in the central and southern parts of the county. They have a dense, compact subsoil, commonly called a claypan. In most places the surface layer is about 8 inches thick. It consists of very dark gray to dark grayish-brown silt loam that has granular structure and is medium acid to slightly acid. The subsurface layer, about 7 inches thick, 294-384—69 3 consists of grayish-brown silt loam. It has platy structure and is strongly acid to very strongly acid. The subsoil, about 35 inches thick, is grayish-brown, brown, and yel- lowish-brown silty clay loam that is mottled with gray and yellowish brown and has blocky structure. The upper part of the subsoil is very strongly acid, but the reaction ranges to slightly acid in the lower part. Because of the slight to moderate slopes, water drains readily from the surface of these soils ui most places, but it percolates slowly downward after the soils are wet. As a result, these soils dry out slowly in spring. The planting of crops, especially oats, is often delayed. The available moisture capacity is high. The content of phosphorns and potassium is low, and the reaction is strongly acid, except where the plow layer has receiA^ed lime. These soils are well suited to corn, soybeans, wheat, and other cultivated crops commonly grov\ai in the county. Representative profile of an Oconee silt loam (342 feet west of the junction of a county road and State Route 127 and along the south right-of-way of the road in sec. 29, SE160, NW40, NWIO, T. 10 N., R. 4 W.) : Al — to 8 inches, very dark gray (lOYR 3/1) to dark grayish- brown ( lOYR 4/2 ) silt loam ; moderate, fine, gi-anular structure ; friable ; medium to slightly acid ; clear, smooth boundary. A21— 8 to 12 inches, grayi.sh-brown (lOYR 5/2) silt loam; weak, thin, platy structure ; friable ; strongly acid to very strongly acid ; clear, wavy boundary. A22— 12 to 15 inches, grayi.sh-brown (lOYR .5/2) silt loam; weak to moderate, thin, platy structure, with many coatings of gray to light gray (lOYR 6/1) on the structural aggregates ; friable ; strongly acid to very strongly acid ; abrupt, smooth boundary. B21t— 15 to 28 inches, grayish-brown (lOYR 5/2) silty clay loam to isilty clay ; few, fine, prominent, yellowish- brown (lOYR 5/6) mottles; moderate, fine, angular blocky structure, with continuous, thin, grayish- brown (lOYR 5/2) clay films on the surfaces of the structural aggregates ; firm when moist, plastic when wet ; very strongly acid ; clear, smooth boundary. B22t— 28 to 43 inches, brown (lOYR 5/3) silty clay loam; many, fine, distinct, gray (lOYR 5/1) mottles and a few, fine, prominent, yellowish-brown (lOYR 5/8) mottles; very weak, fine and medium, angular blocky structure; a few, thin, grayish-brown (lOYR 5/2) clay films ; firm when moist, plastic when wet ; strongly acid ; gradual, smooth boundary. B3t— 43 to .50 inches, yellowish-brown (lOYR .5/4) silty clay loam to silt loam ; many, fine, distinct, light brownish- gray (lOYR 6/2) mottles and a few, medium, promi- nent, strong-brown (7.5YR .5/6) mottles; massive; firm ; few fine pores filled with very dark gray (lOYR 3/1) clay films; medium acid to slightly acid. In places the reaction in the B22t horizon ranges to mildly alkaline below a depth of 40 inches. Oconee soils occur with O'Fallon soils in many places, but they lack the friable upper subsoil that is typical in the O'Fallon profile. The Oconee soils are better drained than the Cowden soils, and they have developed in a thicker layer of loess than the Hoyletou soils. Their profile is similar in many respects to that of the Hoyleton soils, but it lacks reddish colors in the upiier part of the subsoil. Oconee silt loam, to 2 percent slopes (113A). — ^This soil has the profile de.scrilied for tlie series. In most places it is on small rises, at a slightly higher elevation than the surrounding soils. This soil is well suited to corn, soybeans, and wheat, and the cropping system generally used is one in which those crops are grown most of the time. In most places the slight slope provides adequate surface drainage. (Management group IIw-2, woodland group 7) 32 SOIL SURVEY Oconee silt loam, 2 to 4 percent slopes (113B). — This soil is on low knolls and in areas adjacent to small drain- ageways. It is mainly in the central and southern parts of the county. Erosion is a hazard. Therefore, this soil needs to be used for meadow occasionally, even though such practices as terracing and tilling on the contour are used to help con- trol erosion. Where tillage is not on the contour, a suitable cropping system is one in which this soil is kept in meadow about half the time. (Management group IIe-4, woodland group 7) Oconee silt loam, 2 to 4 percent slopes, eroded (1 13B2). — This gently sloping soil is generally adjacent to small drainageways. Erosion has removed part of the orig- inal surface layer. The present plow layer is very dark grayish-brown silt loam, and it rests upon the uppermost layer of the subsoil. In some places the plow layer con- tains some material from the subsoil that has been mixed into it as a result of erosion and subsequent plowing. In- cluded in mapping were small areas in which the plow layer now extends into the upper part of the subsoil. Contour tillage and terraces help to prevent further ero- sion of this Oconee soil. (Management group IIe-4, woodland group 7) Oconee silt loam, 4 to 7 percent slopes (113C). — In places this sloping soil is on slight knolls, but it generally occupies areas adjacent to small drainageways. The sur- face layer is somewhat thinner than the one in the profile described for the series, and it is dark grayish brown. A few small areas of Tamalco soils were included in this map- ping unit. This Oconee soil is subject to serious erosion. It can be protected from erosion by practicing contour tillage, terracing, and using a cropping system in which meadow crops are grown one-third of the time. (Management group IIIe^2, woodland group 7) Oconee silt loam, 4 to 7 percent slopes, eroded (1 13C2). — This is a sloping soil adjacent to small drainage- ways. Erosion has removed part of the original surface layer, and the present plow layer is very dark grayish brown. In many places the present surface layer contains small lumps of subsoil that have been mixed into it by plowing. It rests directly on the subsoil. Included with this soil in mapping were small areas in which the grayish-brown subsoil is exposed. In those areas plowing is mainly in the subsoil. Erosion control practices, such as contour tillage and terracing, are needed. Those practices and using a cropping system in which meadow crops are grown at least one-third of the time help to control erosion. (Management group IIIe-2, woodland group 7) Oconee-Tamalco complex, to 2 percent slopes (994A). — This soil complex consists of a somewhat poorly drained Oconee soil and a moderately well drained Ta- malco soil. These soils occur in such an intricate pattern that separating them on the soil map was not feasible. The proportions of each soil vary considerably from place to place. In many areas the proportions of Oconee and Ta- malco soils are about equal, but in others one soil is much more extensive than the other. These soils are on small knolls and ridges, as well as in areas adjacent to streams. They are mainly in the central and Avestern parts of the county, generally at a sliglitly higher elevation than the surroundinsf soils. The dominant slopes are between 1 and 2 percent, and the average length of the slopes is about 200 feet. The surface layer of these soils ranges from 7 to 14 inches in thickness, but the Tamalco soil has a thinner sur- face layer than the Oconee. Both of these soils have a mod- erately dark colored surface layer, but the Tamalco soil has a somewhat lighter colored surface layer than the Oconee. This is most noticeable in a recently plowed field after a heavy rain. The lower part of the Tamalco subsoil, unlike that of the Oconee, is alkaline and is high in content of exchangeable sodium. The profile of the Oco- nee soil is similar to the one described for the Oconee series. A typical profile of the Tamalco soil is described under the Tamalco series. Some areas of these soils are too wet for tillage early in spring because the downward movement of water through the profile is slow. Especially during periods of dry weather, crops do not grow as well on the Tamalco soil as on the Oconee. The Tamalco soil has somewhat lower available moisture capacity than the Oconee because roots cannot penetrate the dense lower subsoil. Also, the alkaline reaction in the lower part of the Tamalco sub- soil limits the availability of phosphorus and potassium. Because of deficiencies in those elements, the pattern in wliich tliese soils occur can be seen in many fields if one observes the color and height of the plants in dift'erent areas. In some places corn growing on the Tamalco soil, for example, is purple instead of green, and alfalfa and clover are bluish green instead of the normal green that is typical of crops growing on soils that have better mois- ture-supplying and nutrient-supplying capacities. The soils of this complex are used mainly for field crops and meadow, but they need good management and proper fertilization. Even after they have been properly managed and fertilized, however, they are still not well suited to the crops commonly growui in the county. (Man- agement group IIw-2, woodland group 7) Oconee-Tamalco complex, 2 to 4 percent slopes (994B). — The soils of this complex are gently sloping and occupy convex ridges and areas adjacent to drainageways. Their profiles are like the ones described as representa- tive for the Oconee and Tamalco series. Usually, the Tam- alco soil can be distinguished from the Oconee by its thinner surface layer and by tlie poorer growth of crops. Permea- bility of the Tamalco soil is slower than that of tlie Oconee soil. Therefore, the Tamalco soil often remains wet for longer periods after rains than does the Oconee soil. These soils are used mainly for growing grain and mea- dow crops. Practices are needed that help to control ero- sion. Wliere contour tillage and terracing are practiced, a cropping system in which meadow crops are grown about two-fifths of the time helps to control erosion. If those practices are not used, a suitable cropping system is one that consists mainly of meadow crops. (Management group IIIe-3, woodland group 7) Oconee-Tamalco complex, 2 to 4 percent slopes, eroded (994B2). — This soil complex consists of sloping soils on convex ridges and in areas adjacent to drainageways. The profiles of these soils are similar to the ones described for the Oconee and the Tamalco series. The s^ibsurface layers have been incorporated in the plow layer, however, as a result of plowmg and erosion. The Tamalco soil is more eroded than the Oconee. It can be distinguished from the Oconee soil by its thinner surface layer and by the poorer MONTGOMERY COUNTY, ILLINOIS 33 growth of crops during periods of dry weather. Included with these soils in mappmg were small areas in which the plow^ layer consists mainly of material from the subsoil. Water moves slowly downward in the soils of this com- plex. As a result, some areas remain too wet for tillage early in sprmg, and some areas contain small localized seepy spots. Their undesirable characteristics make these soils only moderately well suited to the grain crops commonly grown in the comity, even though good management is used and the soils are properly fertilized. Practices that help to control erosion are needed. ^Vliere tillage is on the contour and terraces have been installed, using a cropping system in which meadow crops are grown about two-fifths of the time helps to control erosion. If no practices are used that provide protection, using the soils mauily for meadow, and growing a row crop only occasionally, will help to control erosion. (Management group IIIe-3, woodland group 7) Oconee-Tamalco complex, 4 to 7 percent slopes, eroded (994C2). — In this soil complex are sloping soils on ridges or in areas along drainageways. The i^rofiles are similar to the ones described for the Oconee and Tamalco series, except that the subsurface layers have been incor- porated in the plow layer as the result of plowing and erosion. The Tamalco soil contains a greater number of eroded, bare spots than the Oconee soil. It has a plow layer of grayish-brown silt loam that in many places has small lumps of brown material from the subsoil mixed into it. Included in maj^ping were small areas in which the plow layer consists mainly of material from the subsoil. Because most of the surface layer has been lost through erosion, the capacity for storing water has been reduced in the soils of this complex. The available moisture capac- ity is moderate to low, but it is lower in the Tamalco soil than in the Oconee. As a result, the Tamalco soil can gen- erally be distinguished from the Oconee by the poorer growth of crops during periods of diy weather. A greater amount of water runs off these soils and less water soaks in than in the soils of other Oconee-Tamalco complexes. These soils are used mainly for grain crops, hay, and pasture. If tillage is excessive, the structure of the plow layer tends to break down and a cloddy seedbed results. Fall plowing is not a good practice, because further serious erosion is likely to take place. Practices are needed that help to control erosion if these soils are used for crops. "V^Hiere contour tillage and terraces are used, a suitable cropping system is one in which the soils are kept in mea- dow three-fifths of the time. If no practices are used that help to control ei'osion, a suitable cropping system consists of growing meadow crops most of the time and a small grain only occasionally. (Management group IIIe-3, woodland group 7) O'Fallon Series The O'Fallon series consists of moderately well drained, dark-colored, gently sloping soils that are moderately deep over a fragipan. These soils are on uplands, where they have developed in loess imder the influence of prairie vege- tation, or possibly mixed prairie and forest vegetation. They are on ridges and low knolls in the central and south- ern parts of the county. In most places the surface layer is about 12 inches thick and consists of very dark grayish-brown silt loam that has granular structure and is slightly acid to neutral. It is miderlain by a layer of heavy silt loam, about 3 inches thick, that has granular and subangular blocky structure and is very strongly acid. The upper part of the subsoil is about 10 inches thick and consists of yellowish-brown light silty clay loam. It has subangular blocky structure and is very strongly acid. The lower part of the subsoil, about 19 inches thick, is brown or dark yellowish-brown silty clay loam that is mottled with grayish brown or brown, has blocky or prismatic structure, and is very strongly acid. The imderlying material is gray to light-gray heavy silt loam to light silty clay loam that is massive, is very fiiTU when moist, and is brittle when dry. This material is very strongly acid. The lower part of the subsoil and the underlying ma- terial constitute a fragipan that restricts permeability and limits the depth to which roots extend. Consequently, these soils are moderately permeable in the upper part and only slowly permeable in the lower part. They have moderate available moisture capacity, are medivun in content of or- ganic matter, nitrogen, and potassium, and are low in con- tent of phosphorus. Except where the plow layer has re- ceived lime, these soils are strongly acid throughout the profile. Representative profile of one O'Fallon silt loam (1,700 feet west of the SE. corner of sec. 33, T. 9 N., R. 3 W., and immediately north of the road right-of-way) : Al — to 12 inches, very dark grayish-brown (lOYR 3/2) silt loam ; moderate, fine, granular structure ; friable when moist, slightly sticky and slightly plastic when wet ; slightly acid to neutral ; gradual, smooth boundary. AB — 12 to 15 inches, dark-brown (lOYR 3/3) heavy silt loam; many, fine, faint, dark yellowish-browu (lOYR 4/4) mottles ; strong, medium, granular and subangular blocky structure ; friable when moist, sticky and plas- tic when wet ; very strongly acid ; clear, smooth boundary. B2t — 15 to 25 inches, yellowish-brown (lOYR 5/4) light silty clay loam ; common, fine, distinct mottles of dark brown to brown {7.5YR4/4) or grayish brown (lOYR 5/2) ; moderate, medium, subangular blocky struc- ture; light-gray (lOYR 7/1) silt coatings over 10 per- cent of the exterior of the striictural aggregates ; firm when moist, sticky and plastic when wet; very strongly acid ; clear, smooth boundary. A'2&B't — 25 to 31 inches, brown to dark-brown (7.5YR 4/4) silty clay loam ; strong, medium, prismatic structure breaking to moderate, medium, angular blocky struc- ture in the lower part ; structural aggregates covered with light-gray (lOYR 6/1) silt grains, which give the horizon a distinct light-gray appearance; continu- ous, grayish-brown (lOYR 5/2) clay films that tend to be much thicker on the vertical faces of the aggre- gates than on the horizontal faces ; very firm when moist, sticky and plastic when wet ; very strongly acid; gradual, smooth boundary. B'xl— 31 to 38 inches, dark yellowish-brown (lOYR 4/4) silty clay loam ; common, fine, distinct, grayish-brown (lOYR 5/2) mottles; moderate, coarse, prismatic structure breaking to moderate, medium, angular blocky stinicture; dark grayish-brown (lOYR 4/2) clay films on the aggi-egates; very firm when moist, sticky and plastic when wet; very strongly acid; gradual, smooth boundary. B'x2 — 38 to 44 inches, grayish-brown (lOYR 5/2) silty clay loam ; many, medium, prominent, brown to dark- brown (7.5YR 4/4) mottles; weak, coarse, prismatic structui"e ; very fii"m when moist, very sticky and very plastic when wet ; when dry. has a few patches of light gi-ay (lOYR 7/1); very strongly acid; clear, smooth boundary. 34 SOIL SURVEY Cx — 44 to 50 inches, gray to light-gray (lOYR 6/1) heavy silt loam to light silty clay loam ; many, coarse, promi- nent, yellowish-brown (lOYR 5/4) mottles; massive; vei-y firm when moist, brittle when dry, sticlvy and plastic when wet; very strongly acid. O'Fallon soils occur with Oconee and Hosmer soils. They are better drained than the Oconee soils and are darker colored than the Hosmer. O'Fallon silt loam, 2 to 4 percent slopes (l 14B). — This is the only O'Fallon soil mapped in JNIontgomery County. It is generally on low ridges or ridge points, at a higher elevation than the surrounding soils. Its i)rofile is the one described for the O'Fallon series. Included with it in map- ping were small areas in which the surface layer is thin, and other small areas in which the slopes are as steep as 6 percent. This O'Fallon soil is less well suited to the crops com- monly grown in the county than ai"e most of the other dark-colored soils. Controlling erosion and applying the proper kinds and amounts of fertilizer are important management practices. If contour tillage or terracing is practiced, a cropping system in which this soil is used for meadow one- fourth of the time helps to control erosion. Where rotation of crops is the only means used to control erosion, a cropping system in which this soil is used for meadow one-half of the time is necessary. Managing crop residue well and keeping tillage to a minimum are other desirable practices. (Management group IIe-3, woodland group 2) Pana Series Deep, dark-colored soils that are well drained and are sloping to strongly rolling are in the Pana series. These soils are on the higher jDarts of morainal ridges in the cen- tral and eastern parts of the county. In most places the surface layer is about 8 inches thick and consists of very dark brown to very dark grayish- bi'own silt loam. It has granular to subangular blocky structure and is strongly acid. Beneath the surface layer is a layer, about 4 inches thick, of very dark brown to very dark grayish-brown heavy silt loam that has subangular blocky structure and is strongly acid. The subsoil is about 49 inches thick and consists of dark-brown or reddish- brown gravelly clay loam to loam that has subangular blocky sti-ucture and is strongly acid. Beneath the sub- soil is reddish-brown, strongly acid gravelly loam that, in turn, is underlain by stratified gravel and sand (fig 9). Pana soils have moderately rapid permeability but mod- erate available moisture capacity. They are medium to high in content of organic matter and nitrogen, and low in content of phosphorus and potassiiun. Except in areas where the p\oyv layer has received lime, tliey are strongly acid. If these soils are to be cropped regularly, practices are needed that help to control erosion. Representative profile of a Pana silt loam (320 feet south and 50 feet west of the NE. corner of sec. 3, T. 10 N., R. 1 W.) : Al — to 8 inches, very dark brown (lOYR 2/2) to very dark grayish-brown (lOYR 3/2) silt loam; moderate, me- diiun, granular to moderate, flue, subangular blocky structure ; friable ; few rounded pebbles ; strongly acid ; clear, irregular boimdary. AB — 8 to 12 inches, very dark brown (lOYR 2/2) to very dark grayish-brown (lOYR 3/2) gritty heavy silt loam; common, fine, distinct, brown ('7.5YR 4/4) mottles ^ftm mMi wmmm ^^ 1 1 ' '.■.>^" *r.* .» %* -- ', -C"' -, > -->"-\' ' " -I ■ '■ •ottom-land hardwoods. In most places the surface layer is about 17 inches thick and consists of very dark grayish-brown, dark-brown, and black loam. It has granular or subangular blocky struc- ture and is slightly acid to neutral in reaction. The subsoil, about 31 inches thick, is dark-brown heavy loam or loam (hat has subangular blocky structure and is slightly acid to neutral in reaction. The underlying material is dark- brown to brown loam that is massive and is slightly acid to neutral in reaction. Terril soils are moderately permeable and have high available moisture capacity. They are medium in content of organic matter, nitrogen, phosphorus, and potassium, and are medium acid to mildly alkaline in reaction. Representative profile of a Terril loam (540 feet east along center of road and 210 feet north of county highway bridge over Middle Fork Shoal Creek, in NEIO, NW40, I NE160, sec. 15, T. 8 N., E. 4 W.) : All — to 10 inches, very dark grayish-brown (lOYR .3/2) loam ; weak, fine, granular structure : friable ; iSlightly acid to neutral ; clear, smooth boundary. A12— 10 to 1.3 inches, black (lOYR 2/1) loam; moderate, fine, sul)angular blocky structure ; friable ; slightly acid to neutral ; gradual, smooth boundary. A3 — 13 to 17 inches, dark-brown (lOYR 3/3) loam: moderate, fine, subangular blocky structure; slightly acid to neutral ; gradual, smooth boundary. MONTGOMERY COUNTY, ILLINOIS 43 B21— 17 to 30 inches, dark-brown (lOYR 3/3) heavy loam; moderate, medium, subanguhir blocky structure; dis- continuous, thin, black (lOYR 2/2) coatings of organic matter are on the peds and line the many small to medium-sized pores ; firm ; slightly acid to neutral ; gradual, smooth boundary. B22 — 30 to 42 inches, dark-brown (lOYR 3/3) loam; weak to moderate, medium to coarse, subangular blocky struc- ture ; discontinuous, very dark grayish-brown (lOYR 3/2) coatings of organic matter are on the peds and line the pores ; firm to friable ; slightly acid to neutral ; gradual, smooth boundary. B3^2 to 48 inches, brown to dark-brown (lOYR 4/3) loam; weak to coarse, subangular blocky structure ; few, very dark grayish-brown (lOYR 3/2) coatings of organic matter are on the peds and line the pores ; friable ; slightly acid to neutral ; gradual, smooth boundary. C — 48 to 60 inches, dark-brown to brown (7.5YR 4/4) loam; massive ; friable ; slightly acid to neutral. In most places the texture of the solum is loam, but it ap- proaches fine sandy loam or silt loam. In many places small pebbles are scattered throughout the profile. Terril soils are better drained than Nokomis soils. They are darker colored than Camden soils. Terril loam, 2 to 5 percent slopes (587B). — This is the only Terril soil mapped in INIont^'omery County. Its pro- file is the one described for the Terril series. This soil is gently sloping and is on alluvial fans and stream terraces, at a slightly higher elevation than the soils on bottom lands. Ordinarily, flooding is not a hazard, but there are severe floods that do not last long. The dominant slopes are about 4 percent, but the slopes are as much as 7 percent in some areas. The average length of slopes is about 150 feet. Included with this soil in mapping were some areas in which stratified sand and silt are in the lower part of the profile. This Terril soil is suited to field crops, hay, and pasture, and it is also suitable for trees. Most of the acreage is in corn and soybeans. The soil is moderately well suited or well suited to the crops commonly grown in the county. Proper fertilization and good management are needed, however, and in places diversion ditches are also needed. They keep rimoft' from higher lying soils from spreading out over this soil and causing damage. Though this soil has gentle slopes, erosion is not a serious hazard. Contour tillage and terracing make runoff slow enough so that corn can be grown year after year without causing serious erosion. If contour tillage is practiced, using this soil for wheat or oats and growing a catch crop every fourth year will help to control erosion. (Manage- ment grouj? IIe-1, woodland group 7) Velma Series In the Velma series are loamy, dark-colored, moderately well drained soils that have developed in glacial till under prairie or mixed prairie and forest vegetation. These soils are sloping to strongly rolling. They occur along the edges of small valleys that have been formed by headwater ero- sion and entrenchment of streams. In most places the surface layer is about 14 inches thick and consists of very dark brown loam. It has granular structure and is strongly acid to medium acid. Beneath the surface layer is a layer, about 4 inches thick, of very dark brown and dark yellowish-brown heavy loam that has subangular bloclcy structure and is medium acid. The subsoil, about 28 inches thick, is dark-brown to gray clay loam that has subangular blocky and blocky structure and is strongly acid to slightly acid. The underlying material is gray clay loam that is massive and is neutral in reaction. Included with these .soils in mapping, especially on the upper parts of the slopes, are small areas of silty soils that developed in loess rather than in glacial till. In general, permeability is moderate, but it is slow in some severely eroded areas. The available moisture capaci- ty is moderate to high. The content of organic matter, ni- trogen, and potassium is medium, and the content of plios- phorus is low. Erosion is a serious hazard and is especially harmful because it makes these soils less suitable for crops. Except where the plow layer has received lime, the reac- tion is medium acid to strongly acid. Representative profile of a Velma loam (along west right-of-way of road, 444 feet south of the NE. corner, SE40, NE160, sec. 20, T. 10 N., R. 4 W.) : Al — to 14 inches, very dark brown (lOYR 2/2) loam ; strong, fine and medium, granular structure ; friable ; strong- ly acid to medium acid ; clear, smooth boundary. A3 — 14 to 18 inches, very dark brown (lOYR 2/2) and dark yellowish-brown (lOYR 4/4) heavy loam; moderate fine and medium, subangular blocky structure ; fri- able ; medium acid ; clear, smooth boundary. B21t — 18 to 24 inches, brown to dark-brown (lOYR 4/3) light clay loam ; many, fine, faint, very dark grayish-brown (lOYR 3/2) mottles; moderate, medium, subangular blocky structure, with dark grayish-brown (lOYR 4/2) coatings on the peds; friable; medium acid. B22t— 24 to 36 inches, brown (lOYR 5/3) clay loam; many, fine, prominent, brown to dark-brown (7.5YR 4/4) mottles and a few, fine, prominent, dark reddish- brown (5YR 3/2) mottles; moderate, medium and coarse, subangular blocky structure, with clay coat- ings on the peds ; black iron concretions ; strongly acid to medium acid ; gradual, smooth boundary. B3t — 36 to 46 inches, gray (lOYR 5/1) clay loam; many, me- dium, prominent, yellowish-brown (lOYR 5/6) mot- tles ; weak, coarse, angular blocky structure ; firm ; mediimi acid to slightly acid ; clear, smooth boundary. C — 46 to 70 inches, gray (lOYR 5/1) clay loam ; many, medium, prominent, yellowish-brown (lOYR 5/6) mottles; massive ; firm ; neutral. In many areas the Al horizon is very dark grayish-brown (lOYR 3/2). The combined thickness of the A horizons ranges from 7 to 18 inches. Velma soils have a darker colored surface layer than Hick- ory soils and lack the subsurface layer that is characteristic of Hickory soils. They are more deeply leached than the Hennepin soils. Unlike the Harrison soils, the Velma soils have developed in glacial till. Velma loam, 4 to 7 percent slopes (250C).— This sloping soil is in areas adjacent to drainageways. In general, its profile is similar to the one described for the series, but the surface layer ranges from 7 to 18 inches in thickness. This soil is well suited to the crops commonly grown in the county, but proper fertilization is needed. Erosion con- trol practices, such as terracing and contour tillage, are necessary if cultivated crops are grown. Where tho.se prac- tices are used, a cropping system in which meadow crops are grown 2 years out of 5 is suitable. If no practices are used to protect this soil, a row crop can be grown only oc- casionally without losses from erosion. (Management group IIe-2, woodland group 7) Velma loam, 4 to 7 percent slopes, eroded (250C2).— This sloping soil generally occurs in areas adjacent to drainageways. Its surface layer is thinner than the one in the profile described for the series. The plow layer is very dark grayish-brown loam but has a few lumps of material from the subsoil mixed into it. 44 SOIL SURVEY Incliuled with this soil in mapping were a few areas in \\ hicii the plow layer consists mainly of material from the subsoil. Those areas were too small to be shown separately on the soil map. This Velma soil is moderately well sviited or well suited to the crops commonly grown in the county, but proper fer- tilization is needed. Cultivated crops can be grown, but sucli practices as contour tiHage and terracing are needed. Where those practices are used, growing meadow crops 2 years out of 5 helps to protect this soil. If no erosion control practices are used, a row crop should be grown only occasionally. (Management group IIe-2, woodland group 7) Velma loam, 7 to 12 percent slopes (250D). — This is a rolling soil in areas adjacent to the large drainageways. It has a profile similar to the one described for the series, ex- cept that the surface layer is 7 to 14 inches thick. This soil is suited to the crops commonly grown in the comity. Pi'oper fertilization and practices that control erosion are needed, however, if cultivated crops are grown. If contour tillage is practiced, and if this soil is terraced, a cropping system in which meadow crops are grown two- tliirds of the time is necessary for controlling erosion. If no erosion control practices are used, this soil is suited pri- marily to pasture and hay. (Management group IIIe-1, woodland group 7) Velma loam, 7 to 12 percent slopes, eroded (250D2). — The surface layer of this soil is thimier than the one in the profile described as representative for the series. This is a rolling soil, adjacent to large drainageways. The plow layer is very dark grayish-brown loam that has a few lumps of subsoil mixed into it. In some ai'eas too small to be shown on the map, the plow layer consists principally of material from the subsoil. Included with this soil in mapping was a small area of a soil southeast of Hillsboro that is underlain by very clayey glacial deposits. This included soil has slopes of 7 to 12 percent. This Velma soil is suited to a row crop grown occasion- ally if terraces, contour tillage, and similar erosion control practices are used. It is suitable for pasture or hay, but good fertilization practices are needed. (Management group IIIe-1, woodland group 7) Velma loam, 12 to 18 percent slopes (250E). — This soil is in areas adjacent to large drainageways. It is rolling to moderately steep. The surface layer ranges from 7 to 14 inches in thickness. Tliis soil is suited mainly to hay crops, pasture, or trees. Its strong slopes and susceptibility to erosion make it un- suitable for row crops. (Management group IVe-1, wood- land groui) 7) Velma-Walshville complex, 4 to 7 percent slopes, eroded (996C2). — This soil complex is adjacent to drain- ageways. It is in the upper parts of the valleys of small streams in the central and southern parts of the county. The soils occur in such an intricate pattern that it was not feasible to show them separately on the soil map. They liave developed under a cover of mixed forest and grasses. Originally, these soils had a loamy, dark colored or mod- erately dark colored surface layer. Erosion has removed part of the original surface layer, however, and has left a surface layer that is lighter colored than the original one. The surface layer of the Walshville soil is somewhat lighter colored than that of the Velma soil. In many places after a heavy rain, the Walsliville soil in a recently plowed field can be disting-uished from the Velma soil by the lighter color of its surface layer. In many areas these two soils are of about equal extent, but the Velma soil is more extensive than the Walshville in some places. The extent of each varies considerably, however, within any one area. The profile of the Velma soil is like the one described for the Velma series. A detailed profile of the Walshville soil is described under the Walshville series. Included with these soils in mapping were small areas of soil that is fuier textured and more poorly drained than these soils and that has a profile superimposed on an older profile. The older profile is that of a soil that formed under different conditions than those active at the present time. Because erosion has removed much of the porous sur- face layer, less water enters these soils and more water runs off than in areas that are not eroded. In most places the Walshville soil is severely eroded but the Velma soil still retains part of its dark-colored surface layer. The Walsh- ville soil is less well suited to crops than the Velma. In some areas, particularly in areas where the Walshville soil is especially eroded, these soils do not support plant growth of any consequence. Even where the soils are prop- erly fertilized and have received the best management feas- ible, they are only poorly suited to the crops commonly grown in the county. Its alkaline subsoil makes the Walsh- ville soil more difficult to fertilize properly than the ad- jacent Velma soil. Consequently, crops growing on the Walshville soil often show deficiencies in plant nutrients that are not apparent on the Velma soil. Also, the Velma soil has higher available moisture capacity than the AValsh- ville because roots can penetrate to a greater depth. The slopes are short, and as a result, erosion control prac- tices are difficult to apply. "VVliere such practices as terrac- ing and contour tillage are used, however, a row crop can be grown occasionally. Even so, these soils are not well suited to row crops, because they have only a small supply of plant nutrients, have reduced available moisture capac- ity, and are harder to work than soils that are not eroded. (Management group IIIe-3, woodland group 7) Velma-Walshville complex, 7 to 12 percent slopes, eroded (996D2). — This is a rolling soil adjacent to drainage- ways where erosion has been active. In small areas, mainly of the Walshville soil, all of the surface layer has been re- mo^'ed and the subsoil is exposed. Most of the slopes are short. The dominant slope is about 10 percent. The Velma soil of this complex is less well drained than the typical Velma soils. In both the soils, the rate of in- filtration is slower, the amount of runoff is greater, and the supply of plant nutrients is smaller than in less eroded Velma and Walshville soils. Also, the available moisture capacity is lower than in the less eroded soils because erosion has removed most of the fertile, porous surface layer. Even though these soils are properly fertilized and are well managed, they are only moderately well suited to the crops commonly grown in the county. They are suitable for pasture and hay crops and are used mainly for those purposes, but they can also be used for wildlife and rec- reation. Row crops do not grow well and trees grow poorly, because of the alkaline subsoil of the Walshville soil. Prac- tices are needed that provide protection from further ero- sion. (Management group IIIe-1, woodland group 7) MONTGOMERY COUNTY, ILLINOIS 45 Virden Series Deep, daik-colorecl soils that are nearly level and are poorly drained are in the Virden series. These soils are in broad swales, mainly in the northern part of the county. In most places the surface layer is about 11 inches thick ;uid consists of black silty clay loam that has granular structure and is slightly acid to mildly alkaline. Beneath : the surface layer is a layer of black silty clay loam that is about 3 inches thick, has subangular blocky structure, ' and is neutral in reaction. The subsoil, about 39 inches thick, is very dark gray to grayish-brown and dark gray silty clay loam that has prismatic or blocky structure and I is lieutral to mildly alkaline in reaction. The underlying- material is gray silt loam that is massive and is mildly alkaline. ! Virden soils are naturally fertile and have liigh avail- \ able moisture capacity. They are high in content of or- ganic matter and nitrogen and medium in content of phos- phorus and potassium. These soils are neutral in reaction and have moderately slow pei'meability. The silty clay loam in their surface layer makes them more difficult to till than associated Harrison and Herrick soils that have a surface layer of silt loam. If soil tilth deteriorates, grasses and legumes need to be included in the cropping system : to help improve tilth. Eepresentative profile of Virden silty clay loam (100 feet north and 100 feet west of the SE. corner of sec. 11, T. 10 N., R. 5 W.) : Al— to 11 inches, black (lOYR 2/1) silty clay loam; mod- erate, fine to medium, granular structiu-e; firm when moist, very sticky and very plastic when wet; mildly alkaline ; gradual, smooth boundary. A3— 11 to 14 inches, black (lOYR 2/1) silty clay loam; mod- erate, fine, subangular blocky structure; firm when moist, very sticky and very plastic when wet ; neutral ; gradual, smooth boundary. Big— 14 to 19 inches, very dark gray (lOYR 3/1) silty clay loam; few, fine, distinct, gray (.5Y 5/1) mottles; mod- erate, medium, blocky structure ; firm when moist, very sticky and very plastic when wet ; neutral ; grad- ual, smooth boundary. B21g — 19 to 2(> inches, gray (5Y 5/1) silty clay loam; many, fine, distinct, very dark gray (lOYR 3/1) mottles; moderate, medium and fine, prismatic structure break- ing to moderate, medium, blocky structure ; contin- uous, very dark gray (lOYR 3/1) coatings on the peds ; firm when moist, very sticky and very jjlastic when wet ; neutral ; gradual, smooth boundary. B22g— 26 to 39 inches, grayish-brown (2.5Y 5/2) silty clay loam; many, fine, distinct, olive-brown (2.5Y 4/4) mottles ; weak, coarse, prismatic structure ; continu- ous, very dark gray (lOYR 3/1) coatings on the peds and many root tracks on the clay films ; firm when moist, very sticky and very plastic when wet; neu- tral ; diffuse, smooth boundary. B3g — 39 to 53 inches, dark-gray (N 4/0) light silty clay loam ; many, coarse, prominent, yellowish-brown (lOYR 5/4 to 5/8) mottles; continuous, very dark gray (lOYR 3/1) coatings on the peds; firm when moist, sticky and very plastic when wet ; many fine pores lined with very dark gray (lOYR 3/1) ; mildly alkaline; diffuse, smooth boundary. Cg — 53 to 60 inches, gray (N 5/0) silt loam; many, coarse, prominent yellowish-brown (lOYR 5/4 to 5/8) mot- tles ; massive ; friable ; many fine pores lined with very dark gray (lOYR 3/1) ; mildly alkaline. Virden soils occur with Herrick soils and Harrison soils but are more poorly drained than those soils. Also, they are finer textured than those soils and lack the A2 horizon that is typical in the profile of the Herrick soils. Virden silty clay loam (0 to 2 percent slopes) (50). — This is the only Virden soil mapped in Montgomery County. It has the profile described for the series. Included in mapping were small areas of a soil that has a surface layer of heavy silt loam, and other areas of a soil that con- tains concretions of calcium cai'bonate that are mainly in the subsoil. Drainage of this Virden soil has been improved by con- .structing drainage ditches and installing tile drains. Now, most areas are no wetter than areas of naturally better drained soils. The tile drains must be maintained, and sometimes they must be replaced to keep these soils ade- quately drained. Excejit in a few areas, this soil can be worked and crops can be planted as soon after rainy seasons as on better drained soils. Nearly all of the acreage is in corn, soybeans, and wheat, and this soil is well suited to those crops. It is usually plowed in fall, which permits the large clods to break down into a good seedbed before planting time in spring. (Management group IIw-1, wood- land group 7) Walshville Series In the Walshville series are moderately deep, medium- textux'ed, light-colored soils that are moderately well drained. These soils have developed in glacial till under a cover of mixed prairie and forest. They are characterized by a brown, acid upper subsoil and a gray lower subsoil that is alkaline in reaction, is high in exchangeable sodium, and restricts the development of roots. These soils are slop- ing to rolling and are adjacent to streams that are cutting into the uplands. They occupy small, scattered areas within larger areas of Velma soils. In most places the surface layer is about 11 inches thick and consists of very dark grayish-brown silt loam that has granular structure and is strongly acid. The subsurface layer, about 3 inches thick, is mottled dark grayish-brown heavy silt loam that has subangular blocky structure and is strongly acid. To a depth of about 21 inches, the subsoil is dark-brown to brown heavy clay loam to silty clay loam that has blocky structure and is strongly acid. Below that depth, to a depth of about 46 inches, the subsoil is grayish- brown to gray clay loam that has blocky structure or is massive and is moderately alkaline. Beneath is gray to light-gray calcareous heavy loam. Walshville soils have slow to very slow permeability and low available moisture capacity. Roots can penetrate their subsoil to only a limited depth. Representative profile of a Walshville silt loam (180 feet north and 45 feet east of the SW. corner of N^VIGO, sec.33,T.10N.,R.5W.): Al — to 11 inches, very dark grayish-brown (lOYR 3/2) heavy silt loam ; weak, medium, granular structure ; firm to friable ; strongly acid ; abrupt, irregular boundary. A2 — 11 to 14 inches, dark grayish-brown (lOYR 4/2) gritty, heavy silt loam ; many, distinct, very dark grayish- brown (lOYR 3/2) mottles; weak, very fine, subangu- lar blocky structure ; friable ; strongly acid ; abrupt, smooth boundary. B21 — 14 to 21 inches, dark-brown to brown (7.5YR4/4) heavy clay loam to silty chiy loam ; moderate, very fine and fine, blocky structure ; firm ; peds coated with reddish- brown (5YR4/4) and dark grayish-brown (10YR4/2) clay films; strongly acid: clear, smooth boundary. B22 — 21 to 30 inches, grayish-brown ( lOYR 5/2) heavy clay loam ; weak, coarse, blocky structure ; firm ; dark yel- lowish-brown (lOYR 4/4) clay films on the surfaces of 46 SOIL SURVEY some peds ; moderately alkaline ; gradual, smooth boundary. B31 — 30 to 46 inches, mixed gray (N 5/0) , strong-brown (7.5YR 5/6 to 5/8), and some dark yellowish-brown (lOYR 4/4) light clay loam; massive; friable; brown (7. SYR 5/2) clay films in the few cracks ; lime concretions in the lower part ; moderately alkaline ; diffuse, smooth boundary. B32 — 46 to 80 inches, gray to light-gray (N 6/0) heavy loam; many, coarse, prominent, strong-brown (7.5YR 5/6 to 5/8) mottles ; brown (7.5YR 5/2) clay films in the few widely scattered joint planes ; calcareous. The surface layer of a typical Walshville soil contains enough sand to give it a gritty feel. The thickness of the various hori- zons varies consideribly. In some areas the acid material above the alkaline part of the B horizons is 30 to 36 inches thick. Many areas are so eroded that the brown upper B hori- zons have been exposed, and material from those horizons is incorporated in the plow layer. In other areas the alkaline lower B horizons are exposed. The Walshville soils are intermingled with areas of Velma soils in such an intricate pattern that it was not feasible to show these soils separately on the soil map. Therefore, they were mapped together as a soil complex. The Walshville soils are similar to Tamalco soils but have developed in glacial till instead of in loess. Also, they have sandy and gravelly material throughout their profile that is lacking in the Tamalco soils. Weir Series In the Weir series are nearly level, light-colored, poorly drained soils that have develoj)ed in loess. These soils are in the part of the county that was originally under forest. Their original cover was a hardwood forest consisting of hickory and post oaks, blaclcjack oaks, and other kinds of oaks. In most places the surface layer is about 8 inches thick and consists of dark grayish-brown silt loam that has granular structure and is slightly acid. The upper subsur- face layer is about 4 inches thick and consists of gray silt loam that has platy structure and is strongly acid. The lower one is about 3 inches thick and consists of grayish- brown silt loam that also has platy structure but is very strongly acid to strongly acid. The subsoil, about 33 inches thick, is grayish-brown silty clay loam to silty clay that has blocky structure and is very strongly acid to slightly acid. The underlying material is gray to light-gray, massive silt loam that is medium acid to slightly acid. Weir soils are slowly permeable when wet and are very strongly acid in areas that ha^'e not been limed. Though they have moderate to high available moisture capacity, yields are Ioav in years when rainfull is limited. The con- tent of organic matter, nitrogen, phosphorous, and potas- sium is low. If these soils are tilled when dry, they are quickly pulverized into dust. After heavy rains, they rmi together readil}^, and replowmg is sometimes necessary to prepare a good seedbed. Representative profile of Weir silt loam (894 feet south- east along the east right-of-way of the road from the NW. corner of SE160, sec. 24, T. 9 N., R. 5 W.) : Ap^ — to 8 inches, dark grayish-brown (lOYR 4/2) silt loam; weak, fine, granular structure; friable; medium acid to slightly acid ; abrupt, smooth boundary. A21— 8 to 12 inches, gray (lOYR 5/1) silt loam that is light gray to gray (lOYR 6/1) when dry; moderate, thin, platy structure ; friable ; strongly acid ; clear, smooth boundary. A22— 12 to 15 inches, grayish-brown (lOYR 5/2) silt loam that is light gray (lOYR 7/1) when dry; moderate, thin, platy structure ; friable ; very strongly acid to strongly acid; abriipt, smooth boundary. B21t — 15 to 18 inches, grayish-brown (2.5Y 5/2) heavy silty clay loam; few, fine, prominent, strong-brown (7.5YR 5/8) mottles; moderate, fine, angular blocky struc- ture; has light-gray (lOYR 7/1) coatings on the struc- tural aggregates when dry and has light brownish- gray (lOYR 6/2) clay films on the structural aggregates ; firm ; very strongly acid ; gradual, smooth boundary. B22t— 18 to 40 inches, grayish-brown (2.5Y 5/2) silty clay; few, fine, prominent, strong-brown (7.5YR 5/8) mot- tles; weak to moderate, coarse, angular blocky struc- ture; firm; light brownish-gray (lOYR 0/2) clay films on the structural aggregates ; black iron concretions ; very strongly acid to strongly acid; gradual, smooth boundary. B3t — 40 to 48 inches, grayi.sh-brown (2.5Y 5/2) silty clay loam ; few, medium, prominent, dark-brown to brown (7. SYR 4/4) mottles; weak, coarse, angular blocky structure; firm; light brownish-gray (lOYR 6/2) clay films on the structural aggregates; mediiun acid to slightly acid ; gradual, smooth boundary. C — 48 to 60 inches, gray to light-gray (N 6/0) silt loam; coarse, prominent mottles ranging from brown or dark brown (7.5YR 4/4) to dark red (2.5YR 3/6) in color; massive ; friable ; medium acid to slightly acid. Weir silt loam (0 to 2 percent slopes) (165). — This soil has the profile described for the series. It is the only soil of the Weir series mapped in Montgomery County. Draining excess water from this soil is difficult. Ditches are needed if water tends to remain on the surface after heavy rains. Tile drains do not function properly, because of the slow i^ermeability of the siibsoil. Even where tliis soil has been drained, it usually remains so wet until late in spring that plants do not grow well. After plowing and the usual tillage have been com- l^leted, the plow layer tends to settle down in a compact mass that absorbs water only slowly. When the plow layer dries after a heavy rain, it is especially dense. Germinat- ing plants are unable to penetrate the mass to break through to the surface. For good germination and good yields, tillage should be limited to the minimum necessary for preparing the seedbed. This soil is better suited to wheat and soybeans than to corn. Alsike clover and ladino clover grown with tall fescue are well-suited meadow crops. Large amounts of fertilizer, frequently applied, are needed because of the low natural fertility. (Management group IIIw-1, wood- land group 4) Use and Management of Soils The soils of Montgomery County ;^re used mainly for cultivated crops and pasture. This section gives general information about managing the soils for these main pur- poses and also explains the capability classification used by the Soil Conservation Service to show the relative suita- bility of soils for various uses. It then groups the soils into management groups, gives facts about managing specific soils, and gives estimated yields under two levels of man- agement. Finally, it gives facts about managing the soils for trees and for engineering purposes. I MONTGOMERY COUNTY, ILLINOIS 47 General Management of Soils Used for Cultivated Crops Soils used for cultivated crops need management prac- tices that protect them from erosion, that remove excess water witliout causing damage, that maintain good tilth, and that maintain or increase the supplies of plant nutri- ents. These same j^ractices apply to all the soils in the county that ai'e used foi' corn, soybeans, wheat, oats, red clover, alfalfa, tall fescue, bluegrass, lespedeza, and other conmionly grown croj^s. Following is a brief discussion of these practices. More specific information about use and management of the soils is given under the appropriate management groups. G ontrolling erosion. — Erosion damages a soil and leaves it less productive, and it also damages roads, drainage ditches, and channels by depositing soil material washed from higher lying soils. Many of the soils in Montgomery County are subject to erosion if they are cropped, and if precautions are not taken to protect them. Where the soils are protected by a cover of i:)ermanent grass or trees, losses from erosion are usually negligible. Graded terraces are among the most effective means of controlling erosion in tilled fields, and many of them have been constructed. They are needed most on the long slopes of the Pike, Douglas, Harrison, Oconee, and Hoyleton soils because they intercept water and conduct it safely to a grassed waterway before it can cause erosion. Contour tillage is used with the terraces and is effective in control- ling erosion on the Douglas, Pana, Harrison, and other gently sloping or sloping, permeable soils. On strongly sloping soils, keeping the rows level is more difficult and tilling on the contour is less effective than on less sloping soils. On some sloping soils, stripcropping has been used to some extent, but its use is not widespread. A croi:)2)ing system that includes meadow crops provides an effective method of controlling erosion. While the close- growing meadow crop covers the soil, it reduces the amount of erosion that takes place and it also improves soil tilth. More water enters a soil that is in good tilth than enters a soil that is in poor tilth, and less water runs off to cause erosion. Keeping tillage to a minimum when preparing the seed- bed increases the infiltration of water and is another effec- tive means of reducing losses from erosion. Use of a herbi- cide often takes the place of several tillage operations, and it thus preserves the soil structure. Good management of crop I'esidue also protects the soils. Cornstalks shredded in fall, for example, provide the maxi- mum amount of protection. The hazard of erosion is serious where soils that are subject to erosion are plowed in fall and are left bare over winter. If fields are plowed in fall, a system for disposing of excess water should include the use of grassed water- Sfays, weir dams, and similar devices that will remove ex- 1 ess water without damaging the soils. Improving drainage. — Originally, many large areas of Virden, Harvel, and Shiloh soils, especially in the north- ern part of the county, wei-e so poorly drained that crops could not be grown on them. Since that time, 42 drainage districts have been organized and many ditches have been dug to supply drainage. Drainage of most of the poorly drained soils, as well as drainage of many soils in areas out- side those covered by the drainage districts, have been im- proved by installing tile drains. The soils that formerly were wet are now among the most productive of the soils in the county. In some places, however, additional drainage is needed. Tile drains and open ditches would increase the returns from soils in those areas. Tile drains do not draw satisfactorily in some of the slowly permeable soils, such as the Cowden, Weir, and Cisne, or in very slowly permeable soils, such as the Piasa and Huey. Shallow open ditches can be used to remove water that remains on the surface of those soils after heavy rains. Maintaining good tilth. — Maintaining good tilth is im- portant, especially in steej) soils that are farmed. Where a soil is in good tilth, more water enters it and less water runs off than where the tilth has deteriorated. If good tilth is maintained, erosion is less serious than where tilth has deteriorated, and more water is held available for crops. Good tilth is necessary for the firm, granular seedbed that is especially needed for alfalfa, grass, and other small-seeded crops. Excessive jilowing, disking, and harrowing tend to break down the tiltli of the surface layer, particularly in the Cowden, Cisne, Weir, and other soils that have a silty texture. Tillage 2)ractices that i-equire the least manipulation of the soil to make a suitable seed- bed are the most desirable and the most profitable. Meadow crops tend to cause aggregation of the soil particles, and thus they improve tilth. This is partly be- cause meadow crops require no tillage and partly because soil bacteria readily act to decompose the organic matter in residue from sod crops. In addition, crops that form a sod provide a protective cover and further reduce erosion. Maintaining fertility. — Soils of Montgomery County differ in reaction and fertility because of inherent differ- ences and past management. Therefore, the soils need to be tested to determine the pH value, or reaction, and the amount of phosphorus and potassium available in the plow layer. A representative of the County Extension Service or of the University of Illinois College of Agriculture can give assistance in taking soil samples and in interpreting the results of the tests. Tests to determine the amount of nitrogen ui the soils are not suitable for appraising the amount of nitrogen fertilizer needed for the growth of a specific crop through- out an entire growing season. This is because the content of nitrogen varies widely m soils within a short period of time, depending upon the temperature, the amount of moisture, the amomit of organic matter in the soil, and the kinds of plants growing on the soil. In many soils of Mont- gomery County, lack of nitrogen is the most limiting factor in obtaining good yields. Nitrogen should be added in commercial fertilizer, manure, legumes, and crop residue. General Management of Soils Used for Pasture About 17 percent of the total acreage in the county is used for pastures that are more or less permanent. Most of the pastures are on the rolling to very steep soils and on the adjacent small bottoms and ridgetops in areas of less sloping soils. The areas on tlie bottoms and ridgetops are generally so small and narrow that tilling them would not be profitable. 48 SOIL SURVEY The principal plants iised for pasture are bluegrass, tall fescue, and lespedeza, but weeds, brush, sedges, and other undesirable pasture plants are predominant in many places. The pastures are commonly grazed year after year for several decades without being properly fertilized and well managed. Consequently, the returns are low. Testing tlie soils and then applying plant nutrients or amendments suitable for alfalfa and clover is desirable. After that, a grass-legTime mixture should be seeded. Regular additions of lime, phosphorus, and potassium are necessary to keep the pastures productive, but eventually, the legumes die out. Then, it is necessary to renovate and reseed to legumes or to apply a nitrogen fertilizer annually to keep the grasses productive. Planning and managing a j^asture is more effective if the characteristics of the soils are considered. For example, the kinds of grasses and legumes seeded in a pasture of nearly level, productive soils that are to be grazed for only a short time may not be the most desii'able for seedmg on steej) soils of low pi'oductivity on which the pasture is to remain suitable for grazing for 4 or 5 years or as long as possible. Pasture rnanagement fo?' strongly sloping to steep soils. — The strongly sloping to steep Hickory, Negley, Hennepin, and Velma soils of management groups IVe-1, VIe-1, and VIIe-1 are the soils used most extensively for pasture. The steep slopes and small streams make difficult the tillage needed for seeding and applying fertilizer in many areas of these soils. In some places the soils are so steep that the same tools cannot be used for applying fer- tilizer and lime as are commonly used for applying fertili- zer and lime in ai'eas used for field crops. For this I'eason, pastures that will last for a long time should be estab- lished. Most areas of these soils are now covered with bluegrass, which makes a satisfactory cover but is less pro- ductive than tall fescue, orchardgrass, and bromegrass. Bromegrass may be less productive on these soils than on other soils, vxnless it is seeded as a companion crop with a legume or receives annual applications of nitrogen and other kinds of fertilizer. Common lespedeza, Korean lespedeza, white clover, and yellow trefoil are the legumes that most commonly appear without seeding on the Hickory soils and on similar soils used for pasture. Common lespedeza and Korean lespedeza are animals. They produce forage of good (juality for only a short period during July through September, and this short season makes the total annual yield of forage low. White clover is not a dependable legume on these soils. It often appears spontaneously after a wet period but tends to disappear during the dry months. These soils are not so well suited to alfalfa as are some other soils. The stand begins to thin out soon after the alfalfa is seeded, and it usually disappears within 5 or 6 years. Nevertheless, alfalfa is the most productive legiune for seeding on these soils. The best practice for seeding or reseeding a pasture on strongly sloping to steep soils, such as those of the Hick- oi"y, Negley, Hennepin, and Velma series, is to kill the sod in spring by plowing the less sloping areas and disking the steeper ones. Special equipment is needed to renovate areas where the slopes are steeper than 30 percent. Such areas should be disked after weeds and grasses appear, because disking allows moisture to accumulate in the soil. Enough lime should be applied to give the surface layer of the Hickory and Negley soils a pH value of 7, so that it will be about neutral in reaction. The Hennepin soils are neutral to alkaline and do not need additional applica- tions of lime. Needed phosphorus and potassium ought to be applied at the time of seeding. The cost of applying amendments is great enough, however, no matter what the size of the application, that applying a large amount of plant nutrients at one time is more economical than apply- ing a small amount frequently. August is the best time to seed pastures if enough mois- ture is available. On these soils alfalfa, mixed with tall fescue or orchardgrass, has proved to be the most suitable species for producing pasture for cattle. Renovating in strips reduces the hazard of erosion in steep areas or on long slopes. In the steep or bare areas that might erode, a light application of straw or a mulch of manure after seeding helps to control erosion and encourages the de- velopment of a good stand. Reseeded pastures need careful management to prolong the life of the alfalfa. Rotating the pasture helps to main- tain the stand. Alfalfa should not be pastured after the middle of September, because the plants need time to build up a reserve of plant nutrients for use during winter and the following spring. Potassium and phosphorus ought to be applied amiually if they are needed to maintain the supply of plant nutrients in these soils. After the stand is about .5 years old, several tons of lime are generally needed to maintain the neutral reaction of the surface layer. Keep- ing the stand in good condition is better than allowing it to deteriorate and then going through the costly process of renovating. After the legumes disappear, reseeding should usually be repeated. Nevertheless, if the stand of grass is good, and if reseeding is difficult, a nitrogen fertilizer can be applied annually instead of reseeding the areas, and a year's use of the land is not lost. The nitrogen fertilizer replaces legumes as a source of nitrogen and keeps the grasses highly productive. Pasture management for nearly level soils of hottorn lands. — In this group are the nearly level bottom-land soils of the Lawson, Colo, Radford, and Landes series, in management groups 1-3, IIw-1, and IIIs-1. In most places these soils occupy narrow strips, between areas of steep Hickory and Velma soils. These strips are divided into even smaller areas by meandering streams. Using large equipment to farm these small areas is difficult. Therefore, many of them are used for pasture. Most of these soils of bottom lands are fertile and have good moisture-supplying capacity. Because they occur in low areas, they are protected from drying winds, and they generally produce high yields of pasture. Flooding that lasts for a period of several hours to several days, however, is a hazard. These soils are well suited to ladino clover, and the Landes soil and areas of other soils that are not poorly drained and that are flooded for only short periods are also suited to alfalfa. Tall fescue and orchardgrass are the most desirable grasses for these soils, but bromegrass does well in the valleys of the smaller streams that do not over- flow or where flooding is of only a few hours' duration. The Colo soil, in the valleys of the larger streams, is suited to reed canarygrass and ladino clover. At times, that soil is flooded for periods lasting for several days. MONTGOMERY COUNTY, ILLINOIS 49 These soils are mostly about neutral in i-eaction, but tests are needed to determine the requirements for lime, phos- phoi'us, and potassium. Then, the proper kinds and amounts of fertilizer should be applied. Ladino clover and tall fescue can best be seeded in spring as soon as a good seedbed can be prepared. The pastures need to be managed so that the growth of ladino clover will be encouraged. They should be purposely undergrazed early in sj)ring when growth is most rapid. Deferring grazing not only permits the ladino clover to reseed naturally, but it also allows the plants to produce highly nutritious forage that will be ready later when growth of the j^lants is slower. Wliere ladino clover has produced seed, the pastures are usually restored by volunteer seed that has germinated. After a pasture is established, enough fertilizer needs to be applied to maintain a good stand and the growth of the pasture plants. A fertilizer high in content of phos- phorus and potassium increases the yields of legumes and makes them more able to compete with the grasses. Nitro- gen, on the other hand, increases the production of the grasses, and thus suppresses the growth of legumes in the mixture. Pasture management for nearly level or gently sloping^ sloxoly permeable soils. — This pasture management is ap- plicable to the Cowden, Cisne, Hoyleton, Oconee, Weir, and other nearly level or gently sloping, slowly permeable soils of management groups Ilw-ii, IIe-4, IIIw-1, IIIw-2, and IVw-1. These soils are not commonly used for pasture, but satisfactory yields of pasture are generally produced under good management. Alfalfa and ladino clover are the best long-time legumes for mixtures on these soils. For pastures that will be productive for a shorter time, alsike clover is suitable. The stand of alfalfa generally does not last long on the Weir soil, even though this soil is properly fertilized and well managed. Tall fescue is the best kind of grass to grow on the soils of this group, but the soils are also suited to orchardgrass, timothy, and redtop. Wliere a new pasture is to be seeded or on old pasture is to be reseeded, planting a row crop in the area 1 year before seeding the pasture mixture heljDS to eliminate most of the undesirable weeds, grasses, and perennial weeds. Oats can then be seeded and used for pasture, or develop- ment of the pasture can be delayed until summer. Seeding a pasture later in summer is usually most desirable, as these soils are slow to dry out and do not warm up until late in spring. Then, it is too late to obtain a good stand of the commonly grown pasture grasses. Pastures on these soils need about the same kind of management as that used for other pastures, except that care must be taken to keep live- stock from trampling the areas when the soils are wet. Pasture ma/nagement for nearly level to sloping., moder- ately permeable to slowly permeable soils. — This pasture management is applicable to the nearly level to sloping, moderately permeable to slowly permeable soils of the Herrick, Harrison, Douglas, Hosmer, and similar soils in management groups I-l, 1-2, IIe-1, IIe-2, IIe-3, IIIe-1, IIIe-2, and Ille-S. These soils are seldom used for pas- ture because they are highly desirable for row crops, but they are well suited to a number of perennial legumes that can be used for pasture, including alfalfa, ladino clover, and alsike clover. They are also suited to many kinds of grasses, for example bromegrass, tall fescue, orchardgrass, and timothy. No unusual problems are encountered in establishing or managing pasture on these soils. Seeding can be done either early in spring or late in summer, as desired. Applying the proper kinds and amounts of fertilizer is important. Lime, phosphorus, and potassium are needed for good stands of forage that will last for several years. Nitrogen is needed for grasses and for grass-legume mixtures where the leg- umes are dying out. Capability Groups of Soils Capability classification is the grouping of soils to show, in a general way, their suitability for most kinds of farm- ing. It is a practical classification based on limitations of the soils, the risk of damage when they are used, and the way they respond to treatment. The classification does not apply to most horticultural crops, or to rice and to other crops that have their special requirements. The soils are classified according to degi'ee and kind of permanent limitation, but without consideration of major and gen- erally expensive landf orming that would change the slope, depth, or other characteristics of the soils; and without consideration of possible but unlikely major reclamation projects. In the capability system, all kinds of soils are grouped at three levels, the capability class, subclass, and manage- ment group. These are discussed in the following paragraphs. Capability Classes, the broadest grouping, are desig- nated by Roman numerals I through VIII. The numerals indicate progressively greater limitations and narrower choices for practical use. The classes are defined as follows : Class I. Soils have few limitations that restrict their use. Class II. Soils have some limitations that reduce the choice of plants or require moderate conservation practices. Class III. Soils have severe limitations that reduce the choice of plants, require special conservation practices, or both. Class IV. Soils have very severe limitations that re- strict the choice of plants, require very careful management, or both. Class V. (None in Montgomery County) Soils sub- ject to little or no erosion but have other limita- tions, impractical to remove, that limit their use largely to pasture, range, woodland, or wildlife food and cover. Class VI. Soils have severe limitations that make them generally unsuited to cultivation and limit their use largely to pasture or range, woodland, or wildlife food and cover. Class VII. Soils have very severe limitations that make them unsuited to cultivation and that re- strict their use largely to grazing, woodland, or wildlife. Clas VIII. (None in Montgomeiy County) Soils and landf orms have limitations that preclude their use for commercial plant production and restrict their use to recreation, wildlife, or water supply, or to esthetic purposes. Capability Subclasses are soil groups within one class; they are designated by adding a small letter, e, w, s, or c, 50 SOIL SURVEY to the class numeral, for example lie. The letter e shows that the main limitation is risk of erosion unless close- growing plant cover is maintained; ro shows that water in or on the soil interferes with plant growth or cultivation (in some soils the wetness can be paitly corrected by arti- ficial drainage) ; s shows that the soil is limited mainly be- cause it is shallow, droughty, or stony ; and c, used in some parts of the United States, but not in Montgomery County, shows that the chief limitation is climate that is too cold or too dry. In class I there are no subclasses, because the soils of this class have few limitations. Class V (none in Montgom- ery County) can contain, at the most, only subclasses in- dicated by w, 5, and acted if these soils were flooded durmg winter or early in spring, and if water stood on them. MANAGEMENT GROUP IIc-1 Gently sloping Camden, Douglas, Harrison, Pike, Sicily, and Ten-il soils are in this management groxip. Most of these soils have a silty surface layer. The water table rarely rises to a height above 3 feet from the surface, and nor- mally it is below the depth to which roots penetrate. These soils are well drained or moderately well drained, are moderately permeable, and have higli available mois- MONTGOMERY COUNTY, ILLINOIS 51 Figure 10. — A field of nearly level Lawson silt loam of management group 1-3, with a sloping Hickory soil in the background. ture capacity. Their content of organic matter ranges fi-om low to high. All of these soils, except the Camden and Pike, have a medium content of phosphorus and potassium, and the Camden and Pike soils have a low content of those ele- ments. Surface runoff is medium and can cause erosion. The soils of this group are suited to many different crops and are used mainly for corn, soybeans, wheat, oats, red clover, and alfalfa. Terracing, fanning on the contour, rotating crops, managing crop residue projDerly, and keep- ing tillage to a minimum are i>ractices that are used to help conti'ol erosion. The cropping system needed to control erosion depends upon the other practices that are used. If the soils are not tei'raced or farmed on the contour, erosion can be con- ti-olled by using a cropping system in which grasses and legumes are grown for meadow 2 years owt of 5 or 1 year out of 3. Where terracing and contour farming are prac- ticed, these soils are suited to row crops and small grains grown year after year. These soils need to have the residue from corn and soy- beans left on the surface o\er winter. The residue provides a nudch that reduces the force of raindrops striking the soil, and it thereby helps to control erosion. Plowing in S2)ring is more desirable than plowing in fall, for the soils are likely to erode if they are plowed in fall. Leaving the surface as cloddy as possible while still breaking the clods enough to make a satisfactoiy seedbed improves the soil structure. Too much tillage breaks down the soil structure and causes excessi^'e runoff and erosion. Except on the Ter- ril and Camden soils, grassed waterways and small dams are needed in many places to i-emove runoff' without caus- ing erosion. The Terril and Camden soils are on alluvial fans and stream terraces where runoff' from the adjacent higher areas could cause erosion. Diversion ditches are needed in some places to protect those soils. MANAGEMENT GROUP IIe-2 In this management group are sloping Camden, Doug- las, Harrison, Pana, Pike, Sicily, and Velma soils that are slightly to moderately eroded. Most of these soils have a silty surface layer. Surface runoff is rapid, and further erosion is a hazard. All of these soils but the Pana and VeLma have high available moisture capacity, and those soils have moderate 52 SOIL SURVEY available moistui'e capacity. In the Camden and Pike soils, the content of organic matter is low; in the Douglas and Harrison soils, it is high; and in the rest of the soils it is medimn. The Pana and Velma soils are low in content of phosphorus and potassium, and the other soils are medium in content of those elements. The soils of this group are suited to corn, soybeans, wheat, red clover, alfalfa, and a number of other crops. Liberal amoimts of fertilizer are needed, however, to help produce fast-growing, healthy plants that will protect the soils from erosion, generally produce good yields, and add organic matter. If these soils are used for row crops, they should be ter- raced, farmed on the contour, or stripcropped. Crop resi- due, for example shredded cornstall-cs left on the surface m fall after the corn is harvested, helps to reduce losses from erosion. Wlien the seedbed is prepared, tillage needs to be kept to a minimmn, and only the row tilhage necessary to secure germination of the crop is advisable. Plowing in fall increases the hazard of erosion. Grassed waterways and small dams are needed to remove runoff safely without damaging the soils. Where those practices are not used to control erosion, the soils are suited primarily to meadow and pasture, though they can be used occasionally for a row crop. MANAGEMENT GROUP IIe-3 Gently sloping Hosmer and O'Fallon soils that have a silty surface layer are in this management group. These soils have a compact layer ( f ragipan ) in the lower part of the subsoil. They do not have a water table witliin the depth to which the roots of most crops penetrate. The f ragipan prevents water from draining through the lower part of the subsoil. Therefore, these soils are only mod- erately well drained, even though runoff is medium to rapid. The ujipcr part of the subsoil is moderately permea- ble, and the lower part, is very slowly permeable. Because the fragipan limits the depth to which roots penetrate, these soils are considered to be only moderately deep wliere they are used for farming. They ha\'e only moderate avail- able moisture capacity. These soils are subject to erosion if they are plowed and are not protected. They are very strongly acid throughout their profile. The Hosmer soil is low in content of phos- phorus, potassium, nitrogen, and organic matter. The O'Fallon soil is low in content of phosphorus and i^otas- simn, and medium in content of nitrogen and organic matter. These soils are less well suited to corn and soybeans than many of the other soils in the county because of their mod- erate available moisture capacity. They are better suited to wheat than to corn or soybeans because wheat grows in fall, winter, and spring when the supply of moisture is us- ally abundant. The soils are moderately well suited to alfalfa if they receive enough lime and fertilizer. Constructing terraces or growing meadow crops about 1 year out of 3 provides protection from erosion. If con- tour farming is practiced and tillage is kept to a minimum, row crops can be grown a greater part of the time in the cropping system and losses from erosion will still be kept low. Making the maxiinum use of crop residue and delay- ing plowing as long as feasible so that crop residue will be left on the surface helps to control erosioii. Grassed water- ways and dams are needed in many places to prevent run- off from causing g-iillying. MANAGEMENT GROUP lle-i In this management group are mainly gently sloping, light-colored and moderately dark colored Hoyleton, Oconee, Starks, and Stoy soils that have a silty surface layer and a slowly permeable subsoil. Some of these soils ai'e eroded to the extent that only the plow layer remains of the original surface layer. Because the subsoil is slowly permeable, much of the water runs off these soils and causes erosion. Also, drainage is somewhat poor because excess water that enters the surface soil does not drain down through the subsoil. As a result, the plow layer is too wet for planting and tillage for long periods after extensive rainfall in spring. The available moisture capacity is high. All of these soils are low in content of phosphorus. The Stoy and Starks soils are also low in content of organic matter and nitrogen, and the Oconee and Hoyleton soils are medium in content of organic matter and nitrogen. The Starks and Oconee soils have a medimn content of potas- sium, and the other soils are low in that element. The soils of this gi'oup are better suited to corn, soybeans, wheat, clover, and alfalfa than to most other crops com- monly grown. Oats are not usually grown, because the soils are generally too wet for planting until so late in spring that yields are low. Wetness also delays the planting of corn and soybeans until after the best dates for planting those crops. Consequently, yields of corn and soybeans are likely to be lower than those on more permeable soils. Large amounts of fertilizer are needed, and terraces are also needed if these soils are used for row crops. Where the only erosion control practice used is farming on the con- tour, a suitable cropping system is one in which meadow crops are grown about 1 year out of 4 or 2 years out of 5. If the soils are not farmed on the contour, a cropping sys- tem in which legumes or grasses are gi-own for meadow or pasture about 1 year out of 3 keeps losses from erosion to a minimum. MANAGEMENT GROUP IIw-1 In this management group are dark-colored, poorly drained soils of the Colo, Harvel, Shiloh, and Virden series. These soils are in depressions where the water table is high during wet seasons, unless it has been lowered by installing tile drains. During long dry periods in summer and fall, the water table is below the depth to which the roots of most crops penetrate. These soils have moderate or moderately slow jDermea- bility and high or very high available moisture capacity. They have a high content of organic matter and nitrogen and a medium to high content of phosphorus and potas- sium. Emioff is slow to medium, depending upon the effec- tiveness of the open ditches that have beeii constructed to improve drainage. If runoff is slow enough, water col- lects on the surface. Then, wetness delays the planting of crops or damages crops that are growing on these soils. The Colo soil is also subject to occasional flooding when streams overflow. Flooding usually occurs early in spring before coim, soybeans, or other row crops are planted. Corn and soybeans are the principal crops, but some red clover, alfalfa, and wheat are grown. The soils are well suited to these crops, but tile drains and open ditches are needed to provide drainage. Additional tile drains should be installed if these soils remain wet in spring after others in the area are dry enough for tillage. Even where drainage MONTGOMERY COUNTY, ILLINOIS 53 has been improved, a good seedbed is difficult to prepai'e because of tlie large amount of clay in the plow layer. Fall plowing is better than spring plowing because the hard clods tend to break down during winter after they have frozen and then thawed, and after they have become wet and then dried. Where the soils are not fall plowed, plow- ing them in spring as soon as they are diy enough for tillage helps in preparing a suitable seedbed. Intensive cropping to corn, soybeans, and other row crops can cause these soils to be in poor tilth. Tilth is improved by growing grasses and legumes occasionally. MANAGEMENT GROUP IIw-2 Nearly level to gently slopping soils of the Cowden, Ebbert, Hoyleton, Oconee, and Stoy series are in this capability unit. These soils have a silty surface layer and a fine textured or moderately fine textured subsoil. The color of the surface layer ranges from moderately dark in the Cowden soil to light in the Stoy. The Ebbert soil has moderately slow or slow perme- ability, and the other soils have slow i:)ermealiility. In the nearly level areas, water remains on the surface for long periods, miless ditches have been constructed to remove it (fig. 11) . In most places the Stoy, Oconee, and Hoyleton soils have enough slope so tliat most of the water drains off and drainage ditches are not needed. In the Ebbert soil, the water table is high during wet seasons, especially in spring. Even where ditches have been installed, these soils remain wet in spring, and crops cannot be planted until after the most favorable time for planting. The soils of this group are suited to corn, soybeans, wheat, clover, aiid alfalfa, and the}' are generally used for those crops. Oats are not generally grown, because in most seasons they cannot be sown until long after the most de- sirable time for planting. Yields are generally lower than on other nearly level soils. At least part of the time, the lower yields are caused by a delay in planting the crop in spring. Wheat grows well on these soils and formerly was the crop most commonly grown. Fertilizer and lime are needed. Flowing in fall is not a general practice, though erosion is not a hazard. Where the soils are plowed in fall, the Figure 11. — A wet spot in a field of Cowden silt loam showing the effects of poor drainage on corn. Wet areas such as this are typical in soils of management group IIw-2. plow layer becomes much too compact to make a good seedbed after the clods have been broken down during winter by freezing, thawing, and heavy rains. Excess water needs to be removed by installing ditches or grassed water- ways, depending upon tlie slope of the drainage channel. ExcejDt in the Ebbert soil, tile drains are not practical. In areas of the Ebbert soil that are adjacent to Virden soils, tile drains can be installed by spacing the laterals at close intervals so that an entire field can be drained. MANAGEMENT GROUP IIIc-1 In this management group are sloping and rolling soils that are slightly to seriously eroded. These soils are in the Blaii-, Douglas, Hickory, Pana, Pike, Velma, and Walsh- ville series. In none of these soils is wetness a serious haz- ard, though the Blair soil has colors that indicate some- what poor drainage. In most places runoff is rapid on these sloping soils. The content of organic matter and nitrogen is high in the Douglas soil, medimn in the Pana and Velma soils, and low in the other soils. The Douglas and Pike soils, which have developed in loess, have a moderate content of phosphorus and potassium, and the other soils, developed in glacial till, have a low content of those elements. All of the soils liave ail acid root zone. The Douglas and Pike soils have high available moisture capacity, and the other soils have moderate available moisture capacity. Permeability is moderately slow or slow in the Blair soil and moderate in the other soils. The soils of this group are suited to corn, soybeans, wheat, alfalfa, and pasture. The alfalfa is a high-value crop when grown with tall fescue and bromegrass for hay or pasture. Excessive soil erosion can result if corn, soy- beans, or other row crops are grown without using con- touring, terracing, or other practices that help to protect the soils. A well-planned water-disposal system, including grassed waterways, dams, and diversion ditches oi' diver- sion terraces, is needed. Also crop residue, left on the sur- face, provides cover, promotes the infiltration of water, and reduces losses from erosion. MANAGEMENT GROUP IIIe-2 In this management group are light-colored and moder- ately dark colored, sloping Hosmer and Oconee soils that are slightly eroded to moderately eroded. These soils have slowly permeable lower horizons, but drainage is not re- quired. Water runs off rapidly. Even so, many of these soils dry out slowly in spring. The unfavorable character- istics of the lower part of the subsoil make the available moisture capacity moderate. In the Oconee soil that is not eroded or that is only slightly eroded, the content of or- ganic matter and nitrogen is medium, and in the other soils, it is low. The content of phosphorus is generally low, and the content of potassium is medium. These soils are only moderately well suited to corn, soybeans, wheat, hay, and meadow crops if erosion con- trol practices and other good management practices are used. Growing row crops without farming on the contour or terracing is likely to cause losses from erosion. Even where the soils are farmed on the contour and terraced, growing corn or soybeans for 2 or more years in succession can cause excessive losses from erosion. In many places grassed wat-erways and erosion control dams are needed to carrj^ runoff away safely without causing gullying. 54 SOIL SURVEY MANAGEMENT GKOUP IIIe-3 111 this management group are Tamalco and Walshville soils that have an alkaline subsoil that contains excess ex- changeable sodium, and Hoyloton, Oconee, and Velma soils that have an acid subsoil. The Hoyleton and Oconee soils are intermingled Avitli Tamalco soils, and Velma soils are intermingled with the Walshville soils. The soils are gently sloping to sloping and have a light-colored to moderately dark colored, silty or loamy surface layer. Most of them are eroded to some extent. Because the subsoil is slowly permeable in most places, further erosion is a serious hazard, and it would make these soils less suitable for crops. Further erosion would be especially serious in the soils that have an alkaline subsoil and that have a high con- tent of sodium, in addition to having other undesirable characteristics. Runoff is generally rapid. Therefore, artificial drainage is not needed, except in small seepy areas. The content of organic matter, nitrogen, phosphorus, and potassium is low, and the available moisture capacity is moderate. The Tamalco soils are not well suited to crops, and further erosion would make them even less suitable. Ex- cept in years when the amount of moisture is favorable, the other soils are also not well suited to crops. The lim- ited available moisture capacity makes the soils better suited to wheat than to corn and soybeans. Large amounts of fertilizer are needed. Tlie soils of this group should be tilled only enough so that a good seedbed can bs prepared. Excessive tillage in- creases runoff and consequently causes soil erosion. Fall plowing exposes the soils to erosion over winter. Contour- ing, terracing, and similar erosion control practices pro- tect the soils if row crops are grown year after year. Where those practices are used, meadow and pasture crops grown 1 year out of 3, or 2 years out of 5, provide satisfactory con- trol of erosion. If those practices are not used, growing meadow crops almost continuously is necessary to reduce losses from erosion to a safe level. Small grains ordinarily are used Avlien a meadow crop is to be reseeded. MANAGEMENT GROUP IIIw-1 In this management group are nearly level or gently sloping, poorly drained Chauncey, Cisne, Racoon, and Weir soils that have a slowly permeable or very slowly per- meable subsoil. All of these soils have a silty surface layer. In general, the surface layer of the Chauncey, Cisne, and Racoon soils is moderately dark colored, and that of the Weir soil is light colored. Surface drainage is generally slow, and shallow ditches have been installed in many places to improve drainage. Water does not seep down through the profile when these soils become fully moist. As a result, the soils are often too wet for tillage until late in spring, and they are too wet for tillage in some years until summer. Corn and soybeans are likely to be damaged if the amount of rainfall is higher than average. Crops turn yellow from lack of nitrogen be- cause of denitrification that occurs in wet soils. The slow permeability keeps water from moving into the tile drains that have been installed. The Weir soil is low, and the other soils are low to medium, in content of organic matter and nitrogen. All the soils are low in content of phosphorus and potassium. These soils can be used for corn and soybeans, but they are more suitable for wheat. They are sometimes too wet for corn and soybeans to be planted and tilled at the proper time. Additional ditches are needed in some areas. In others the present ditches need deepening. Large applica- tions of lime, nitrogen, phosphorus, and potassium are needed. MANAGEMENT GROUP IIIw-2 In this management group are intermingled soils of the Cowden, Herrick, and Piasa series. These soils have a moderately dark colored or dark colored, silty surface layer, and they have a high water table late in winter and early in spring. The color of the Piasa surface layer is light enough that those soils can be easily distinguished in a field in which soils of this group occur. The lower part of the Piasa subsoil is alkaline, and those soils contain a large amount of sodium. The subsoil of the Cowden and Herrick soils is acid. The Piasa and Cowden soils are very slowly permeable, and the Herrick soil is moderately permeable. In the Piasa soils, the content of organic matter, nitrogen, phosphorus, and potassium is low, and in the Cowden soils, it is medium. In the Herrick soil, the content of organic matter and nitrogen is high and the content of phosphorus and potassium is medium. Dur- ing seasons of moderately dry weather, the growth of crops is limited by the shallow root zone of the Piasa soils, which reduces the supply of available moisture. The Cowden and Herrick soils have high available moisture capacity. Crops grown on those soils are affected only slightly by dry weather. The soils of this group are suited to corn, soybeans, wheat, alfalfa, and clover. The Piasa soils are less well suited to those crops, however, than the Herrick and Cow- den soils, liecause they often dry out so slowly in spring that planting time is long delayed. The Piasa soils are practically impermeable to water. Therefore, tile drains placed in those soils do not improve drainage. Also, tile drains do not improve drainage of the Cowden soils, be- cause that soil has a dense, compact subsoil. If water re- mains on the surface of the Piasa and Cowden soils after rains, shallow ditches should be dug to remove the excess water. Tile drains can be ])rofitably installed in the larger areas of Herrick soil, provided only small acreage of Piasa soils is intermingled with the areas of Herrick soil. The alkaline lower subsoil and high content of sodium make a supply of plant nutrients hard to maintain in the Piasa soils, for plants have difficulty utilizing the phos- ])horus and potassium in soils that are alkaline. They are able to use only the phosphorus and potassium in the less alkaline or slightly acid upper part of the profile, instead of having those plant nutrients available throughout the root zone, as in most soils. Consequently, a larger supply of phosphorus and potassium must be maintained in the plow layer to compensate for their restricted availability in the subsoil. Additional information about using and managing the Cowden soils can be found by referring to management group IIw-2. Additional information about using and managing the Herrick soil can be found by re- ferring to management group 1-2. MANAGEMENT GROUP IIIs-1 Landes fine sandy loam is the only soil in this manage- ment group. It is a sandy, dark-colored, nearly level soil that has formed in alluvium on flood plains. Drainage is somewhat poor, and the colors throughout the profile are MONTGOMERY COUNTY, ILLINOIS 55 typical of those of a somewliat poorly drained soil. Never- theless, the water table is high for only a few days each year. Flooding occui's occasionally. It is not a serious haz- ard, however, because this soil is at a somewhat higher elevation than the other soils of flood plains. The available moisture capacity is moderate to low. Therefore, yields are often limited by lack of adequate moisture in all but the most favorable years. The content of organic matter and nitrogen is medium, and the content of phosphorus and po- tassium is low. The reaction is slightly acid to neutral. Runoff is slow because much of the water that falls on this soil moves rapidly downward through the profile. This soil is suitable for corn and soybeans. It can also be used for wheat and for clover grown for hay, but it is less well suited to those crops. The soil does not hold plant nutrients well. Therefore, applying annually the amount of fertilizer needed is better than applying a large amount of fertilizer that is likely to be leached out of the soil. Nitrogen is generally needed, especially for corn. MANAGEMENT GROUP IVe-1 This management group consists of sloping to rolling, slightly eroded to severely eroded soils of the Blair, Hick- ory, Hosmer, and Velma series. These soils have a medium- textured or fine-textured plow layer that is underlain by an acid subsoil. In the severely eroded soils, the original surface layer has been washed away and the light-colored subsoil is now exposed. As a result, these soils are low in content of organic matter. In these soils the content of nitrogen and phosphorus is generally low and the content of potassium is low to medium. The available moisture capacity is moderate, and yields are limited by lack of moisture in most years. The strong slopes in many places, and the clayey texture of the present surface layer, cause water to run off rapidly in the severely eroded spots. Much of the water that should be stored in the soils rims off, causes erosion, and is therefore not available to plants. These soils are suited to hay and ineadow crops. Alfalfa and ladino clover generally yield well and make good pasture if they are grown in combination with tall fescue, bromegrass, or orchardgrass. Good stands of legumes are needed because of the low content of organic matter and nitrogen. Proper fertilization is needed for good stands of all crops. MANAGEMENT GROUP IVw-1 The only mapping unit in this management group is Cisne-Huey complex. The soils of that complex are nearly level and are poorly drained. Permeability of the subsoil is slow or very slow, and excess water does not move down- ward through the profile after the soils have l)ecome wet. Both the Cisne and Huey soils have an acid surface layer. The Cisne soil also has an acid subsoil, but the Huey soil has an alkaline subsoil that is high in content of sodium. Both the soils are low in content of organic matter, nitro- gen, phosphorus, and potassium. Their a\'ailab!e moisture capacity ranges from high, where the Cisne soil has re- ceived a large amount of fertilizer, to moderate or low in the Huey soil. These soils are suited to corn, soybeans, wheat, and clover. If more than the average amount of rainfall is re- ceived, however, corn and soybeans tend to turn yellow from lack of nitrogen because of the denitrification that takes place when the soils are wet. The soils are not well suited to oats, because they are usually too wet to till early in spring when oats should be sown. The reaction, or pll, of the plow layer needs to be kept at about 6.5 to 7.0. Care must be taken not to add excessive lime to the Huey soil, however, because that soil has an alkaline subsoil near the surface. The phosphorus and potassium in alkaline soils are less available to plants than in a soil that has a neutral to slightly acid plow layer. Open ditches are used to improve drainage in these soils, for tile drains will not fmiction because of the slow or very slow permeability of the subsoil. The surface layer has weak striicture, and heavy rains tend to make the soil material compact after plowing has been com- pleted. For this reason, these soils are plowed in spring. If they were plowed in fall, they would have to be plowed again in spring if the normal number of heavy rains is received. MANAGEMENT GROUP VIc-1 In this management group are strongly rolling and steep, light-colored soils of the Hennepin, Ilickory, and Negley series. These soils have a surface layer of loam to clay loam. Surface runoff is rapid, but much of the water from rainfall enters these soils if the cover of grass or trees is adequate. In general, the reaction of the surface layer ranges from medium acid to neutral, but it is alkaline in some areas. Areas of Hennepin soils that are intermingled with areas of Hickory soils are likely to have an alkaline surface layer. The content of phosphorus is low in most places, and the content of potassium is medium. The avail- able moisture capacity and permeability are generally moderate. These soils are too steep and easily eroded to be used for tilled crops, but they are well suited to pasture and hay. Most of the acreage is in pasture and woods, but man- aging meadow is dirticvdt in many places, because the areas are so steep. Extreme care is necessary to keep from over- turning ordinary farm machinery used for reseeding and mowing. Also, special care is necessary if three-wheeled tractors are operated on these soils. Many of the wooded areas are used as pasture. They supply only a small amount of forage of poor quality, however, and are worthless for fattening likestock. The likestock eat small trees and prevent reproduction of de- sirable kinds of trees. Their trampling also compacts the soils. As a result, the absorption of water is restricted and many roots that are near the surface are destroyed. Intensive grazing leaves the soils bare and subject to erosion. Farmers should select areas of these soils that are the best suited to trees or pasture. They then need to improve the wooded areas by protecting them from grazing. Trees can be planted where necessary, or the areas can be cleared and improved for pastures. Many of these soils have a sur- face layei' that is neutral or alkaline in reaction. Therefore, it is advisable to determine the pH value before pine trees are planted, for pines do not grow well on soils that are neutral to alkaline in reaction. Additional information about management of pastures on these soils can be found in the subsection "General Management of Soils Used for Pasture." Facts about management of wooded areas can be found in the subsection "Use of the Soils as Woodland." 56 SOIL SURVEY MANAGEMENT GROUP VIIc-1 In this management group are verj' steep, liglit-colored or moderately dark colored soils of the Hickory and Hen- nepin series. These soils have a loam surface layer. In ])laces, mainly in areas of Hennepin soils that are inter- mingled with ai-eas of Hickory soils, calcareous material is near the surface. These soils are well drained, have mod- erate available moisture capacity, and have a medium acid to alkaline surface layer. The slopes are too steep for fai'm machinery to l)e used in renovating pastures. Therefore, these soils are ordinar- ily better used for trees. Where pines are to be planted, the soils should be tested at the site, for pines make only poor growth or none at all in areas where the pH -^-ahie is high. Additional information about use of these soils for trees is given under "Use of the Soils as Woodland," in the discussion of woodland suitability group 1. Estimated Crop Yields Table 5 gives estimates of average acre yields of the principal crops grown in Montgomery County under two levels of management. These estimates are for yields ob- tained over periods long enough that they include the usual ranges in temperature and precipitation that occur in the county. Annual yields for a given soil and level of manage- ment, however, can range from 20 percent above the figures shown to 20 percent below. The extremes may be even greater if the weather is extremely unusual during a grow- ing season. In columns A are yields to be expected under a moderately high level of management practiced by many farmers whose management is above average. In columns B are yields to be expected under the high level of man- agement practiced by about 10 percent of the farmers in the county. Under the moderately high level of management used to obtain the yields in columns A, commercial fertilizer and lime are applied, but often in smaller amomits than needed for best returns; inadequate, but nearly adequate, practices are used to help control erosion and to improve drainage; the cropping system selected may not be espe- cially suitable; the population of plants may be either too low or too high; the supply of organic matter may be in- adequate, and the soils may not be in good tilth ; tillage and other cultural practices are inadequate; the kinds of seed may not be most suitable ; control of weeds, diseases, and harmful insects is inadequate ; or the proper combina- tion of i^ractices is not applied in the most timely manner. Under the high level of management iised to obtain the yields in columns B, adequate surface drainage and in- ternal drainage are provided; protection from flooding is provided where needed ; practices that help to control ero- sion are used ; tillage is not excessive and is properly done ; the proper kinds and amounts of seed of good quality are planted; and weeds, diseases, and harmful insects are con- trolled. Also, favorable soil reaction (about pH 6.5 for most crops) and an optimum level of available phosphorus and potassium are maintained for various crops by apply- ing lime, phosphate, and potash according to the needs indicated by the results of soil tests and previous management. A high level of management also includes using crop residue efficiently; applying barnyard manure; growing a crop for green manure; and using a cropping system designed to control erosion, to maintain the optimum amount of organic matter, and to facilitate the production and utilization of nitrogen in the soils. In addition, it in- cludes supplementing the supply of nitrogen in the soils l)y applying a nitrogen fertilizer, as needed; harvesting crops and incurring only minimal losses; and combining all of these jjractices efficiently so as to create the best growing conditions for each croj^ within the limits imposed by weather. Because conditions differ from field to field and the weather varies from one season to another, great skill and careful attention to details are required to attain a consistently high level of management. The estimates of yields are based on current informa- tion and can be expected to change as farming techniques, varieties of crops, and soil management improve. They are based on current data obtained from the results of research by the Illinois Agricultural Experiment Station; on rec- ords kept by farmers in cooperation with the University of Illinois Department of Agricultural Economics; and on the experience of scientists who specialize on informa- tion about soils and crops. Part of the information is the result of special research studies that were conducted to determine the yields of corn, soybeans, wheat, and alfalfa and mixed hay grown on the Carlinville Agronomy Re- search Field and managed in different ways.^ Herrick, Harrison, and Cowden silt loams are predominant in this field, and they are also extensive in the central and north- ern ]>arts of Montgomery County. All crops grown on the Carlinville field responded well to applications of lime and potash. Alfalfa responded well to phosphate, and wheat responded well to nitrogen and markedly well to applica- tions of phosphate, especially superphosphate. Applying 50 or 100 pounds of nitrogen to first-year corn that was preceded by alfalfa gave small increases in yields, but a greater increase in yields would be expected where corn is not preceded by alfalfa. Special studies of yields obtained where selected soils received special treatment were also carried on at the Brownstown Agronomy Research Center in Fayette Coun- ty.'^ The Cisne, Hoyleton, and Huey silt loams in the field where these experiments were conducted are similar to the same soils in the southeastern part of Montgomery County. Crops grown on those soils respond well to applications of lime and potash. In fact, lime and potash are essential for growing crops economically on those soils. The crops also respond well to applications of nitrogen and phosphate if those elements are applied in suitable combinations. Be- cause of the claypan in the subsoil, both drought and ex- cessive moisture lower yields to a greater extent than on more permeable soils. Use of the Soils as Woodland'' Originally, forests of deciduous hardwoods covered nearly 25 percent of Montgomery County, but now forests cover only about 10 percent. The county contains no State or national forests, and most of the wooded areas consist of farm woodlots, about 30 acres in size. All of these but one ^ Details of these studies are on file in the Department of Agron- omy. College of Agriculture, University of Illinois, Urbana, 111. "William R. Boggess, Department of Forestry, University of Il- linois, and Clark W. Rinker, woodland conservationist, Soil Con- servation Service, assisted in preparing this section. MONTGOMERY COUNTY, ILLINOIS 57 Table 5. — Estimated average acre yields oj principal crops [Yields in columns A are those to be expected under a moderately high level of management; yields in columns B are those to be expected under a high level of management. For yields on the soils of bottom lands, it is .assumed that no damage from flooding has occurred. Absence of a yield figure indicates that the soil is not well suited to the crop. or that the crop is not commonly grown.] Soil Corn Soyb eans Wheat Alfalfa hay Mixed rotation pasture Bluegrass pasture A B A B A B A B A B A B Blair silt loam, 5 to 9 percent slopes, eroded Blair soils, 5 to 9 percent slopes, severely eroded. _ Camden silt loam, 2 to 4 percent slopes Camden silt loam, 4 to 7 percent slopes, eroded.. Chauncev silt loam _ _ Bu. 43 35 69 59 68 61 50 70 79 67 55 49 69 67 62 64 70 73 72 66 68 63 73 74 60 45 38 32 Bu. 50 41 80 70 , 86 78 64 87 94 85 69 63 88 86 81 83 86 91 89 85 87 82 90 93 73- 50 44 39 Bu. 17 13 28 22 29 26 21 30 34 29 23 20 30 29 27 28 30 31 31 29 30 28 32 32 25 17 15 12 Bu. 20 16 32 26 34 30 25 35 37 34 28 25 34 33 31 32 34 36 35 33 34 32 36 37 30 20 18 15 Bu. 20 16 34 27 32 30 25 34 35 33 27 24 35 34 32 33 32 36 35 33 34 32 34 36 30 20 17 14 Bu. 23 19 40 33 39 36 30 41 42 40 34 30 41 40 38 39 39 44 42 40 41 39 42 45 38 23 20 17 21 18 15 Tons 1.7 1.3 3.0 2.6 2.6 2.5 2.0 2.8 3.0 2.7 2.2 1.9 2.9 2.8 2.6 2. 7 2. 9 3.0 2.9 2.7 2.8 2. 6 3.0 3.0 2. 4 1.8 L4 1. 1 1. 6 1.3 1.0 1. 4 Tons 2.8 2.4 4.0 3.6 3.7 3.5 3.0 4.0 4.0 3.9 3. 1 2.8 4. 1 4.0 3.8 3.9 3.9 4.3 4. 2 4.0 4. 1 3.9 4. 4.3 3. 2 2.8 2. 4 2. 1 2.5 2. 2 1. 9 2. 3 Animal- u nit- days 1 85 70 135 115 130 120 95 140 155 135 105 95 145 140 130 135 140 150 145 140 140 135 150 150 120 90 80 60 85 75 55 80 75 80 70 85 120 115 100 90 95 70 120 115 105 95 165 120 160 145 135 130 120 125 115 Animal- unit- days ' 135 115 185 165 180 165 130 190 210 185 150 135 205 200 185 190 195 210 205 195 200 190 205 210 170 140 130 100 135 120 95 130 120 130 115 135 170 165 150 130 140 110 165 160 150 130 235 170 225 205 185 180 170 • 175 160 Animal- unit- days 1 55 40 90 70 80 70 55 90 110 85 65 55 95 90 80 85 90 100 95 90 90 85 95 100 80 60 50 40 55 45 35 50 45 50 40 55 80 75 65 50 55 40 70 65 55 50 115 70 110 95 85 80 70 75 65 Animal- unit- days ' 85 75 125 110 115 Cisne silt loam 100 Cisne-Huey complex _ _ . _ 80 Clarksdale silt loam _ 125 Colo silty clay loam _ . 155 Cowden silt loam_ 120 Cowden-Piasa complex, to 2 percent slopes Cowden-Piasa complex, 2 to 4 percent slopes, eroded 95 85 Douglas silt loam, 2 to 4 percent slopes . 140 Douglas silt loam, 4 to 7 percent slopes 135 Douglas silt loam, 4 to 7 percent slopes, eroded. . Douglas silt loam, 7 to 12 percent slopes Ebbert silt loam 125 130 130 Harrison silt loam, to 2 pei-cent slopes Harrison silt loam, 2 to 4 percent slopes Harrison silt loam, 2 to 4 percent slopes, eroded.. Harrison silt loam, 4 to 7 percent slopes Harrison silt loam, 4 to 7 percent slopes, eroded.. Harvel silty clay loam 145 140 135 135 130 140 Herrick silt loam 145 Herrick-Piasa complex _ _ 115 Hickory loam, 7 to 12 percent slopes 90 Hickory loam, 7 to 12 percent slopes, eroded Hickory soils, 7 to 12 percent slopes, severely eroded 80 65 Hickory loam, 12 to 18 percent slopes 85 Hickory loam, 12 to 18 percent slopes, eroded 75 Hickory soils, 12 to 25 percent slopes, severely eroded 60 Hickory loam, 18 to 30 percent slopes 80 Hickory loam, 30 to 60 percent slopes 75 Hickory-Hennepin loams, 18 to 30 percent slopes. Hickorv-Hennepin loams, 30 to 60 percent slopes 1.2 2. 1 80 70 Hickory and Negley loams, 15 to 35 percent slopes 1.6 2.3 2.2 1.9 1.4 1.7 1.2 2.6 2.5 2.1 2.0 3.5 2.8 3.3 2.9 2.8 2.7 2.3 2.5 2.2 2.5 3.5 3.4 3.1 2.6 2.8 2.3 3.6 3.5 3. 1 2.9 4.8 3.8 4.3 4.2 4.0 3.9 3.5 3.7 3.4 85 Hosmer silt loam, 2 to 4 jDercent slopes Hosmer silt loam, 4 to 7 percent slopes 65 61 54 45 51 39 62 59 54 48 84 60 80 72 68 65 60 62 56 74 71 63 52 60 47 79 76 71 61 104 72 95 89 86 83 78 80 74 25 23 19 15 17 13 26 25 23 21 34 23 35 31 29 28 26 27 25 29 27 23 18 20 16 30 29 27 24 39 26 38 35 34 33 31 32 30 31 29 24 20 21 15 30 29 27 24 38 27 37 35 34 33 31 32 30 37 35 30 25 27 20 36 35 33 29 47 34 43 42 40 39 37 38 36 110 105 Hosmer silt loam, 4 to 7 percent slopes, eroded Hosmer soils, 4 to 7 percent slopes, severely eroded 95 80 Hosmer silt loam, 7 to 12 percent slopes, eroded Hosmer soils, 7 to 12 percent slopes, severely eroded _ _ . 85 70 1 Hoyleton silt loam, to 2 percent slopes Hoyleton silt loam, 2 to 5 percent slopes Hoyleton silt loam, 2 to 5 percent slopes, eroded__. ; Hoyleton-Tamalco complex, 1 to 4 percent slopes. 1 Ipava silt loam 100 95 85 80 165 ' Landes fine sandy loam.. 105 Lawson silt loam 160 \ Nokomis silt loam. . 140 j Oconee silt loam, to 2 percent slopes 120 Oconee silt loam, 2 to 4 percent slopes 115 Oconee silt loam, 2 to 4 percent slopes, eroded 1 Oconee silt loam, 4 to 7 percent slopes 105 110 1 Oconee silt loam, 4 to 7 percent slopes, eroded 100 See footnote at end of table. 58 SOIL SURVEY Table 5. — Estimated average acre yields oj principal crops — Continued Soil Oconeo-Tanialco complex, to 2 percent slopes.. Oconec-Tamalco complex, 2 to 4 percent slopes.. Oconee-Tamalco complex, 2 to 4 percent slopes, eroded Oconec-Tamalco complex, 4 to 7 percent slopes, eroded O' Fallon silt loam, 2 to 4 percent slopes Pana loam, 4 to 7 percent slopes, eroded Pana loam, 7 to 14 percent slopes, eroded Pike silt loam, to 2 percent slopes Pike silt loam, 2 to 4 percent slopes Pike silt loam, 4 to 7 percent slopes Pike silt loam, 4 to 7 percent slopes, eroded Pike silt loam, 7 to 12 percent slopes, eroded Racoon silt loam Radford silt loam Shiloh silty clay loam Shiloh silt loam, overwash Sicily silt loam, 2 to 4 percent slopes Sicily silt loam, 4 to 7 percent slopes, eroded Starks silt loam Stoy silt loam, to 2 percent slopes Stoy silt loam, 2 to 4 jjercent slopes Tamalco silt loam, 2 to 4 percent slopes Tamalco silt loam, 2 to 4 percent slojies, eroded Tamalco silt loam, 4 to 7 percent slopes, eroded-. Tcrril loam, 2 to 5 percent slopes \'elma loam, 4 to 7 percent slopes Velma loam, 4 to 7 percent slopes, eroded Velma loam, 7 to 12 percent slopes Velma loam, 7 to 12 percent slopes, eroded Velma loam, 12 to 18 percent slopes Velma- Walshville complex, 4 to 7 percent slopes, eroded Velma-Walshville complex, 7 to 12 percent slopes, eroded Virden silty clay loam Weir silt loam Corn Bu. 55 53 49 46 61 59 55 69 67 64 57 53 64 78 75 71 67 59 71 69 66 46 41 37 73 60 54 56 50 43 40 78 65 B 13u. 69 67 63 59 79 73 69 79 77 ,75 70 67 82 93 91 87 83 75 82 79 76 58 53 49 90 71 66 68 61 53 49 95 75 Soybeans Bu. 23 22 20 19 27 24 22 28 27 25 22 20 28 34 33 31 28 25 29 27 26 20 18 17 31 25 22 24 20 18 16 34 25 Bu. 27 26 24 23 32 28 25 32 31 29 26 24 32 37 36 35 33 30 33 31 30 23 21 20 36 28 25 27 23 20 18 38 29 Wheat Bu. 27 26 24 23 32 29 26 34 33 31 27 24 31 36 34 32 33 30 35 34 33 23 21 20 36 29 26 27 24 25 21 19 36 31 Bu. 32 30 28 27 38 35 32 40 39 37 33 30 37 42 41 37 40 37 41 39 38 27 25 24 43 34 31 32 28 29 25 22 44 36 Alfalfa hay Tons 2.2 2. 1 1. 9 1. 8 2. 5 2. 3 2. 2 2. 8 2.7 2. 6 3.2 2. 8 2. 6 2. 7 2. 4 3. 1 1. 4 3. 2. 4 2. 2 2. 3 2. 2. 1 1. 7 1. 6 3. 1 2.4 B Tons 3. 2 3. 1 2. 9 2.8 3. 3 3. 9 3. 3 3. 1 3. 6 4. 2 3. 8 3. 6 3. 9 3. 6 4. 1 3. 8 3.7 2. 8 2. 4 2. 3 3.4 3. 5 3. 1 3.3 2. 7 2. 6 4. 1 3.4 Mixed rotation pasture Animal- u nit- days ' 105 100 95 90 125 120 115 135 130 125 110 105 125 1.55 155 145 140 125 140 130 125 90 80 75 150 120 110 115 105 110 90 85 155 115 Animal- unit- days 1 145 140 135 125 175 170 165 185 180 175 160 150 175 210 205 195 190 175 190 180 175 125 120 115 210 175 165 170 155 160 130 120 215 165 Bluegrass pasture Animal- unit- days 1 60 55 50 45 75 75 70 90 85 80 70 65 75 110 100 90 90 80 100 90 85 50 40 35 100 80 70 75 65 70 55 55 105 80 Animal- unit- days 1 95 90 80 75 110 110 105 125 120 115 105 100 110 160 145 i 125 125 115 130 120 115 80 70 65 145 115 105 110 100 105 So 80 1.50 105 ' A term used to express the carrying capacity of pasture. It is the number of animal units carried per acre multiplied by the number of days the pasture is grazed during a single grazing season without injury to the sod. For example an acre of pasture that provides 30 days of grazing for two cows has a carrying capacity of 60 animal-unit-days. are privatel}' owned, and that one is municipally owned. Most of the wooded areas are in the southern and cen- tral parts of the county along West, Middle, and East Forks of Shoal Creek and along Dry Fork and Ramsey Creeks and their tributaries. Wooded areas consist mainly of Hickory, Hosmer, Stoy, Weir, and Lawson soils but some other soils are occupied by scattered wooded tracts. The present wooded tracts are generally poorly man- aged and mostly do not contain enough desirable species for high yields. Most of the wood now cut is sawed into lumber for local use, and some native timber is also used for posts and firewood. Most veneer logs and cooperage stocks are shipped to other States. The wood products used locally are processed mainly at sawmills located at Witt, at Hillsboro, and at a point 4 miles south of Hills- boro. The soils that should be used for trees will be naturally reforested with desirable trees if a suitable source of seed is available. Where no suitable source of seed is available, planting desirable kinds of trees brings the soils back into production. Records kept over a long period of time .show that about 60 acres of trees, on the average, is planted annually and that the main kinds of planted trees are coni- fers. Red pine and jack pine are the principal species planted, but some plantations of Scotch pine have been established. The Scotch pines are sold for Christmas trees. Forest types Forest types consist of stands of trees similar in com- position and develoi:)ment. In general, they vaiy accord- ine: to differences in the site. MONTGOMERY COUNTY, ILLINOIS 59 The oak-hickory tyj^e is the more extensive of the two types in Montgomery County. Wooded tracts consisting of this type occupy well-drained soils, and they consist primarily of black oak, white oak, hickory, red oak, Amer- ican elm, red elm, and white ash. Minor species are shingle- oak, black walnut, black cherry, bur oak, Osage-orange, black locust, honey locust, and post oak. Post oak com- monly grows on the more nearly level, poorly drained soils, and the areas in which they grow are called post oak flats. Trees of the hottom-land harchooods type grow on the flood plains of the major streams throughout the county. They are important for producing timber because they generally grow on soils that are highly productive. The principal kinds of trees of this tyi^e are silver maple, elm, Cottonwood, sycamore, and some basswood. Minor species are swamp white oak, pin oak, willow, ash, black walnut, and hackberry. Soil properties affecting production of trees The soils of this county differ Avidely in suitability for trees, just as they vary in suitability for other crops. The soil factors that influence the growth of trees, however, are somewhat different from those that affect the growth of annual crops or pasture. Trees are a long-term crop. They normally I'equire decades to mature, and the soils on Avhich they grow nonnally do not receive lime or fertilizer to help tree growth. The combination of species, or forest typ)es, that grow on a specific soil are determined chiefly by I a combination of such factors as position, slope, exposure, soil moisture, and other prop)erties of the soils. The com- bined effect of these factors on the growth of trees deter- mines the quality of the site. Among the more imi^ortant factors that affect the pro- ductive capacity of a soil for growing trees is the capacity of the soil to maintain an adequate moisture supply and to permit the development of an adequate root system. The [moisture-supplying capacity of a soil, in turn, is influ- ■enced by its depth, texture, permeability, aeration, and depth to the water table. Other significant soil character- istics that affect the growth of trees are the texture and ! thickness of the surface layer and subsoil, the supply of .plant nutrients, and the I'eaction (pH) of the soil. Some 'soils in the county have a high pH in the subsoil, caused Iby a high content of exchangeable sodium. Pines Avill not grow on these alkaline soils, or they make only poor igrowth. Erosion reduces the thickness of the favorable surface layer, and it also reduces the capacity of the soil to store Imoisture, causes increased nipoff, and lowers the amount of Avater that is absorbed. Natural reproduction of trees lis likely to be adversely affected by severe erosion. Woodland suitability grouping Management of Avoodland can be planned more effec- tively if soils ax"e grouped according to those character- istics that affect the growth of trees and management of the stand. For this reason, the soils of Montgomery County have been placed in seven Avoodland suitability groups. The soils most suitable for growing trees have been placed in woodland suitability groups 1 through 6, based on de- tailed studies of the characteristics of the soils and on information about the response of the soils to woodland use and management. Each group is made up of soils that require similar management and that have about the same potential productivity for Avood crops. Productivity is shown in tenns of site index and expected number of board feet of timber produced for named species based on the International scale (22). The number of board feet to be expected, as determined by the International scale, is based on an SO-year rotation. The soils that were developed under grass and that are generally more suitable for farming than for trees are jilaced in Avoodland suitahility group 7 on the basis of their characteristics. Since practically no trees noAv grow on the soils of group 7, the only information furnished for that group is the names of the series involved. Information on Avoodland suitability groups Avas ob- tained from many sources. A main source consisted of tAvo publications of the Illinois Technical Forestry Associa- tion (11, 12). Information from these publications was supplemented by local studies made of the growth rate of trees groAvmg on a number of different soil types. These studies were made cooperatively by Jolin Sester, farm forester. University of Illinois Cooperative Extension Sei-vice, and soil scientists of the Soil Conservation Service. In the AA'oodland suitability groups, the characteristics of the soils in the group are described first. Then, informa- tion about species suitability or species to favor in existing stands is giA^en. This is folloAA-ed by the estimated range in site index, estimated potential production by board feet, and species to faA^or for planting. Eatings for certain limitations, and for hazards that affect management, are also included. Among these are ratings for plant competi- tion, seedling mortality, equipment limitations, and erosion hazard. The names of the soils in each Avoodland group can be determined by referring to the "Guide to Mapping Units" at the back of this soil survey. FolloAving are explanations of the ratings given. Site Index. — This is the average height, in feet, of the dominant and codominant trees of a given species at a specified age. For upland oaks, it is the height obtained at 50 years of age, and for eastern cottouAvood, it is the height attained at 30 years of age. By determining the site index, the potential production in board feet per acre can be estimated {Jf,22). Limitations and Hazards. — Iinportant limitations of soils used for trees, and hazards uivolved Avhen the soils are used for trees, have been given ratings of slight., mod- erate., or severe. These ratings direct attention to the differ- ent kinds of management practices that are needed in managing Avooded tracts and the intensity with Avhich these practices must be applied. Following are definitions of these limitations and hazards. Plant competition refers to the rate at which uiiAvanted trees, shrubs, and weeds are likely to invade a site where an opening has been made in the canoj)y by fire, cutting, or other factors. This competition hinders the estahlishment and growth of desirable trees. A rating of slight indicates that competition from other plants is no special problem. A rating of moderate indicates that comiaetition from other plants does not ordinarily preA^ent the establishment of an adequate stand of the desired species of trees. De- veloping a fidly stocked stand may be delayed, hoAvever, because the seedlings take longer to become established and their initial growth is slowed. A rating of severe indicates that competition from other plants prevents desirable 60 SOIL SURVEY trees from restocking naturally. If seedlings are planted, competing plants must be controlled. Seedling mortality refers to the expected loss of natural or planted tree seedlings as a result of soil characteristics or topographic features, not as a result of plant competi- tion. It is assumed that the natural supply of seed is ade- quate, that the stock is good, that the seedlings are properly planted and cared for, and that other enviromnental fac- tors, such as climate, are normal. In Montgomery County a rating of slight with regard to seedling mortality has been given to all the soils, indicating that ordinary losses do not amount to more than 25 percent of the planted stock. Equipment limitation depends on soil characteristics and topographic features that restrict the use of equipment in planting, tending, or harvesting trees. For stands of trees on most of the soils in the coiuity, the equipment limitation is rated as slight^ which indicates that there is little or no restriction on the type of equipment or on the time of year the equipment can be used. The use of equipment may be limited somewhat while the soil is thawing after a freeze in winter, however, or for short periods after a heavy rain- fall. A rating of modera.te indicates that the use of equip- ment is restricted because the slopes are steep, or because the soils are wet for periods of up to 3 months. Where the slopes are short and steep, farm tractors and long chains are needed for conducting logging operations. A rating of severe indicates tliat the use of equipment is restricted be- cause of very steep or long slopes that require special har- vesting methods, or because, for more than 3 months dur- ing the year, the soils are too wet for the use of equipment. In an area northeast of Litclifield, for example, the equip- ment limitation is rated as severe because some of the slopes are steep and long. In that area track-type equipment may be needed for the most efficient operation. Erosion hazard refers to the potential risk of erosion if the site is managed according to acceptable standards for woodland use. Factors that influence these risks are the length and steepness of the slopes and the characteristics of the surface layer and subsoil. The ratings given for ero- sion hazard — slight^ moderate^ and severe — are based on the increasing risk of erosion that could be incurred in managing or harvesting a crop of trees. The hazard of ero- sion is generally related to the layout, use, and care of woods, roads, and skid trails, or to cultural practices that expose the soil. WOODLAND SUITABILITY GROUP 1 This group consists of deep, moderately well drained and well drained soils of the Camden, Hemiepin, Hickory, Negley, Pike, and Sicily series. These soils are nearly level to very steep and are on uplands and stream terraces. Their surface layer is medium textured and is light colored or moderately dark colored. Their subsoil is moderately fine textured. Permeability is moderate, and both the ability to supply nutrients to plants and the available moisture capacity are moderate to high. Reaction is generally me- dium acid, but the Hennepin soils have an alkaline subsoil. Before those soils are used for plantations of ])ines, they should be tested at the specific site to see if they are suitable. White oak and northern red oak are the species to favor in improving the present stands, and they are the most valuable trees now growing on the soils. Other species to favor are wliite ash, black oak, sugar maple, and black cherry. For upland oaks the site index ranges from 55 to 70. The annual potential yield of upland oaks ranges from 160 to 265 board feet per acre. Yellow-poplar, northern red oak, white oak, white ash, red pine, and white pine grow well if they are planted on these soils. Scotch pine is suitable only for growing as Cliristmas trees. Plant competition ranges from moderate to severe. It is severe in some of the gently sloping to rolling areas. In those areas several weedings are necessary for adequate re- stocking to take place. On the steeper slopes, competition is moderate. It does not prevent a fully stocked stand of desirable trees from becoming established, but natural re- generation is delayed. Also, one or two weedings are nec- esary for the survival of desirable seedlings. Seedling mortality is slight, and the expected loss of seedlings is less than 25 percent. Abandoned eroded areas should be planted to pines rather than hardwoods. The hazard of erosion is slight on the gently sloping soils. The hazard increases as the slope becomes steeper. Equipment limitations are moderate on the steeper slopes. Care is needed in conducting logging operations and in constructing roads. WOODLAND SUITABILITY GROUP 2 In this group are moderately well drained soils of the Hosmer and O'Fallon series that are moderately deep over a fragipan. These soils have a light-colored or moderately dark colored, medium-textured surface layer and a mod- erately fine textured subsoil. The upper part of their profile is moderately permeable, but the brittle, compact fragipan at a depth of 25 to 35 inches is very slowly permeable. The soils are on uplands and are gently sloping to rolling. ' They are very strongly acid, are low in natural fertility, | and have moderate to high available moisture capacity, j Response is good to proper management. \ White oak, northern red oak, and black walnut are the < species to be favored when improvement cuttings are made, and they are the most valuable species now growing in the wooded areas. Other species to be favored are black oak and black cherry. For upland oaks the site index ranges fi'om 60 to 75. The annual potential yield of upland oaks ranges from 195 to 300 board feet per acre. Rod ]iine (fig. 12) and white pine grow well if they are planted on these soils, and Scotch pine is suitable for plant- ing for Christmas trees. Black locust is siiitable for helping to control erosion or for use in stabilizing areas that are already eroded. Plant competition is moderate but usually does not pre- vent an adequate stand from becoming established. The initial growth of desirable species can be retarded by com- petition from undesirable species and other plants. Seedling mortality is slight. Ordinarily, adequate nat- ural regeneration takes place in areas that are not severely eroded. Care is necessary if severely eroded, sloping areas | are to be prepared for planting. In the severely eroded ' areas, the first plantings of pine seedlings are more produc- tive than plantings of hardwoods because tlie soils are bet- ter suited to pines than to hardwoods, and pines have a better survival rate. MONTGOMERY COUNTY, ILLINOIS 61 !«■ M A ■ I* ^' '^^, ■=>**" ■? '>--^^%*- T^'^ Figure 12. — Small plantation of red pine on a Hosmer soil of woodland suitability group 2. *.A' I .• P&^ Equipment limitations are slight. Erosion is not a serious hazard on the gently sloping soils, but the hazard in- creases as the steepness of the slope increases. On the stronger slopes, logging operations and the construction of roads should be done on the contour. WOODLAND SUITABILITY GROUP 3 This group consists of deep, light-colored to moderately dark colored, nearly level to sloping soils of the Clarksdale, Blair, and Stoy series. These soils are on the uplands. They are strongly acid and have a medium-textured surface layer and a moderately fine textured subsoil. Permeability is moderately slow or slow, and the available moisture capacity is moderate to high. Natural fertility of the Clarksdale soil is high, but it is medium in the Blair soils and low in the Stoy. Species to be favored for managing in the existing stands are white oak, black oak, northern red oak, basswood, and shingle oak. For upland oaks the site index ranges from 60 to YO. The annual potential yield of upland oaks ranges from 195 to 265 board feet per aci-e. Red pine, jack pine, and white ash grow well if they are planted on these soils. Scotch pine is suitable for growing as Christmas trees. Plant competition is moderate. Normally, it does not prevent desirable species from becoming established, but it can delay the natural regeneration of desirable trees and slow their initial growth. Seedling mortality is slight, and adequate natural re- generation generally takes place. Sassafras, hickory, and other less desirable species should be eliminated wherever more desirable species, for example white oak and ash, can be favored. The hazard of erosion is slight on the Clarksdale and Stoy soils, but it is greater on the Blair soils, especially until trees and other woodland plants become established. WOODLAND SUITABILITY GROUP 4 Weir silt loam, the only soil in this group, is deep, poorly drained, and slowly permeable. It is a nearly level soil of the uplands. The surface layer is light colored and medium textured, and the subsoil is moderately tine textured or Ime textured. This soil is strongly acid, has moderate avail- able moisture capacity, and is Ioav in natural fertility. 62 SOIL SURVEY Post oak, black oak, and white oak are the species to favoi' in the present stands. They are the most common trees now growing on this soiL For upland oaks the site index ranges from 46 to 57. The annual potential yield of upland oaks ranges fi'om 75 to 160 board feet per acre. Plant competition is moderate. It does not prevent an adequate stand of desirable species from becoming estab- lished. Seedling mortality is generally slight. Ordinarily, ade- quate natural regeneration takes place. At times, for periods of nearly 3 months, equipment used in managing woodland cannot be used when an abnormally large amount of rainfall has been received. Erosion is not a hazard. This soil has a limited root zone, however, which adversely affects the growth and stability of trees, especially conifers. WOODLAND SUITABILITY GROUP 5 This group consists of deep, light-colored to dark- colored, somewhat poorly drained soils of the Nokomis, Racoon, and Starks series. These soils are neai'ly level or gently sloping and are on stream terraces. They have a medium-textured surface layer and a moderately fine textured subsoil. Soil reaction ranges from strongly acid for the Racoon soil to slightly acid for the Nokomis and Starks. Permeability is moderately slow. The available moisture capacity and ability to supply nutrients to plants are medium to high. White oak, northern red oak, black oak, bur oak, and white ash are the species to favor when the stand of trees is improved. They are among the most productive trees that grow on these soils. For upland oaks the site index ranges from 67 to 74. The annual potential yield of upland oaks ranges from 230 to .'500 board feet per acre. In addition to white oak, northern red oak, black oak, bur oak, and wdiite ash, tulip-poplar, sycamore, cotton- wood, red pine, and white pine grow Avell if they are planted on these soils. Plant competition is moderate. It usually does not pre- vent desirable species from becoming established, but it can delay the natural regeneration of desirable trees and slow their initial growth. Seedling mortality is slight. Ordinarily, adequate nat- ural regeneration will take place. Equipment limitations are slight. Except for rather short periods after rains, work can be done any time of the year. Erosion is not generally a hazard on these nearly level to gently sloping soils. WOODLAND SUITABILITY GROUP 6 In this woodland group are deep, dark-colored, medium- textured and moderately coarse textured soils that occur on bottom lands. These soils are in the Landes, Lawson, and Radford series. They are someAvhat poorly drained and are slightly acid to neutral in reaction. The Lawson and Rad- ford soils are moderately permeable and have high avail- able moisture capacity. The Landes soil is rapidly permea- ble and has moderate to low available moisture capacity. The capacity to supply nutrients to plants is high for the Lawson and Radford soils and moderately high for the Landes soil. Cottonwood, sycamore, and black walnut grow rapidly on these soils and are the species to favor when the stand of trees is improved. ^Vliite ash and cherrybark oak are other species to favor, and tulip-poplar, cypress, and sweetgum also grow well. On the soils of this group, the site index for cottonwood is approximately 90. These soils are the most productive of wood crops of any in the county. Cottonwood, which grows in pure stands in places, makes the most rapid growth of any of the bottom-land hardwoods. More than 400 board feet per acre of lumber from cottonwood is pro- duced each year, and at times, the amiual yield exceeds 800 board feet per acre. Scattered areas of bottom lands, too small for economical use for farming, could be better used for growing cottonwoods. Because pines have Ioav tolerance for soils that are neutral or alkaline in reaction, they do not grow well on these soils. Plant competition from Aveeds, Adnes, loAv-groAving shrubs, and grass ranges from severe, Avhere only occasional flooding takes place, to moderate, Avhere flooding is fre- quent. Moderate competition from uuAvanted plants delays natural regeneration and slows the initial groAvth of trees. Usually, it does not prevent an adequate stand of desirable species from becoming established. Seedling mortality is slight on these soils for most kinds of ti'ees that are adapted to the climate and soils. Equipment limitations are moderate. Generally, ma- chinery can be used for 8 months each year Avithout serious damage to the roots of trees or to the structure of the soils. The use of equipment is someAvhat limited for about 3 months during many spring seasons. These soils are not ] subject to erosion. WOODLAND SUITABILITY GROUP 7 The soils of this group are generally cultivated, and for that reason they are not likely to be used as Avoodland. Some of the soils Avould be faA^orable sites for trees, and others Avould not. If planting of trees is contemplated, it Avould be necessary to refer to the folloAving series in the section "Descriptions of the Soils" to learn about the characteristics of the soils. Chauncey. Harvel. Pana. Cisne. Ilerrick. Shiloh. Colo. Iloyleton. Tamalco. CoAvden. Huey. Terril. Douglas. Ipava. Velma. Ebbert. Oconee. Virden. Harrison. Piasa. Walshville Planting of trees The slope, aspect, present A-egetation, and kinds of soils are the primary factors to consider Avhen choosing the kinds of trees to plant. Different kinds of trees vary in their requirements. For example, pines generally groAv better on drier, shalloAver, more acid, and more compact soils than do hardAA^oods, and they groAv in more exposed areas. Their groAvth is less rapid on these poorer sites, hoAvever, than on the more faA^orable sites. Because some strongly acid soils and alkaline soils occur in such a com- plex pattern, the soils should be tested before trees are planted so that the areas suitable for planting can be determined. The most important factors that affect the productive capacity of a soil for groAving trees is the capacity of that MONTGOMERY COUNTY, ILLINOIS 63 soil to maintain aeration and to permit the development of an adequate root system. Other soil characteristics that influence the growth of trees are the texture, depth, and consistence of the permeable soil material, and drainage, depth to the water table, and reaction. Pines, for example, do not grow or make only poor growth on alkaline soils. Cottonwoods and sycamores thrive on the soils of bottom lands where the supply of moisture is plentiful, but they do not grow or make only poor growth on dry soils of the uplands. A soil that formerly supported a specific kind of tree may not do so at present, because of soil changes, such as erosion. The planting information in the descriptions of the woodland suitability groups will assist tlie reader in choos- ing the kinds of trees to plant in a given area. More exact information can be obtained by consulting the local forester. Use of the Soils for Engineering Some soil properties are of special interest to engineers because they aft'ect the construction and maintenance of engineering projects. The soil pi'operties most important to engineers are grain size, plasticity, compaction charac- teristics, permeability, soil drainage, reaction, content of organic matter, and shrink-swell cliaracteristics. Also im- portant are susceptibility to flooding, depth to bedrock, and relief. The information in this soil survey provides a gaiide for engineers, not a complete manual. Its main value is for making preliminary studies of land use and soil proper- ties im})ortant to construction and engineering uses. The information in the survey, for example, can be used to make preliminary estimates of the engineering properties of the soils if a flood-prevention structure, agricidtural drainage system, farm pond, or irrigation system is planned, or if diversion terraces or waterways are to be constructed. This information can also be used if a site is to be selected for a highway, airport, industry, business, residence, or recreational area; if the suitability of the soils for cross-country movement of vehicles and con- struction equipment needs to be determined; or if prob- able sources of gravel and sand need to be located. With the use of the soil map for identification, the en- gineering interpretations reported here can be useful for many purposes. It should be emphasized that they do not eliminate the need for sampling and testing at the site of specific engineering works involving heavy loads and ex- cavations deeper than the depth of the layers here reported. Even in these situations, the soil survey may be useful for planning more detailed field investigations and for sug- gesting the kinds of problems that may be expected. Other information useful for engineering purposes can be obtained from the soil map. The distribution of differ- ent soils is shown on the map, for example, and general re- lief can be inferred from the slopes indicated in the names of the mapping units. It is often necessary, however, to refer to other parts of the survey. By using information ob- tained from the soil map, from the descriptions of the pro- files given in the section "Description of the Soils," and from the tables given in this subsection, the soils engineer 3an plan a detailed investigation of the soils at the site of ;onstruction. 294-384—69 5 In places the mapping units shown on the soil map in- clude small areas of a difl'erent kind of soil material. These inclusions are as large as 2 acres in size but are too small to be shown separately on the soil map. Normally, they are not significant for farming, but they can be important in engineering. Some of the terms used by the soil scientists may be un- familiar to the engineer, and some words — for example, soil, clay, silt, sand, and aggregate — may have special meaning in soil science. These terms, as well as other spe- cial terms, are defuied in the Glossary at the back of this soil survey. ]\Iuch of the information in this section is given in the tables. Table 6 gives engineering test data obtained when samples of soils from selected soil series were tested. Table 7 gives estimates of the properties of the soils, and table 8 provides engineering interpretations for these properties. Engineering classification systems Two systems of classifying soils are in general use among engineers. Both of these classification systems are described briefly in the following paragraphs. Additional informa- tion is given in the PCA Soil Primer (£1). AASTIO Olassification System. — Most highway engi- neers classify soil materials in accordance with the system approved by the American Association of State Highwa}'' Officials (AASPIO) {1). In this system soil materials are classified in seven basic groups that range from A-1 (gravelly soils of high bearing capacity, the best soils for subgrade) to A-7 (clayey soils having low strength when wet, the poorest soils for subgrade). Within each basic group, the relative engineering value of the soil material is indicated by a group index nuinber. Group index numbers range fi'om for the best material to 20 for the poorest. The group index numbers of the soils tested are shown in parentheses following the basic group symbol in table 6. The estimated AASHO classifications for the soils of IMontgomery County are given in table 7. Unified GlassifiGation System. — Some engineers prefer to use the Unified soil classification system originally de- veloped for the Corps of Engineers, U.S. Army {26) . The soils are classified under that system according to texture, plasticity, and performance as engineering construction material. In that system soil materials are identified as coarse grained (eight classes), fuie grained (six classes), or highly organic. A letter symbol and a descriptive name are used to indicate the principal characteristics of a given class. The symbols and their meanings are G, gravel; S, sand; M, silt; C, clay; O, organic silts and clays; Pt, peat and otlier highly organic soils; W, w^ell-graded material; P, poorly graded material; L, fine-grained matei'ial that has a low liquid limit; and H, fine-grained material that has a high liquid limit. Thus, a soil that has a Unified classi- fication of SP is a poorly graded sand. A soil that has a classification of ML is a silty soil that has a low liquid limit (50 or less). Table 6 shows the Unified classifications of the soils that were tested. The estimated Unified classifications for the soils of this county are given in table 7. Test data Table 6 shows test data for several soil types that occur in Montgomery County. The results of the testing, how- 64 SOIL SURVEY Table 6. — Engineering Soil type and location of sample Parent material Report number Depth Moisture-density data ^ Maxi- mum dry density Optimum moisture Douglas silt loam: T. 9 N., R. 2 W., sec. 22, SE160, SE40, NW. corner; thence 150 feet south and 30 feet east. (Modal profile) T. 10 N., R. 1 W., sec. 2; 150 feet south and 95 feet east of the NW. corner of the section. (Profile develoi^ed in shallow loess) Lawson silt loam: T. 9. N., R. 3 W., sec. 21, SE160, SW40, SWIG; 60 feet west and 25 feet north of road bridge. (Modal profile) Oconee silt loam: T. 9 N., R. 2 W., sec. 13, NE160, NW40, NE. corner; thence west 417 feet and south 88 feet. (Modal profile) T. 10 N., R. 4 W., near center of sec. 29. Reached by going from center of junction of State Highway No. 127 and oiled road, 350 feet east on the oiled road, and 10 feet south of the south edge of the road right-of-way. (Modal profile) Stoy silt loam: T. 8 N., R. 4 W., sec. 17, SW160, NW40, NE. corner; thence 200 feet south and 420 feet west or reached by going north of the road to a point 294 feet east of woods boundary. (Modal profile) Tamalco silt loam: T. 9 N., R. 4 W., sec. 26, NE160, NW40, NE. corner; thence 767 feet west and 78 feet south. (Modal profile) T. 7 N., R. 2 W., sec. 17, NW160, SW40, SW. corner of 40; thence 40 feet north and 3.5 feet east (Nonmodal profile) Walshville loam: T. 7 N., R. 5 W., sec. 2, SE160, SW40, SE. corner; thence 480 feet west along north side of right-of-way of new- road. (Modal profile) T. 10 N., R. 5 W., sec. 33, NW160, SW. corner; thence 180 feet north and 45 feet east. (Nonmodal profile) Loess overburden on paleosol in Illinoian glacial drift. Loess overburden on paleosol in Dlinoian glacial drift. Silty alluvium. Loess. Loess. Loess. Loess. Loess. Illinoian till and has a paleosol in the till in many places. Illinoian till and has a paleosol in the till in many places. 64-373 64-374 64-375 64-370 64-371 64-372 64-368 64-369 64-382 64-383 64-384 64-385 64-386 64-387 64-365 64-366 64-367 64-388 64-389 64-390 64-391 64-392 64-393 64-394 64-395 64-379 64-380 64-381 64-376 64-377 64-378 Inches 0-8 1.5-21 28-38 0-10 17-30 58-78 0-18 18-39 0-8 8-14 19-30 0-9 17-29 39-50 3-10 17-23 51-58 0-6 11-17 17-28 42-54 0-8 14-23 23-34 34-50 0-7 1.5-22 31-44 0-11 14-21 30-46 Percent 108 104 108 103 104 124 112 111 106 108 97 104 95 110 107 102 107 104 96 102 118 104 95 109 114 111 101 118 112 99 115 Percent 17 20 18 19 21 11 14 16 17 16 21 18 25 17 17 20 18 19 23 21 14 17 25 17 15 15 19 14 15 23 16 ' Tests performed by the Illinois Division of Highways, Bureau of Materials, Springfield, 111. 2 Based on AASHO Designation T 99-57, Method (1). 3 Mechanical analyses according to AASHO Designation T 88-57 (1). Results by this procedure frequently differ somewhat from results that would have been obtained by the soil survey procedure of the Soil Conservation Service (SCS). In the AASHO procedure, the fine material is analyzed by the hydrometer method and the various grain-size fractions are calculated on the basis of all the material, including that coarser than 2 millimeters in diameter. In the SCS soil survey procedure, the fine material is analyzed by the pipette method and the material coarser than 2 millimeters is excluded from calculations of grain-size fractions. The mechanical analyses used in this table are not suitable for use in naming textural classes for soils. MONTGOMERY COUNTY, ILLINOIS 65 test data ' Mechanical analysis ^' < Plastic- Classification Percentage passing sieve — • Percentage smaller than — ■ Liquid ity limit index AASHO Unified No. 10 No. 40 No. 200 0.05 mm. 0.02 mm. 0.005 mm. 0.002 mm. (2.0 mm.) (0.42 mm.) (0.074 mm.) 100 99 98 94 67 30 20 28 8 A-4(8) CL 100 100 98 99 99 93 91 94 88 77 74 62 41 36 29 36 30 21 52 48 34 28 25 10 A-7-6(18) A-7-6(16) A-4(8) CH CL 100 ML 100 72 99 43 96 41 76 32 40 18 29 13 49 22 25 6 A-7-6(16) A-4(2) CL 89' SM-SC 100 98 82 74 52 22 12 27 8 A-4(8) CL 99 96 76 70 54 24 14 29 9 A-4(8) CL 100 98 94 84 30 24 20 30 8 A-4(8) CL 100 97 94 85 32 26 22 29 9 A-4(8) CL 100 99 98 93 76 49 43 72 45 A-7-6(20) CH 100 98 94 67 58 24 21 28 7 A-4(8) ML-CL 100 100 99 96 82 52 41 70 43 A-7-6(20) CH 100 99 96 92 76 34 23 49 29 A-7-6(17) CL 100 96 93 87 65 26 18 31 11 A-6(8) CL 100 98 95 92 74 43 34 51 25 A-7-6(16) CL-CH 100 99 93 73 38 27 42 22 A-7-6(13) CL 100 96 93 84 59 26 19 30 7 A-4(8) ML 100 99 98 93 78 53 42 71 43 A-7-6(20) CH 100 99 97 92 76 47 32 61 36 A-7-6(20) CH 100 95 81 74 52 25 16 30 13 A-6(9) CL 100 96 93 88 54 20 13 28 7 A-4(8) ML-CL 100 99 96 82 53 45 68 37 A-7-5(20) CH 100 99 88 78 42 31 51 29 A-7-6(18) CL-CH ioo 99 96 91 68 33 28 33 15 A-6(10) CL 100 94 76 70 60 20 15 25 6 A-6(8) ML-CL 97 90 70 63 57 46 43 69 46 A-7-6(18) CH 94 81 56 50 44 30 28 47 30 A-7-6(13) CL 100 95 78 70 47 24 20 28 9 A-4(8) CL 98 95 80 75 64 48 40 68 43 A-7-6(20) CH 99 91 68 64 52 34 26 46 28 A-7-6(14) CL * In the Douglas profile developed in shallow loess, 100 percent of the soil material be tween a dep th of 58 and 78 inches p assed a 1-inch sieve. In the modal profile of the Lawso 1 soil, 100 percent of the soil material between a depth of 1 8 and 39 inches passec a No. 4 sieve. In the modal profile of the Walshville soi 1, 100 percent of the soil material between a dep th of 15 anc . 22 inches passed a %- nch sieve and 100 percent of the soil material between a depth of 31 and 44 inches passed a 1-inch sie ve. In the n onmodal profile of the \ Valshville soil. 100 percent of the soil ma terial between a depth of 14 and 46 ii iches passec a ^-inch s leve. 66 SOIL SURVEY Table 7. — Estimated [Lack of information Soil series and map symbols Blair (5C2, 5C3') Camden (134B, 134C2). Chauncey (287) Cisne (2,991) For properties of the Huey soil in 991 refer to the Huey series. Clarksdale (257) Colo (402). Cowden (112, 993A, 993B2) For propel ties of the Piasa soils in 993 A and 993 B2, refer to the Piasa series. Douglas (128B, 128C, 128C2, 128D) Ebbert (48). Harrison (127A, 127B, 127B2, 127C, 127C2). Harvel (252). Hennepin Herrick (45, 995). Depth to seasonal high water table Hickory (8D, 8D2, 8E, 8E2, 8F, 8G, 803,' 8E3, 997F, 997G, 998F). For properties of the Hennepin soils in 997 F and 997 G, refer to the Hennepin series; for properties of the Negley soil in 998 F, refer to the Negley series. Hosmer (214B, 214C, 214C2, 214D2, 21403,' 214D3.1) See footnotes at end of table. Feet 3-5 5-10 0-1 0-1 1-3 0-1 0-1 0-1 3-5 0-1 (') 1-3 Classification Depth from surface 5-10 Indies 0-7 7-60 0-8 8-40 40-90 0-36 36-60 0-21 21-40 40-60 0-14 14-44 44-65 0-23 23-5S 0-19 19-45 45-57 0-11 11-48 48-70 0-24 24-48 48-72 0-15 15-43 43-60 0-10 10-56 56-65 0-12 12-60 0-16 16-54 54-65 0-10 10-42 42-60 0-11 11-28 28-50 50-68 USDA texture Silt loam to loam. Clav loam Silt loam to loam Silty clay loam to clay loam Stratified loam, silt loam, and sandy loam. Silt loam Silty clay loam to silty clay Silt loam Silty clay loam to silty clay. Silty clay loam Silt loam Silty clay loam Silt loam to clay loam. Silty clay loam Mainly silty clay loam but con- tains strata of othei textures. Silt loam Silty clay loam to silty clay_ Silt loam Silt loam Silty clay loam Sandy loam to loam . Silt loam Silty clay loam Silt loam to clay loam. Silt loam Silty clay loam Silt loam to tilty clay loam_ Silty clay loam Silt loam or silty clay loam. Clay loam to silt loam Loam Loam to sandy loam. Silt loam Silty clay loam. Silt loam Loam Clay loam to loam Loam to sandy loam. Silt loam Silty clay loam Silt loam to silty clay loam. Silt loam Unified AASHO ML or CL CL ML or CL CL or CH ML, CL, SM or SC ML or CL CL or CH ML or CL CL or CH CL ML or CL CL or CH ML or CL CL, CH, or MH CL ML or CL CL or CH ML or CL ML or CL CL SM, SC, or ML ML or CL CH ML or CL ML or CL CL ML or CL CL CL or ML CL ML ML or SM ML or CL CH CL ML or CL CL ML, CL, or SM ML or CL CL ML or CL ML or CL A-4 or A-6 A-6 A-4 A-6 or A-7 A-2, A-4, or A-6 A-4 A-7 A-4 A-7 A-6 or A-7 A-4 or A-6 A-7 or A-6 A-4 or A-6 A-7 A-6 or A-7 A-4 A-7 A-4 or A-6 A-4 A-6 or A-7 A-4 or A-6 A-6 A-7 A-6 or A-7 A-6 A-6 or A-7 A-4 or A-6 A-7 A-7 or A-6 A-6 A-4 A-4 or A-2 A-4 or A-6 A-7 A-6 A-4 or A-6 A-6 A-4 A-4 A-6 or A-7 A-6 or A-7 A-4 or A-6 MONTGOMERY COUNTY, ILLINOIS 67 properties of soils indicates not api^licablc] Percent passing sieve- No. 4 (4.7 mm.) 95-100 95-100 100 95-100 90-100 100 100 100 100 100 100 100 100 100 95-100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 95-100 90-100 90-100 100 100 100 95-100 95-100 95-100 100 100 100 100 No. 10 (2.0 mm.) No. 200 (0.074 mm.) 90-100 90-95 95-100 90-100 80-95 95-100 95-100 95-100 95-100 90-100 100 100 100 95-100 90-100 100 100 100 100 100 90-100 100 100 90-100 100 100 95-100 100 100 90-100 90-100 85-100 100 100 100 90-100 90-100 90-100 100 100 100 95-100 85-100 60-80 80-95 60-90 30-80 95-100 90-95 95-100 90-95 80-95 95-100 95-100 95-100 90-100 80-100 95-100 95-100 95-100 95-100 95-100 40-70 95-100 95-100 80-95 95-100 95-100 90-95 95-100 95-100 80-90 50-80 30-70 95-100 95-100 95-100 50-80 55-85 40-80 95-100 95-100 95-100 90-100 Permeability Available water capacity Inches per hour 0. 63-2. 00 0. 20-0. 03 0. 63-2. 00 0. 63-2. 00 0. 63-2. 00 0. 20-0. 63 0. 06-0. 20 0. 20-0. 63 0. 20-0. 63 0. 63-2. 00 0. 20-0. 63 0. 20-0. 63 0. 63-2. 00 0. 63-2. 00 0. 20-0. 63 0. 06-0. 20 0. 06-0. 20 0. 63-2. 00 0. 63-2. 00 0. 63-2. 00 0. 63-2. 00 0. 06-0. 63 0. 06-0. 63 0. 63-2. 00 0. 63-2. 00 0. 20-2. 00 0. 63-2. 00 0. 63-2. 00 0. 63-2. 00 0. 63-2. 00 0. 63-2. 00 0. 63-2. 00 0. 20-0. 63 0. 20-0. 63 0. 63-2. 00 0. 63-2. 00 0. 63-2. 00 0. 63-2. 00 0. 63-2. 00 0. 06-0. 20 0. 20-0. 63 Inches per inch of soil depth 0. 20-0. 25 0. 10-0. 19 0. 20-0. 25 0. 16-0. 19 0. 12-0. 16 0. 20-0. 25 0. 15-0. 19 0. 20-0. 25 0. 18-0. 23 0. 18-0. 21 0. 20-0. 25 0. 19-0. 21 0. 18-0. 23 0. 19-0. 23 0. 19-0. 21 0. 20-0. 25 0. 15-0. 19 0. 18-0. 23 0. 20-0. 25 0. 19-0. 23 0. 14-0. 16 0. 20-0. 25 0. 19-0. 23 0. 18-0. 23 0. 20-0. 25 0. 19-0. 23 0. 18-0. 20 0. 20-0. 25 0. 18-0. 23 0. 18-0. 23 0. 14-0. 18 0. 12-0. 14 0. 20-0. 25 0. 19-0. 23 0. 18-0. 23 0. 16-0. 20 0. 16-0. 20 0. 10-0. 14 Reaction pH 5. 6-6. 5 5. 1-5. 5 5. 6-6. 5 5. 1-6. 5 5. 1-7. 5. 1-6. 5. 6-6. 5 4. 5-5. 4. 5-5. 5. 6-7. 8 0. 1-6. 5. 1-6. 5 5. 6-7. 3 6. 1-7. 3 6. 1-7. 3 5. 1-6. 5. 6-6. 5 5. 6-7. S 5. 6-6. 5 5. 1-6. 5. 6-6. 8hrink-s\vell potential Low to moderate - Moderate Low to moderate - Moderate Low to moderate - Low to moderate- Moderate to high. Low to moderate. High Moderate to hlgli. Low to moderate- High Low to moderate- High Moderate to high- Low to moderate- Moderate to high- Low to moderate - Low to moderate- Moderate Moderate to low. 5. 6-6. 5. 6-7. 3 5. 6-7. 3 5. 6-6. 5 5. 6-6. 5 6. 6-7. 3 6. 6-7. 3 6. 6-7. 3 6. 5-7. 8 6. 6-7. 8 * 7. 4-8. 3 5. 1-6. 5. 1-6. 5. 6-6. 5 4. .5-5. 5 4. 5-5. 5 5. 6-7. 8 Low to moderate- Moderate to high- Moderate Moderate Moderate to high. Low to moderate- Moderate- Moderate- Moderate. Low- Low- Low to moderate- High Moderate Low to moderate- Moderate Low to moderate- Corrosion potential for metal conduits High. Moderate. Moderate. High. High. High. High. High. High. High. High. Moderate. Moderate. High. High. Moderate. Moderate. High. High. Low. Low. High. High. Moderate. Moderate. 0. 20-2. 00 0. 19-0. 23 {') 5. 1-6. 4. 5-5. 5 4. 5-5. 5 5. 1-6. Low to moderate Moderate Moderate Low to moderate Moderate. Moderate. Moderate. 68 SOIL SURVEY Table 7. — Estimated Soil series and map symbols Depth to seasonal high water table Depth from surface Classification USDA texture Unified AASHO Hoyleton (3A, 3B, 3B2, 992B) For properties of the Tamalco soil in 9928, refer to the Tamalco series. Huey Ipava (43). Landes (304). Lawson (451). Negley Nokomis (586). Oconee (113A, 113B, 113B2, 113C, 113C2. 994A, 994B, 994B2, 994C2). For properties of the Tamalco soils in 994A, 994B, 994B2, and 994C2, refer to the Tamalco series. O'Fallon (114B)__ Pana (256C2, 256D2). Piasa. Pike (583A, 583B, 583C, 583C2, 583D2). Racoon (109) Radford (74) Shiloh (138, 138 + 9) Sicily (258B, 258C2) Feet 1-3 0-1 1-3 3-5 1-3 (^) 1-3 1-3 5-10 (') 0-1 (') 0-1 1-3 0-1 5-10 Inches 0-11 11-37 37-60 0-10 10-33 33-60 0-17 17-45 45-60 0-10 10-50 0-39 39-53 0-13 13-48 48-109 0-60 0-15 15-50 50-60 0-12 12-31 31-44 44^60 0-12 12-96 96-107 0-12 12-37 37-62 0-10 10-46 46-56 0-24 24-60 0-24 24-60 0-36 36-60 0-11 11-46 46-68 Silt loam Silty clay loam to silty clay Silt loam to silty clay loam Silt loam Silty clay loam to silty clay Silt loam Silt loam Silty clay loam to silty clay Silt loam Fine sandy loam to sandy loam Loamy fine sand to fine sand___ Silt loam or loam Stratified silt loam and loam._ Loam to sandy loam Sandy clay loam to sandy loam Sandy loam to sandy clay loam Loam to light silty clay loam. . Silt loam Silty clay loam to silty clay. Loam Silt loam Silty clay loam. Silty clay loam. Silt loam Silt loam to loam... Gravelly clay loam. Stratified gravel and sand. Silt loam Silty clay loam to silty clay. Silt loam to siltv clay loam. Silt loam Silty clay loam to clay loam. Silt loam to sandv loam Silt loam Silty clay loam. Silt loam Silty clay loam. Silty clay to silty clay loam. Heavy silt loam Silt loam Silty clay loam Silt loam to silty clay loam. ML or CL CL ML or CL A-4 A-6 or A-7 A-6 or A-7 ML or CL CL CL A-4 or A-6 A-6 A-6 ML or CL CH or Mil ML or CL A-6 A-6 or A-7 A-6 SM or ML SM A-4 A-2 or A-4 ML or CL ML or CL ML, CL, or SM CL, ML, SC, or SM SM, SC, or ML ML or CL ML or CL CL or CH ML or CL ML or CL CL ML or CL ML or CL ML or CL SC, GC, or CL GW, GC, SW, or SC ML or CL CH CL ML or CL CL SM or ML ML CL or CH ML or CL CL CH MH or CH ML or CL CL ML or CL A-4 or A-6 A-4 or A-6 A-4 A-4 or A-6 A-4 or A-6 A-4 or A-6 A-4 A-6 or A-7 A-4 or A-6 A-4 A-6 or A-7 A-6 or A-7 A-4 or A-6 A-4 A-2 or A-4 A-1 or A-2 A-6 or A-7 A-7 A-7 A-4 A-6 or A-7 A-2 or A-4 A-4 A-6 or A-7 A-4 or A-6 A-6 A-7 A-6 A-6 A-6 or A-7 A-4 or A-6 See footnotes at end of table. MONTGOMERY COUNTY, ILLINOIS 69 properties of soils — Continued Percent passing sieve- No. 4 (4.7 mm.) No. 10 (2.0 mm.) No. 200 (0.074 mm.) Permeability Available water capacity Reaction Shrink-swell potential Corrosion potential for metal conduits 100 100 100 100 100 100 100 100 100 100 100 100 95-100 95-100 95-100 85-95 90-100 100 100 100 100 100 100 100 90-95 65-90 50-70 100 100 100 100 95-100 85-95 95-100 95-100 95-100 95-100 100 100 100 100 100 9.5-100 9.5-100 90-100 9.5-100 95-100 90-100 100 100 100 95-100 95-100 95-100 85-95 90-95 90-100 80-90 85-95 100 100 70-80 100 100 100 95-100 85-90 60-85 40-60 95-100 95-100 95-100 95-100 90-100 75-85 95-100 95-100 95-100 95-100 100 100 100 100 95-100 9.5-100 90-100 80-95 95-100 90-100 80-95 95-100 95-100 95-100 35-65 15-45 80-100 55-95 40-70 40-70 40-60 60-90 9.5-100 9.5-100 60-75 95-100 9.5-100 95-100 90-100 55-70 30-60 0-15 9.5-100 95-100 95-100 70-90 60-90 30-55 95-100 95-100 95-100 95-100 95-100 95-100 9.5-100 95-100 95-95 Inches per hour 0. 63-2. 00 0. 06-0. 20 0. 20-0. 63 0. 20-0. 63 0. 06-0. 20 0. 63-2. 00 0. 63-2. 00 0. 63-2. 00 2. 00-6. 30 6. 30-20. 0. 63-2. 00 0. 63-2. 00 2. 00-6. 30 2. 00-6. 30 2. 00-6. 30 0. 63-2. 00 0. 20-0. 63 0. 06-0. 20 0. 20-0. 63 0. 63-2. 00 0. 63-2. 00 0. 06-0. 20 0. 06-0. 20 2. 00-6. 30 2. 00-6. 30 (.') 0. 20- (6) («) 0. 63- 0. 63- 0. 63- 0. 20- {') 0. 63- 0. 63- 0. 06- 0. 20- 0. 63 -2. 00 -2. 00 -2. 00 -0. 63 2. 00 2. 00 0. 63 0. 63 0. 63-2. 00 0. 63-2. 00 0. 20-0. 63 Inches per inch of soil depth 0. 20-0. 25 0. 18-0. 20 0. 16-0. 18 0. 20-0. 25 7 0. 12-0. 15 ' 0. 15-0. 18 0. 23-0. 27 0. 20-0. 25 0. 1 8-0. 23 0. 13-0. 17 0. 06-0. 08 0. 20-0. 25 0. 16-0. 20 0. 12-0. 14 0. 14-0. 18 0. 14-0. 16 0. 16-0. 19 0. 20-0. 25 0. 15-0. 18 0. 15-0. 18 0. 20-0. 25 0. 18-0. 23 5 0. 18-0. 20 0. 18-0. 23 0. 14-0. 18 0. 02-0. 04 0. 20-0. 25 ' 0. 1.5-0. 19 ' 0. 1.5-0. 18 0. 20-0. 25 0. 16-0. 19 0. 10-0. 14 0. 18-0. 23 0. 18-0. 20 0. 20-0. 25 0. 19-0. 21 0. 20-0. 25 0. 20-0. 25 0. 20-0. 25 0. 19-0. 21 0. 18-0. 21 pH 4. 5-5. 4. 5-5. 5 6. 1-7. 3 5. 6-6. 5 7. 9-9. 7. 9-9. 5. 6-6. 5 5. 6-6. 5 6. 1-7. 8 6. 6-7. 3 6. 6-7. 3 6. 6-7. 8 6. 6-7. 8 5. 1-6. 5 5. 0-6. 5 5. 0-6. 5 6. 1-7. 3 5. 1-6. 5 5. 1-6. 5 5. 6-7. 8 6. 1-6. 5 4. 5-5. 5 4. .5-.5. 5 4. .5-6. 5. 1-6. 5 5. 6-6. 6. 1-7. 8 6. 0-7. 7. 4-8. 4 7. 4-8. 4 5. 1-5. 5 5. 1-5. 5 5. 1-5. 5 5. 1-6. 5 5. 1-5. 5 6. 6-7. 3 6. 6-7. 8 6. 1-7. 3 6. 1-7. 3 5. 6-6. 5 5. 1-6. 5 6. 6-7. 8 Low to moderate. Moderate to high. Moderate Low to moderate- Moderate to high. Moderate to high. Moderate Moderate to high. Low to moderate- Low Low Moderate Moderate Low Low Low Low to moderate. Low to moderate- Moderate to high Low to moderate. Low to moderate. Moderate Moderate Low to moderate. Low Low Low Low to moderate- High Moderate to high Low to moderate. Moderate Low Low to moderate. Moderate to high Low to moderate - Moderate High Moderate Moderate Moderate to high Low to moderate- High. High. High. High. High. Moderate. Low. High. Moderate. Moderate. High. High. High. Moderate. Moderate. Moderate. Low. Low to moderate. Low. High. High. Moderate. Low. High. High. High. High. Moderate. Moderate. 70 SOIL SURVEY Table 7. — Estimated Soil series and map symbols Depth to seasonal high water table Depth from surface Classification USDA texture Unified AASHO Starks (132). Stoy (164A, 164B). Tamalco (581 B, 581 82, 581 C2). Terril (587 B). Velma (250C, 250C2, 250D, 250D2, 250E, 996C2, 996 D2). For properties of the Walshville soils in 996C2 and 996 D2, refer to the Walsh- ville series. Virden (50) Walshville. Weir (165). Feet 1-3 1-3 3-5 3-5 5-10 0-1 5-10 0-1 Inches 0-10 10-34 34r-68 0-14 14^51 51-58 0-9 9-28 28-42 42-60 0-48 48-90 0-18 18-70 70-100 0-14 14-53 53-60 0-14 14-21 21-80 0-15 15-48 48-60 Silt loam Silty clay loam to clay loam. . Stratified loam, silt loam, and sandy loam. Silt loam Silty clay loam Silt loam Silt loam Silty clay loam to silty clay__. Silt loam Clay loam or loam Loam to silt loam Loam, silt loam, clay loam, or silty clay loam. Loam Clay loam to silty clay loam_. Sandy loam to loam Silty clay loam Silty clay loam Silt loam to silty clay loam Silt loam to loam Clay loam to silty clay loam_. Loam to clay loam Silt loam Silty clay loam Silt loam ML or CL CL ML, CL, SM or SC ML or CL CL or CH ML or CL ML or CL CH CL CL ML or CL ML or CL ML or CL CL ML or CL CL CL or CH ML or CL ML or CL CH CH or CL ML or CL CL or CH ML or CL A-4 or A-6 A-6 or A-7 A-4 or A-6 A-4 or A-6 A-6 or A-7 A-6 or A-7 A-4 A-7 A-6 A-6 A-4 or A-6 A-4 or A-6 A-4 or A-6 A-6 or A-7 A-4 A-6 or A-7 A-7 or A-6 A-6 A-4 A-7 A-6 or A-7 A-4 A-6 or A-7 A-4 or A-6 ' In this soil at least the uppermost foot of soil material shown in the column "Depth from surface' 2 Less than 0.20. ^ More than 5. * Calcareous. has been removed bv erosion. ever, do not represent the entire range of soil character- istics within the county or even within the several soil types sanii^led. The results of the tests can he used as a gen- eral guide, nevertheless, in estimating the properties of the other soils in this county. The tests were i)erformed by the Illinois Division of Highways, Bureau of Materials, Springfield, 111. Table 6 gives compaction {7noisture density) data for the tested soils. If a soil material is compacted at suc- cessively higlier moisture content, the density of the com- pacted material increases until the ojjtlmum moisture content is reached, assuming that the compactive effort remains constant. After that, the density decreases with increase in moisture content. The highest dry density ob- tained in the compaction test is termed maxhnvm dry den- sity. Data that give moisture density are important in earthwork, for as a rule, optimum stabilit^^ is obtained if the soil is compacted to about the maximum diy density when it is at approximately the optimum moisture content. Mechanical analysis refers to the measurement of the amounts of various size classes of soil grains (sand, silt, or clay) in a sample. Proportions of the size classes deter- mine the textural class of the material. Names used by engineers for Aarious size classes of particles ditfer from those used by soil scientists. For example, fine sand in engi- neering terminology consists of particles 0.42 to 0.074 millimeter in diameter, whereas fine sand, as determined by the soil scientist, consists of particles 0.25 to 0.10 milli- meter in diameter. The tests to determine liquid limit and plastic limit measure the effect of water on the consistence of the soil material. As the moisture content of a clayey soil increases from a very dry state, the material changes from a semi- solid to a plastic. As the moisture content is further in- creased, the material changes from a plastic to a liquid. Tlie plastic limit is the moisture content at which the soil material passes from a semisolid to a plastic. The liquid limit is the moisture content at Avhich the material passes MONTGOMERY COUNTY, ILLINOIS 71 properiies oj soils — Continued Percent joassing sieve — Permeability Available water ca]5acity Reaction Shrink-swcll potential Corrosion No. 4 (4.7 inin.) No. 10 (2.0 mm.) No. 200 (0.074 mm.) potential for metal conduits Inches per inch of 100 95-100 90-100 95-100 90-100 80-95 80-95 60-90 35-80 Inches per hour 0. 63-2. 00 0. 20-2. 00 0. 63-2. 00 soil depth 0. 20-0. 25 0. 16-0. 19 0. 15-0. 18 pH 5. 1-6. 5 5. 0-5. 6 6. 1-7. 3 Low to moderate Moderate to high Low to moderate High. Moderate. 100 100 100 100 100 95-100 95-100 95-100 90-100 0. 20-0. 63 0. 06-0. 20 0. 20-0. 63 0. 20-0. 25 0. 15-0. 18 0. 18-0. 20 5. 1-6. 4. 5-5. 4. 5-5. Low to moderate Moderate to high Low to moderate High. High. 100 100 100 95-100 95-100 95-100 95-100 70-90 95-100 95-100 95-100 60-80 0. 20-0. 63 C) 0. 20-0. 25 0. 19-0. 21 ' 0. 15-0. IS ' 0. 14-0. 16 5. 1-6. 5 5. 6-7. 8 7. 9-8. 4 7. 9-8. 4 Low to moderate High Moderate Moderate High. High. High. 95-100 95-100 90-100 90-100 85-100 85-100 0. 63-2. 00 0. 63-2. 00 0. 18-0. 20 0. 18-0. 20 6. 6-7. 3 6. 6-7. 3 Low Low Moderate. Moderate. 95-100 95-100 95-100 90-100 90-100 90-100 50-80 55-85 50-90 0. 63-2. 00 0. 63-2. 00 0. 20-2. 00 0. 16-0. 20 0. 16-0. 19 0. 10-0. 14 4. 5-6. 4. 5-6. 5 5. 6-7. 8 Low to moderate Moderate Moderate. Low to moderate Moderate. 100 100 100 100 100 100 95-100 95-100 95-100 0. 63-2. 00 0. 20-0. 63 0. 63-2. 00 0. 19-0. 23 0. 18-0. 20 0. 18-0. 23 6. 1-7. 3 6, 1-7. 3 6. 6-7. 8 High Moderate to high Moderate High. High. 95-100 90-95 80-90 95-100 70-90 70-85 7.5-90 70-85 5.5-80 0. 63-2. 00 0. 20-0. 63 (-) 0. 16-0. 20 ' 0. 14-0. 16 0. 14-0. 16 5. 1-6. 5 5. 1-6. 5 7. 4-8. 4 Moderate High Moderate to high High. High. 100 100 100 100 100 95-100 95-100 95-100 90-100 0. 20-0. 63 0. 00-0. 20 0. 20-0. 63 0. 20-0. 25 0. 18-0. 20 0. 18-0. 23 5. 1-6. 4. 5-6. 5. 6-6. 5 Low to moderate Moderate to high Low to moderate High. High. 5 Roots generally cannot u.se moisture at this depth, because the fragipan restricts their development and penetration. 6 Less than 0.06. ' Roots generally do not penetrate to this depth, because of the dense subsoil and high sodium content. 8 More than 6.30. " In the 138+ mapping unit, about 10 inches of overwash covers the surface. from a plastic to a liqtiid. The plasticity index is the nu- merical difl'erence between the liquid limit and the plastic limit. It indicates the range of moisture content within which soil material is in a plastic condition. Engineering properties of the soils For the soils of each soil series in the county, table 7 gives some of the characteristics that are significant to engineering. The estimated properties are those of the typical soil profile, which is divided into layers significant to engineering. Where test data such as those in table 6 were available, those data were used. Where the soils were not tested, the estimates shown are based on comparisons with the soils of this county that were tested and on com- parisons with similar soils in other counties. Depth to bedrock is not estimated in table 7, because bed- rock is near the surface in only a few places and generally is not a limitation to engineering work. The places where 294-3S4— 69 6 bedrock is near the surface are mainly north of Nokomis, east of Litclifield, and west of Panama. In table 7 permeability of the soil as it occurs in place was estimated. The estimates are based on the stiiicture, porosity, and consistency of the soil material and on field observations. The estimates were compared with the re- sults of tests for permeability on undisturbed cores of simi- lar soil material. Available water capacity, expressed in inches per inch of soil depth, refers to the approximate amount of cap- illary water in a soil that is wet to field capacity. When the soil is air diy, this same amomit of water will wet the soil material to a depth of 1 inch without deeper percolation. The estimates are based on data from undisturbed soil samples or from field measurements of selected soils. Shrink-swell potential is an indication of the volume cliange to be expected of the soil material when the content of moisture changes. It is estimated on the basis of the amount and type of clay in the soil. In general, soils 72 SOIL SURVEY Table 8. — Interpretations oj Soil series and map symbols Suitability as a source of — Topsoil Sand or sravel Highway sub- grade material Soil features affecting suitability for engineering practices Highway location Farm ponds Reser\oir area Blair (5C2, 5C3). Camden (134B, 134C2)_ Chauncey (287). Cisne (2, 991) For interpretations for the Huey soil in 991, refer to the Huey series. Clarksdale (257) . Colo (402). Cowden (112, 993A, 993B2). For interpretations for the Piasa soils in 993 A and 993 B2, refer to the Piasa Douglas (128B, 128C, 128C2, 128D). Fair in surface layer of 5C2, and poor in surface layer of 5C3; in 5C3 most of the sur- face layer has been lost and the remaining material is clayey. Good in surface layer. Fair in surface layer. Fair in surface layer. Good to a depth of 12 inches. Fair to a depth of 24 inches; some- what clayey; site is often wet. Good to a depth of 12 inches. Good to a depth of 12 inches; fair to a depth of 30 inches. Not suited. Poor to fair. Not suited. Not suited. Not suited. Not suited. Not suited. Not suited. Possible depos- its of sand and low-grade gravel below a depth of 4 to 5 feet. Poor to fair in subsoil; fair to good in substiatum. Poor in subsoil; poor to fair in substratum. Poor in subsoil; poor to fair in substratum. Poor Poor. Poor. Poor to fair in subsoil; fair to good in substratum. High susceptibility to frost heave; seepage occurs in cuts in many places. Medium to high sus- ceptibility to frost heave; some aieas are flooded after heavy rains. High susceptibility to frost heave; in places subject to flooding caused by runoff from adjacent soils; plastic sub- soil. Seasonal high water table; high susceptibility to frost heave; plastic subsoil. Seasonal high water table; moderate sus- ceptibility to frost heave; plastic sub- soil. Subject to flooding; high susceptibility to frost heave; sea- sonal high water table. Seasonal high water table; high suscepti- bility to frost heave; plastic subsoil in places. Moderate susceptibility to frost heave; cuts anrl fills needed. All features favorable. . Topography generally not suitable for small ponds; soils underlain by strati- fied material; possible seepage. Topography generally not suitable for small pond Poor drainage; suitable for dug ponds; seasonal high water table. Shght limitation for dug ponds. In places underlain by coarse-textured ma- terial. Slight limitation for dug ponds. In many places under- lain by very perme- able strata; topog- raphy generally not favorable. MONTGOMERY COUNTY, ILLINOIS 73 engineering properties of soils Soil features affecting suitability for engineering practices — Continued Farm ponds — Con. Embankments Agricultural drainage Irrigation Terraces and diversions Grassed waterways Degree of limitations for septic tank dis- posal field All features favorable.. All features favorable- Fair stability and compaction charac- teristics; high com- pressibility. Fair stability and compaction charac- teristics; high com- pressibility. Unfavorable topogra- phy; fair compaction characteristics; good stability; high com- pressibility. Poor stability and compaction charac- teristics; poor re- sistance to piping; high content of or- ganic matter. Unfavorable topogra- phy; fair compaction characteristics ; good stability; high com- pressibility. Subsoil has fair com- paction characteris- tics and stability; substratum more desirable. Natural drainage ade- quate. Natural drainage ade- quate. Soil has gentle slopes but often remains wet after rains; tile drains not usually installed, because of slow permeability of soil material. Open ditches needed in many places to remove surface water; tile drains not used, because of slow permeabil- ity of soil material. Drainage needed in many places; tile drains function satis- factorily. Additional drainage needed in most places; tile drains function satisfac- torily if an outlet is available; protection from flooding is desirable. Open ditches needed to remove surface water in many areas; tile drains not used, because of slow permeability of subsoil. Natural drainage ade- quate. Slow intake rate; many areas are sloping. Moderate intake rate. Slow permeabil- ity; slow in- take rate; poor natural drain- age. Slow or very slow perme- ability; slow intake rate; poor natural drainage. Moderate intake rate. Flooded at times; poor natural drainage; mod- erate intake rate. Slow permeability; slow intake rate; poor natural drainage. Moderate intake rate; many areas sloping. No major fea- tures that limit construc- tion. If topography is favorable, no major features limit construc- tion. Practice not ap- plicable. Practice not ap- plicable. Practice not ap- plicable. Practice not ap- plicable. Strong slopes common. Practice not ap- plicable. No major features that limit con- struction. No major features that limit con- struction. No major fea- tures that limit construc- tion. No major features tliat limit con- struction. No major features that limit con- struction. No major features that limit con- struction. No major features that limit con- struction. No major features that limit con- struction. Severe; moderately slow permeability; seasonal high water table; sloping. Slight. Severe; slow perme- ability; seasonal high water table. Severe; slow or very slow permeabil- ity; seasonal high water table. Severe; moderately slow permeability; seasonal high water table. Severe; subject to flooding; seasonal high water table. Severe; slow perme- ability; seasonal high water table. Slight for 128B; permeability is adequate, but 128C, 128C2, and 1 28 D have mod- erate limitations because of slope. 74 SOIL SURVEY Table 8. — Interpretations of Soil series and map symbols Suitability as a source of- Topsoil Sand or gravel Highway sub- grade material Soil features affecting suitability for engineering practices Highway location Farm ponds Reservoir area Ebbert (48). Harrison (127A, 127B, 127B2, 127C, 127C2) Harvel (252). Hennepiii Herrick (46, 995) For interpretations for the Fiasa soil in 995, refer to the Piasa series. Hickory (8D, 8D2, 8D3, 8E, 8E2, 8E3, 8F, 8G, 997F, 997G, 998F). For interpretations for the Hennepin soils in 997 F and 997 G, refer to the Hen- nepin series; for interpretations for the Negley soil in 998 F, refer to the Neglev series. Hosmer (21 4B, 21 4C, 214C2, 214C3. 214D2. 214D3). Good to a depth of 12 inches; poor below that depth. Good to a depth of 12 inches; fair to a depth of .30 inches. Fair. Not suited. Poor. Not suited - Poor- Not suited. Poor; in most places contains small stones; surface layer generally thin, and slopes are steep. Good to a depth of 12 inches. Poor; surface layer generally thin, and some slopes are steep. Good to fair in surface layer; 214C3 and 214D3 are severely eroded ana low in con- tent of organic matter. Not suited. Not suited. Not suited. Poor. Fair to good. Poor. Not suited. Subsoil fair; substratum fair to good. Poor to fair. High susceptibility to frost heave; seasonal high water table; plastic subsoil. Moderate suscepti- bility to frost heave. High susceptibility to frost heave; seasonal high water table; flooding in places as the result of runoff from adjacent soils. Slopes are steep; many cuts and fills needed; some seepage in deep cuts. High susceptibility to frost heave; seasonal high water table; plastic subsoil. Slopes are steep; many cuts and fills needed; some seepage in deep cuts. Slight limitation for dug ponds. Moderate susceptibility to frost heave; many cuts and fills needed; slopes are erodible; possible seepage in road cuts. Moderate limitations for dug ponds ; excessive perme- ability and low water table. Slight limitation for dug ponds. A few pockets of gravel ; otherwise favorable. Slight limitation for dug ponds. All features favorable, except in the Negley soil of 998 F, which has underlying ma- terial that is coarse textured and rapidly permeable. All features favorable. . MONTGOMERY COUNTY, ILLINOIS 75 engineering properties of soils — Continued Soil features affecting suitability for engineering practices — Continued Degree of limitations for septic tank dis- Farm ponds — Con. posal field Agricultural drainage Irrigation Terraces and diversions Grassed waterways Embankments Topography not well Open ditches needed Slow permeability; Practice not ap- No major features Severe; slow perme- suited; fair to poor for drainage in most slow intake rate; plicable. that limit con- ability; seasonal stability and com- areas; t'le systems poor natural struction. high water table. paction characteris- remove water more drainage. tics; high compressi- slowly than in most bility if subsoil is soils because of the compacted. slow permeability of the subsoil. Subsoil has fair to poor Natural drainage ade- Most areas slop- No major features No major features Slight for 127 A. stability and com- quate in most areas; ing; moderate that limit con- that limit con- 127B. and 127B2 paction characteris- small, low areas can intake rate. struction. struction. moderate for 127C tics; high compres- be improved by tile and 127C2 because sibility where the diainage. of slope; perme- soil material is com- ability is adequate. pacted would be more desirable. Topography not well Additional drainage Moderate intake Practice not No major features Severe; seasonal high suited; fair to poor needed in most rate; poor na- applicable. that limit con- water table; mod- stability and com- areas ; in many places tural drainage. struction. erately slow to paction character- tile drains are diffi- moderate perme- istics; high compres- cult to install be- ability. sibility if compacted. cause of long dis- tance to an adequate outlet. All features favorable. _ Natural drainage ade- Steep slopes Too steep for Steep slopes com- Severe; permeability quate. terraces. mon; cover of plants difficult to establish. is adequate, but steep slopes make installation of disposal fields difficult. Topography not well Additional drainage by Moderate intake Practice not No major features Severe; moderately suited ; fair to poor tile drains and sur- rate; moderately appU cable. that limit con- slow permeability; stability and com- face ditches needed slow permea- struction. seasonal high paction character- in most areas; mod- bility. water table. istics; high com- erately slow perme- pressibility if com- ability. pacted . All features favorable, Natural drainage ade- Steep slopes Most slopes too Steep slopes com- Permeability is ade- except in the Negley quate. steep for ter- mon; cover of quate, but steep soil of 998 F, which races. plants difficult slopes make instal- has underlying ma- to estabhsh. lation of disposal terial that is coarse fields difficult; 8D, textured and rapidly 8D2, and 8D3 have permeable. moderate limita- tions caused by slope; 8E, 8E2, 8E3, 8F, 8G. 997F, 997 G, and 998 F have severe limi- tations caused by slope. Subsoil has fair sta- Natural drainage ade- Shallow rooting Difficult to obtain Difficult to obtain Severe; slow per- bility and compac- quate. depth; slow good growth of a good cover of meability in tion characteristics; permeability; crops in terrace sod where fragi- fragipan; instal- all features favorable slow intake channel. pan is exposed. lation of disposal in substratum. rate; soils are sloping. fields difficult on the steeper slopes. 76 SOIL SURVEY Table 8. — Interpretations oj Soil series and map symbols Suitability as a source of — Topsoil Sand or gravel Highway sub- grade material Soil features affecting suitability for engineering practices Highway location Farm ponds Reservoir area Hoyleton (3A, 3B, 3B2, 992 B). For interpi etations for Tamalco soil in 992B, refer to the Tamalco series. Huey Ipava (43). Landes (304).... Lawson (451). Negley. Nokomis (586). Oconee (113A, 113B, 113B2, 113C, 113C2, 994A. 994B, 994B2, 994C2). For interpretations for the Tamalco soil in 994A, 994B, 994B2, and 994C2, refer to the Tamalco series. Good to fair in surface layer. Poor; areas are small and con- tain slickspots; soil material low in fertility; some of it con- tains excessive sodium. Good in surface layer. Good to a depth of 12 inches; somewhat sandy. Good to a depth of 24 inches. Not suited. Fair in surface layer; some slopes are steep. Good to a depth of 24 inches. Good in sui'face layer only. Not suited. Subsoil poor; substratum poor to fair. Poor. Not suited - Poor. Possible source of sand and silt mixtures. Good to fair Not suited. Good source of mixed sand and gravel below a depth of 8 to 10 feet. Poor. Subsoil fair to poor; very good to good below a depth of 4 feet. Not suited. Not suited. Fair to poor- Poor. High susceptibility to frost heave; seasonal high water table. Seasonal high water table; high suscepti- bility to frost heave. High susceptibility to frost heave; un- stable when wet; seasonal liigh water table. Subject to flooding Subject to flooding; seasonal high water table; moderate susceptibility to frost heave. Steep slopes; many cuts and fills needed; some seepage in deep cuts. Subject to flooding; seasonal high water table; moderate sus- ceptibility to frost heave. High susceptibility to frost heave; sea- sonal high water table; plastic sub- soil. All features favorable.. Poor drainage; high water table; suitable for dug ponds; in places water is cloudy because soil particles remain in suspension. Moderate limitations for dug ponds; slight seepage. Excessive seepage; subject to flooding. Excessive seepage; subject to flooding. Coarse gravel permits excessive seepage. Excessive seepage- All features favorable. MONTGOMERY COUNTY, ILLINOIS 77 engineering properties of soils — Continued Soil features affecting suitability for engineering practices — Continued Farm ponds — Con. Embankments Agricultural drainage Irrigation Terraces and diversions Grassed waterways Degree of limitations for septic tank dis- posal field Subsoil has fair sta- bility and compac- tion characteristics; all features favor- able in substratum. Fair stability and compaction charac- teristics; high compressibility. Fair to poor stability and compaction characteristics. Unfavorable topog- raphy; rapid permeability; poor resistance to piping. Unfavorable topog- raphy; poor stability and compaction characteristics; poor resistance to ijiping. All features favorable in subsoil; in places substratum is too coarse textured and permeable for an embankment. Unfavorable topogra- phy; poor stability and compaction characteristics; poor resistance to piping. Fair stability and com- paction character- istics; high com- pressibility if com- pacted. Additional drainage needed in some areas; tile drains not satisfactory, because of slow permeability of subsoil. Open ditches needed in many places to remove surface water; tile drains not used, because of very slow perme- ability of soil material. Additional drainage needed; tile drains function satis- factorily. Additional drainage needed in some areas; open ditch drainage satisfac- tory; protection from flooding desirable. Additional drainage needed; tile drains function satisfac- torily if an outlet is available ; protection from flooding desirable. Natural drainage adequate. Additional drainage needed in some areas; tile drains function satisfac- torily. Additional drainage needed in some areas; tile drains not satisfactory, because of slow permeability of subsoil. Slow intake rate; slow permea- bility; in some places soils are gently sloping. Very slow perme- ability; slow intake rate; poor natural drainage; sub- soil highly saturated with sodium. Moderate intake rate. Subject to flood- ing in places, but has rapid intake rate and permeability ; moderate to low water-holding capacity. Subject to flood- ing; moderate intake rate. Steep slopes. Subject to flood- ing; moderate intake rate. Slow intake rate; slow permea- bility; most areas are sloping. Terrace channel likely to remain wet, and only medium growth of crops is obtained. Practice not applicable. Practice not applicable. Practice not applicable. Practice not applicable. Most slopes too steep for terraces. Not needed in most places. Terrace channels likely to remain wet, and only moderate growth of crops is obtained. No major features that limit construction. Difficult to estab- lish grass on alkaline subsoil; in ])laces need to blanket with better soil ma- terial or give other special treatment. No major features that limit construction. No major features that limit construction. No major features that limit construction. Steejj slopes common; cover of plants diffi- cult to estab- lish in channel of waterway. No major features that limit con- struction. No major features that limit con- struction. Severe; slow perme- ability; high water table. Severe; very slow permeability ; seasonal high water table. Moderate; seasonal high water table. Severe; subject to flooding. Severe; subject to flooding; seasonal high water table. Severe; permeability is adequate, but steep slopes make installation of disposal fields difficult; under- lying coarse- textured material allows contamina- tion of nearby water supplies. Moderate; seasonal liigh water table; subject to occa- sional flooding. Severe; slow permea- bility; seasonal liigh water table. 78 SOIL SURVEY Tablk 8. — Interpretations oj Suitability as a source of — Soil features affecting suitability for engineering practices Soil series and map symbols Topsoil Sand or gravel Highway sub- grade material Highway location Farm ponds Reservoir area O'Fallon (114B) _._ Good in surface layer only. Not suited Poor to fair Moderate suscepti- bility to frost heave. Slight limitations Pana (256C2, 256D2) Good to a depth of 12 inches; somewhat sandy in places. Possible source of gravel; sand mixtures are below a depth of about 6 feet. Subsoil good; substratum very good. Sloping; many cuts and fills needed. Excessive seepage because of coarse- textured material in the profile and under- lying these soils. Piasa Poor; areas are small; some areas contain excessive sodium. Not suited Poor Seasonal higli water table; high sus- ceptibility to frost heave; plastic sub- soil. Sliglit limitation for dug ponds: water may be cloudy be- cause soil particles remain in suspension. Pike (583A, 583B, 583C, 583C2, 583D2). Good in surface layer. Possible source of gravel and sand mixtures below a depth of about 5 feet. Subsoil poor; substratum fair to poor. Sloping; cuts and fills needed; moderate susceptibility to frost heave. Excessive seepage in underlying material; coarse textured. Racoon (109) Fair to a depth of 24 inches. Not suited Poor - _ _ Moderate susceptibility to frost heave; sea- sonal high water table; susceptible to flooding after heavy rains. Slight limitation for dug ponds; subject to flooding. Radford (74) Good to a cleptli of 12 inches. Not suited Poor Subject to flooding; high susceptibility to frost heave; seasonal high water table. In places underlain by coarse-textured mate- rial; subject to flooding. Shiloh (138, 138 + ) 1.38 is fair to poor; 1 38+ is good to a depth of 10 to 12 inches. Not suited Poor High susceptibility to frost heave; sea- sonal high water table; in places sub- ject to flooding caused by runoff from adjacent higher soils. Slight limitations for dug ponds. Sicily (258B, 258C2) Good in surface layer. Not suited Poor Moderate susceptibility to frost heave. All features favorable. _ ( MONTGOMERY COUNTY, ILLINOIS 79 engineeriny i^roperties of soils — Continued Soil features affecting suitability for engineering practices — Continued Degree of limitations for septic tank dis- Farm ponds — Con. posal field Agricultural drainage Irrigation Terraces and diversions Grassed waterways Embankments Subsoil has fair sta- Natural drainage ade- ^Moderate rooting Difficult to obtain Cover Oi plants Severe; fragipan bility and compac- quate. depth; slow good growth of difficult to es- slowly permeable. tion characteristics; permeability; crops in terrace tablish because all features favor- slow intake channel. of the fragipan. able in substratum. rate. Subsoil has no un- Natural diainage ade- Strong slopes No major features No major features Moderate, because favorable character- quate. that limit con- that limit con- slopes are some- istics; substratum struction. struction. what steep for in- is rapidly permeable stalling disposal and subject to fields; fast move- seepage. ment of water in coarse-textured material can con- taminate the water supply. Unfavorable topogra- Open ditches needed Very slow permea- Practice not ap- Difficult to estab- Severe; very slow phy; fair compac- to remove surface bility; slow in- plicable. lish grass on permeability; sea- tion characteristics; water in many take rate; poor alkaline subsoil; sonal high water good stability; high areas; tile drains not natural drain- in places need table. compressibility. used, because of age; subsoil to blanket with very slow permea- saturated with better soil mate- bility of subsoil. sodium. rial or give other special ti eatment. Subsoil has fair sta- Natural drainage ade- Strong slopes in No major features No major features Permeability is ade- bility and compac- quate. most places; that limit con- that limit con- quate; slope is a tion characteristics; slow water in- struction. struction. slightly limiting all features favor- take rate. factor 'in 583 A and able in substratum. - 583 B, and a mod- erately limiting factor in 583C, 583C2, and 583 D2. Poor stability and com- Additional drainage Slow intake rate; Practice not ap- No major features Severe; slow permea- paction characteris- needed in most poor natural plicable. that limit con- bility; subject to tics; poor resistance places; open ditches drainage; slow struction. occasional flooding; to piping in upper- used because of the permeability; in seasonal high most 2 feet. slow permeability of the subsoil. places subject to occasional flood- ing. water table. Poor stability and com- Additional drainage Subject to flood- Practice not ap- No major features Severe; subject to paction characteris- generally needed; ing; moderate plicable. that limit con- flooding; seasonal tics; poor resistance tile drains function intake rate. struction. high water table. to piping. satisfactorily ; protec- tion from flooding is desirable. Fair stability and poor Additional drainage Moderately slow Practice not ap- No major features Severe; moderately compaction charac- needed; tile drains to slow permea- plicable. that limit con- slow to slow per- teristics; higli function satisfacto- bility; in places struction. meability ; seasonal compressibility if rily if an adequate receives runoff high water table. compacted. outlet is available; in places receives runoff from higher lying soils. from adjacent higher lying soils. Subsoil has fair stability Natural drainage Moderate slopes; No major features No major features Permeability is ade- and compaction char- adequate. moderate intake that limit con- that limit con- quate; limitations acteristics; all fea- rate. struction. struction. caused bv slope are tures favorable in slight in 258 B and substratum. moderate in 258C2. 80 SOIL SURVEY Table 8. — Interpretations oj Soil series and map symbols Starks(132). Stoy (164A, 164E Tamalco (581 B, 581 B2, 581C2). Terril (5878). Velma (250C, 250C2, 250D, 250D2, 250E, 996C2, 996D2). For interpretations for Walshville soils in 996C2 and 996 D 2, refer to the Walshville series. Virden (50). Walshville. Weir (155). Suitability as a source of — ■ Topsoil Good in surface layer. Fair in surface layer. Poor; surface layer is thin and in places soil material con- tains excessive sodium. Good to a depth of 24 inches; fair below that depth. Fair in surface layer. Sand or gravel Not suited. Not suited- Highway sub- grade material Poor above a depth of 4 feet; fair be- low that depth. Poor to fair Fair in surface layer; season- ally wet; some- what clayey. Poor; occurs in small areas; has thin surface layer; in places soil material contains exces- sive sodium. Fair in surface layer; poorly drained sites. Not suited. Not suited- Not suited- Not suited- Not suited. Not suited- Poor. Poor to fair- Subsoil fair; substratum fair to good. Poor- Poor. Poor- Soil features affecting suitability for engineering practices Highway location Moderate susceptibility to frost heave; sea- sonal high water table; in places sub- ject to flooding after heavy rains. High susceptibility to frost heave; seasonal high water table. High susceptibility to frost heave; difficult to grow cover of plants on the sides of cuts. Medium to high sus- ceptibility to frost heave; subject to flooding during times of extremely high water. Sloping; many cuts and fills necessary; in many places seepage causes difficulty in cuts. High susceptibility to frost heave; seasonal high water table; plastic subsoil in places. Moderate suscepti- bility to frost heave; plastic subsoil; many cuts and fills needed; seepage causes difficulty in cuts; difficult to grow grass on the sides of cuts. High susceptibility to frost heave; seasonal high water table; plastic subsoil. Farm ponds Resevoir area Topography generally not sutable for small ponds. All features favorable. Water may be cloudy because soil particles remain in suspension, In most places topog- raphy is not suitable for small ponds. Thin layers of gravelly material allow seepage. Moderate limitations for dug ponds. Water may be cloudy because of soU particles that re- main in suspension. Slight limitations for dug ponds. MONTGOMERY COUNTY, ILLINOIS 81 engineering projjerfies < t/ soils — Continued Soil features affecting suitability for engineering pjactices — Continued Degree of limitations for septic tank dis- Farm ponds — Con. posal field Agricultural drainage Irrigation Terraces and diversions Grassed waterways Embankments Fair stability and com- Additional drainage Slow intake rate No major liiniting No major features Moderate ; moderate paction characteris- needed in some factors, but that limit con- to moderately tics; material in sub- areas; surface terraces and struction. slow permeability; stratum subject to ditches usually used. diversions gen- seasonal high piping. erally not needed. water table. Subsoil has fair stability Additional drainage Slow intake rate Terrace channel No major features Severe; slow permea- and compaction char- needed in some and slow per- tends to remain that limit con- bility; seasonal acteristics; all features areas; tile drains not meability; some wet, and only struction. high water table. favorable in sub- satisfactory, be- areas are gently moderate growth stratum. cause of slow per- meability of subsoil. sloping. of crops is obtained. Subsoil has fair stability Natural drainage Slow intake rate; Difficult to obtain Difficult to estab- Severe; very slow and compaction char- adequate. very slow per- good growth of lish grass on al- permeability. acteristics; high com- meability; sub- crops in chan- kaline subsoil; pressibility if com- soil saturated nel because sub- need to blanket pacted; all features with sodium. soil has un- area with better favorable in sub- favorable char- soil material in stratum. acteristics. places or to give other special treatment. All features favorable. . Natural drainage Moderate intake No major featiu'es No major limiting Slight. adequate. rate; gently sloping. that limit con- struction. factors. Fair stability and Natural drainage Strong slopes No major features No major features Permeability is ade- compaction charac- adequate. that limit that limit con- quate; limitations teristics; high com- construction. struction except caused by slope pressibility if that some slopes are moderate in compacted. are steep. 250C, 250C2, 250D, 250D2, 996C2, and 996 D2; they are severe in 250E. Unfavorable topog- Additional drainage Aloderately slow Practice not No major features Severe; moderately raphy; fair stability needed; tile drains permeability ; applicable. that limit slow permeability; and compaction supply adequate poor natural construction. seasonal high characteristics; high drainage. drainage. water table. compressibility if compacted. Fair stability and Natural drainage Strong slopes; Difficult to obtain Difficult to estab- Severe; slow perme- compaction charac- adequate. slow intake good growth of lish grass on ability; slopes teristics; high rate; slow crops in channel alkaline subsoil; are somewhat compressibility if permeability; because subsoil need to blanket steep for installing compacted. subsoil satu- has unfavorable area with better disposal fields. rated with characteristics. soil material in sodium. places or to give other special treatment. Unfavorable topog- Additional surface Slow intake rate; Practice not No major features Severe; slow perme- raphy; fair stability drainage needed in slow perme- applicable. that limit ability; high and compaction some areas; open ability; poor construction. water table. characteristics; high ditches installed in natural compressibility if most places, as tile drainage. compacted. will not function because of slow permeability of subsoil. 82 SOIL SURVEY classified as A-7 and CH have high sliriiilc-swell potential. Clean sands and gravel, which are structureless (single grain), and sands and gravel that contain a small amount of nonplastic to slightly plastic fines, have low shrinlv- swcll potential, as does most other nonplastic to slightly plastic soil material. Some soils tend to cause corrosion of unti'eated steel undergTOimd conduits and pipes. The corrosion potential is influenced by the soil texture, by the amount and type of clay in the soil, by the acidity of the soil, by the amount and kind of soluble salts present, by the content of moisture, and by the kind of material from which the conduit is made. Table 7 gives estimated ratings of kigli^ moderate^ and low for the soil horizons in which conduits are likely to be buried. Because a conduit would normally not be buried in the surface layer, ratings are not given for that layer. Engineering interpretations of the soils Table 8 indicates suitability of the soils as a source of topsoil, sand or gravel, and subgrade matei'ial for high- ways. It also names specific features of the soils that can affect the selection, design, and construction of various engineering works. These features are evaluated from test data and from field experience. A particular feature of a soil can be helpful in one kind of engineering work but a hindrance in another. A highly permeable substratum, for example, is undesirable as a site for a pond, but it could be advantageous where artificial drainage is needed. Highways and other stx'uctures can be severely damaged by the shrinking and swelling of the miderlyhig soils. Susceptibility to frost heave is an important factor in rating suitability for the location of a highway. A high water table and susceptibility to flooding are other impor- tant factors in choosing a suitable location. Table 8 also shows soil features that affect the installa- tion of stri;ctures used for managing water. In Montgom- ery County the most suitable structures for managing water are farm ponds, diversions, grassed waterways, sys- tems that provide artificial drainage, and structures that help to control erosion. The site for a pond must be selected Avith care. Table 8 names soils that are not suitable or tliat are of doubtful quality for a pond. Slowly permeable soils are the most suitable for a resei-voir area, and they generally can be used in the eml^ankment. The appraisals of suitability of the soils for embankments are based on the permeability, sup- porting strength, and ease of compaction of the soil ma- terial and on the stability of this mater'ial in slopes. Soils that have a high content of silt make suitable mate- rial for embankments only when special effort is made to obtain a high degree of compaction. Unless these silty soils are well compacted, embankments made of them are likely to be porous, and they allow water to seep thi'ough them in a i-eJatively short time. As a result, the soil ma- terial on the downstream side of the embankment becomes wet and can slide out of jDlace. Piping is another major hazard in many silty and sandy soils. Wliere the rate of seepage through the embankment is rapid, the finer par- ticles of soil material are washed out and holes that resem- ble tunnels are left. These holes can eventually destroy the embankment. Artificial drainage is needed in many of the nearly level soils. Drainage is accomplished by installing tile drains or shallow surface ditches and by providing deep outlet ditches. Tlie drainage system should be planned by an en- gineer experienced in that kind of work. Tile drains are not effective in all soils that need supple- mental drainage. They are not satisfactory, for example, in soils that contain a claypan through which water moves very slowly. Where tile drams are installed, an adequate outlet is essential. Sites for an outlet are not available in some areas of bottom lands along streams. Shallow surface ditches are well suited to use for drain- ing the level or nearly level soils that contain a claypan. These drains consist of a wide, shallow channel that can be crossed easily by farm machinery. They can be used in com- bination with tile drains or as a separate dramage system. In many locations the efficiency of a surface drainage sys- tem can be improved by land smoothing. Land smoothing consists of removing small ridges and high spots, and of filling shallow low areas. This leaves a more nearly uni- form field slope and lets water move quickly into the drain- age chamiel. Deep outlet ditches generally receive water floAving from tile, surface drainage channels, and other outlet ditches. Generally, it is necessary to construct the ditch across two or more adjacent farms so that an adequate outlet can be reached. The rapid growth of Avoody A^egetation in outlet ditclies necessitates regular maintenance to keep the ditches operating effectively. In planning and c-onstructuig an outlet ditch, it is necessary to detennine the capacities of bridges and culverts and the need for structures to lower the surface flow into the outlet ditch without causing ero- sion. Caving of the banks can be caused by underlying- layers of sand. Table 8 names soil features that affect suitability for ir- rigation. Among the features that affect suitability are intake rate, soil penneability, slope, natural drainage, and susceptibility to flooding. Also important is the presence of sodimn salts m the subsoil. Terraces and diversions help to control erosion in slop- ing soils. In many parts of the county, terraces are not practical, howeA^er, because the slopes are steep or irregular. Diversions generally can be used if a stabilized outlet is aA^ailable. Grassed waterways serve as an outlet for diA^ersions or terraces. They also help to prevent gullying in natural watercourses. The channels have to be properly shaped and should have a dense cover of sod. Ordinarily, establishing A^egetation in a Avaterway is difficult if the soils are shallow or steep. A good mulch, liberal applications of fertilizer, and normal tillage are helpful. Ratings of slight, moderate, and severe are given in table 8 to shoAv the degree of limitation for septic tank disposal fields. Among the featin*es that make a site un- favorable for the construction of a disposal field for effluent from a septic tank are moderately sIoav or sloAAcr permea- bility, flooding, a seasonal high water table, and steep slopes. Some soils that are formed in or are underlain by coarse-textured, rapidly penneable material absorb effluent from septic tank disposal fields so rapidly that the effluent reaches miderground water supplies before it is completely filtered. Where this hazard of contamination is a possibil- ity, it is noted in table 8. MONTGOMERY COUNTY, ILLINOIS 83 Genesis, Classification, and Morphology of Soils This sectioii has four main parts. The first gives facts about the formation, or genesis, of soils, the second de- scribes process of soil development, and the third gives facts about the genesis of selected horizons. The fourth briefly discusses the classification of soils under the system currently used by the National Cooperative Soil Survey and classifies the soils according to that system and the sys- tem earlier used by soil scientists. Factors of Soil Formation Soil is foi-med by weathering and other processes that act on parent material. The characteristics of the soil at any given point depend upon the parent material, x^lant and animal life, climate, time, and topography and drain- age. Four of these factors have been important in causing diiferences among the soils in Montgomery County. The fifth, climate, apparently has not caused major diti'erences in the soils, because the climate is practically uniform thi'oughout the county. The climate of INIontgomery County is discussed in the section "Additional Facts iS^bout the County." Parent material The soils of Montgomery County have formed in three main kinds of parent material, namely loess, glacial drift, and silty and loamy alluvimn. None of the soils have formed in parent material derived from the underlying- bedrock. In the following paragraphs, these main kinds of parent material and the bedrock are described and the types of clay minerals in the soils are briefly discussed. Loess. — Loess is the most important kind of parent material from Avhich the soils in the county Avei'e derived and is the material from -which the soils of many of the series have formed. It was deposited by wind during the Wisconsin glacial age. Loess consists mostly of silt-sized particles, but it contains some clay. It was blown mainly from the valleys of the Illinois and Mississippi Rivers and was deposited in the areas whei'e it now lies. The deposit of loess is thickest in the northwestern part of the county, where it is about 7 feet thick. It is thinnest on the upland plain in the southeastern part of the county, where it is only about 4 feet thick. When the loess was deposited, it was calcareous, was nearly unifonn in characteristics, and consisted of rela- tively unweathered particles of rock. Smce that time, the processes of soil development have acted to change it to soils that are decidely different. Glacial drift. — This is the second most important of the parent materials in the county. It lies beneath the loess and is of Illinoian age. The drift consists of Jacksonville till in the northern part of the county. Men don (Payson) till in the western part, and a belt of ridge drift in the eastern part that marked the contact of the Saginaw lobe with the Lake Michigan lobe (!?<§). According to Leigh ton and Brophy (17), the moulin kames, crevasse ridges, and subcrevasse channels on and in the land surface in this area indicate wastage of the glacier by stagnation. The thickness of the drift ranges from more than 100 feet, over valleys of buried bedrock or in morainal areas, to only a thin covering over bedrock highs, such as those north of Nokomis in the general area where limestone is quarried. The layer of drift is also thin in areas where modern streams are cutting into the Ijedrock, as in the areas east of Litchfield and west of Panama. Where the glacial drift consists of a mixture of many kinds of unsorted rocks of various sizes (pebbles, sands, silts, and clays), which were deposited by ice, it is known as glacial till. Glacial till is tlie j^ai-ent material of the Blair, Hennepin, Hickory, Velma, and Walshville soils. Unweathered, unleached till lies beloAv the profiles of soils that developed in the till. In most places the texture of the till is loam, but it is sandy loam in places. The till con- tains some calcium and magnesium carbonates but does not contain large amounts. Stratified drift deposited by glacial melt water contains much more sand and gravel than the glacial till, and it is called glacial outwash or coarse-textured drift. The Pana and Negley soils have developed in this coarser textured matei'ial. The unweathered, unleached outwash beneath the Pana and Negley profiles consists mainly of sand and rounded pebbles that are mostly less than 2 inches in dia- meter. In some places this material is finer textured, how- ever, and consists of sand and loamy sand. The coarse- textured drift is used locally for roads but is too sandy to be well suited to that use. Bedrock. — Below the drift is bedrock of Pennsylvanian age. The elevation at which the bedrock occurs ranges from about 650 feet above sea level, in a few spots in the north- ern part of the county, to about 400 feet along the southern border of the county, near Donnellson. The point where the elevation is only 400 feet is in the buried valley of the ancestral Shoal Creek (9) . Montgomeiy County is in the southwestern part of the Pennsylvanian basin in which thick sedimentary rocks occur. These rocks are primarily shales, sandstones, lime- stones, and coals that were deposited in a cyclical pattern. Both the upper and middle groups of Pennsylvanian for- mations occur extensively in this county (16). The middle group is especially important because in that group are most of the mapped minable coal reserves in Illinois. Rocks of Pennsylvanian age are near the surface or at the surface in some places, though they have not supplied the parent material for any of the soils. Alluvium.- — Silty and loamy alluvium is the parent ma- terial of the soils in the valleys of the major streams. Most of this material has a texture of silt loam or loam, but the texture is silty clay loam in a few places. The alluvium has been deposited over a long period of time that possibly extended from the end of the period when loess was laid down to the present time. Clai/ minerals. — The type of clay minerals m the soil material is related to the kind of parent material. Studies made by Frye, Glass, and Willman (7) indicate that the 23rincipal clay minerals in the soils of this county that developed in loess are montmorillonite and vermiculite, but that illite is the principal clay mineral in the soils that developed in glacial till. Because alluvium is derived both from loess and glacial till, we can expect that the clay minerals in soils that developed in this material con- sist of a mixture of montmorillonite and illite. 84 SOIL SURVEY Plant and animal life Plants and animals have contributed much to the de- velopment of soils in Montgomery County. Plants, throupli their growth and partial decomposition, ai"e responsible for the organic matter in soils. Animals are responsible for burrowing in the soil material and mixing it. Many differences in the soils of this county have been caused by differences in the kind of vegetation that has grown in various areas since the soil material was de- posited. The thickness and dark color of the surface layer of Mollisols, for example, was caused by black organic matter, which, in turn, resulted from the decomposition of herbaceous plants that grew in the prairie areas of the county. These soils have a high content of organic matter and organic carbon (fig. 1.')), and as a result, they are high m nitrogen-supplying capacity. The soils that have developed under forest, for example the Hosmer, Hickory, and Pike, have a thin, dark-colored surface layer that has resulted fi-om the mixing of dead leaves with the mineral surface soil. The plow layer of those soils is comparatively light colored (fig. 14). It con- tains less organic matter than the surface layer of the dark-colored soils. A land survey prepared in 1818, liefore white persons settled in the area, shows the distribution of tracts under grass and of tracts under forest in that year. It shows that trees were growing on some of the dai'k-colored soils at that time, indicating that forests were invading the areas of prairie. The survey also shows that grass covered some areas of moderately dark colored soils, indicating that the forest cover had receded in some areas. Animals have influenced the development of soils. The Harvel soils, for example, appear to consist principally of crayfish burrows that have been filled with mixed soil ma- terial. Because of this mixing, the Plan^l soils have a sub- soil that is less uniform in characteristics than the subsoils of the Virden and Shiloh soils, which have not been mixed extensively by burrowing crayfish. The Pana soils appear to have developed in mixed loess and gravelly glacial drift. This is apparently true because it is doubtful if soils that contain as many fine particles as the Pana soils could have developed entirely from coarse- textured material, such as drift. It is also difficult to under- stand how erosion could have removed all of the loess cap in areas of Pana soils, because those soils generally occur on the summit of morainal ridges. It appears much more probable that the Pana soils have developed in loess and gravelly drift mixed by gromidhogs or other burrowing animals. Earthworms continually mix the soil material, and their burrows terminate several feet below the surface in a spherical void. Many of these burrows are lined with dark- colored clay, which indicates that they are features of the soil that have been used over a long period of time. Bacteria and fungi have also contributed much to the development of organic matter in soils. It is believed that bacteria were the more important organisms that con- tributed to the deconiposition of herbaceous material in the prairie areas, and that fungi were more important in causmg the decomposition of leaves, tree roots, and wood. Topography and soil drainage All of ^Montgomery County is in the Springfield Plain of the Central Lowland Province (18) . The county consists mainly of a nearly level plain in which streams have cut steep-walled valleys. A large area of ridged drift, consist- ing of rolling moraines and kames, however, extends from the northeastern corner of the county soiithwestward towards Hillsboro and south to a point beyond the county line. These rolling moraines and kames are interspersed with small areas of plains, some of which are basins of old lakes. One of these former lake basins lies north of Butler. Its center is in the northwestern part of section 10, T. 9 N., R.4W. Most of the rolling morainal areas in the eastern part of the county are (i50 to KiO feet above sea level, but the elevation at Bald Knol) is TtU feet. The elevation of most of the gently slo])ing areas of ujilands is 600 to 625 feet, but that in the stream vallev'S is somewhat lower. The lowest elevation, approximately 503 feet above sea leA'el, is at a point where Shoal Creek leaves the south side of the county, near Panama. Elevations at other points in the county are Hillsboro, 630 feet; Nokomis, 670 feet, and Farmersville, 643 feet. Topography influences soil drainage, and soil drainage, in turn, greatly affects the color of the soils. Soils that have developed under good drainage have a subsoil that is uniforn^ly brown in color, but Virden, Piasa, and similar soils that have developed under poor drainage have a gray- ish color. Soils that have developed where the drainage is intermediate between good and poor have a subsoil that is mottled with gray and brown. The grayish colors persist. HERRICK '0 I 2.0 PERCENT ORGANIC CARBON 5 25 45 40 PERCENT CLAY«.002mm ) 6,0 pH 8 Figure 13. — Some properties of a selected dark-colored soil. MONTGOMERY COUNTY, ILLINOIS 85 4 88 HOSMER 10 PERCENT ORGANIC 20 CARBON 25 45 40 CLAY(<.002mm) PERCENT Figure 14. — Some properties of selected light-colored soils. even though the drainage is greatly imi^roved by ditches and tile drains. Good drainage, or the lack of it, is also related to the eluviatiou of clay from the A to the B horizons. In the sloping Douglas soils, and in others of the steeper, well- drained soils, the rate at which clay moves downward in the profile is only moderate. In nearly level soils, such as the Herrick. on the other hand, more clay has accumidated than in the Douglas soils, and these soils generally have a more distinct profile than the Douglas soils. The profiles of Virden and other soils that have poor natural drainage show that only a small amount of clay has moved downward in those soils. This is probably be- cause no appreciable amount of water has moved through the profile to carry the fine particles of clay downward. Lack of water movement also explains the dift'erences in reaction between the Virden and Herrick soils. The reac- tion of the Virden soils is about neutral throughout the profile, but the surface layer and the subsoil of the Herrick soils are acid. Time Time is needed for the processes of soil development to exert their influence on the soil profile. Soil age is differ- ent from geologic age in that soil age refers to the period during which the soil material has been weathered, rather than to the date the material was deposited. As an ex- amj)le, the Hennepin soils are considered to be young be- cause their parent material was recently uncovered by valley entrenchment and l)y the widening of stream val- leys by stream! )ank cutting. The oldest soils in the county are those formed in loess, which was deposited during the Wisconsin age, from 10,000 to 60,000 years ago (7).^ Be- cause loess formerly completely covered the county, all the other soils must have developed in material that was uncovered after the loess was deposited and w-as eroded away, and those soils are of more recent age than the ones that developed in loess. Some soils that developed in glacial till are of Late Wis- consin age, but others have developed only recently. Hick- ory soils are typical of the older soils that "formed iii glacial till. Their profile is as well developed and as leached as that of the loess-derived Pike soils, and they ha-\-e accumu- lations of clay in their B horizons that are similar to those in the Pike soils. Hennepin soils are the most recent soils that developed in glacial till. Except that those soils have a thin, dark-colored surface layer that is generally leached of carbonates, those soils lack a well-developed profile. The soils that developed in alluvial deposits are of about the same age as those that developed in glacial till. The Camden and Starks soils, for example, are old enough that they have as distinct B horizons as those in the Hick- ory soils. Lawson soils, on the other hand, are so recent that they do not contain distinct horizons, except for upper horizons that have resulted from some accumulation of organic matter. In this respect their age is comparable to that of the Hennepin soils. The ages of the Nokomis and Terril soils ai-e intermediate between those of the Camden and Starks soils, which have well-developed profiles, and those of the Lawson soils, which have only a slightly de- veloped profile. Processes of Soil Development After the parent material of the soils of Montgomery County was deposited or was uncovered, it was changed by the processes of soil development until it became a dis- tinct kind of soil, or several distinct kinds of soil. These pi'ocesses are the laccumulation of organic matter; disinte- gration of rock; weathering of rock minerals to soluble materials; leaching of i\\ii' soluble materials; movement of clay from the upper horizons to the lower, and accumula- tion of clay in the lower horizons; and movement, oxida- tion, reduction, 'and hydration of iron. jMost of tliese i^rocesses required a long period of time to become 'apparent. The accunndation of organic matter is one of the fii^t changes that can be noticed in a soil. It is influenced by the kind of drainage and the type of vegetation. In soils that formed in alluvium, for example the Lawson soils, accunuilation of organic matter is the most obvious char- acteristic that distinguishes the upper horizons from the lower. Disintegration of rock, especially in some of the granites or other igneous rocks in the glacial till parent material of the Hickory and Velma soils, is a process that begins early in the development of a soil. This process is not important, however, in the development of soils formed in loess and in alluvium. Weathering of some resistant rocks results in clianges in which soluble compounds are released. These soluble compounds then l)ecome plant nuti'ients that are held avail- 86 SOIL SURVEY able to plants. When feldspars are weathered, for example, they slowly release potassium, sodimn, calcimn, magne- simn, and other elements in soluble form, and these ele- ments then become available to j^lants. Also, apatite slowly releases soluble phosphorus, and this phosphorus accumu- lates in the soil. The release of plant nutrients is generally too slow to supply the large amounts of plant nutrients needed for present-day farming, though it is important in the development of soils. Leaching of soluble material takes place in soils, but this process is slow in the Piasa and other alkaline soils. Early in the development of soils, limestone pebbles and rocks are decomposed and some of their weathering prod- ucts are leached away. Water slowly removes the calcium, potassium, magnesium, and other carbonates from the soils. This has happened in the Hickory soils, where leach- ing since the Wisconsin ice age has removed the carbonates to a depth of 4 to 6 feet. This leaching eventually causes a soil to be acid and less productive than other soils that have been less extensively leached. Examples of strongly leached soils are the Hosmer, Stoy, and Weir. Percolating water slowly washes the clay in the upper horizons of a soil downward through the soil pores and deposits it in the subsoil. In Montgomery County this process is most evident in the Cowden, Cisne, and Weir soils. In many places the subsoil of these soils is three times as rich in clay as the surface horizons, as indicated by the content of clay in the profile of the Cowden soils (fig. 15). This process is less evident in the profile of the Herrick soils (see fig. 13) than in the profile of the Cowden soils, and it is also less e\ident in the profile of the Shiloh soils, which have considerable clay in the surface layer and only a slightly larger amount in the upper part of the subsoil. This movement of clay has not occurred in the Hennepin and Lawson soils to any noticeable extent. Iron and organic matter are jDrimarily responsible for the colors of a soil. Organic matter gives the soils a dark color, and iron makes them reddish brown or yellow. If the iron is not uniformly distributed, and if the soil par- ticles are not coated with iron, the soil particles retain their natural color, which is gray. Formed where drainage is good is a ferric oxide, which is red. As a result, reddish or brownish soils, for example the Pana, Negley, Pike, and Hickoi'y, occur in areas where the iron is oxidized. Where drainage is somewhat poor or is only moderately good, the ferric iron is hydrated and the soils have a more yellowish color. The yirden, Cowden, and other poorly drained soils have a grayish color because the iron in tliose soils is poorly oxidized and is in the ferrous form. Ferrous oxide is only slightly soluble and tends to concentrate in some places where it can be oxidized as the result of a fluctuating water table. This oxidation produces the mottled pattern of gray and brown colors characteristic of poorly drained soils. In many poorly drained and somewhat drained soils, the iron is segregated in small, hard nodules or con- cretions, commonly called buckshot. Genesis of Selected Horizons Because of their extent in Montgomery County, and because of their effect on soil management, the soils that contain a f ragipan and those that contain natric horizons (horizons high in content of exchangeable sodium) are of special interest. Results of recent research, discussed in the following paragraphs, have helped to increase our under- standing of these horizons. Profiles of soils containing these horizons, as well as profiles of the other soils mapped in this county, are described in detail in the sec- tion "Descriptions of the Soils." Fragipan horizons A fragipan horizon consists of a layer that is dense or brittle when dry and appears to owe its hardness to ex- treme density or compactness rather than to the content of much clay or to cementation. This horizon is often considered to be massive but consists of rather large, poor- ly formed, massive blocks that are bounded by streaks or cracks filled with gray, silty material. A fragipan hori- zon is slowly permeable to water and restricts the growth of roots. Tliough it appears to be cemented when dry, it loses its hard, brittle consistency when it is moistened. When the fragipan is thoroughly wet, it slakes down to a nonsticky or only slightly sticky mass. Wliether the hardness and brittleness are caused by cementation by some chemical agent or merely by dehydration of small amounts of clay between closely packed silt grains is not known. Moderately well drained Hosmer and O'Fallon soils have a fragipan of varying degrees of development in the lower part of their profile, and to a lesser extent, the Stoy soils also contain a fragipan. In this county these horizons are less strongly develoj)ed than those m soils farther south in Illinois, but they definitely restrict the movement of water and the development of roots. Or PIASA ^^■^ q^*^^^ — ^---^ ^ ^""^^'^^ ~-^--x-2 ^ /> TAMALCO / y / W /^^'^ • / '' COWDEN • / / 1 id 1 I 1 1 1.0 2,0 PERCENT ORGANIC CARBON 5 25 45 40 PERCENT CLAY(<,002mm,) PIASA 80 4.0 8.0 EXCHANGEABLE SODIUM (me./IOOg.) Figure 15. — Some properties of selected soils that have a claypan in the subsoil. MONTGOMERY COUNTY, ILLINOIS 87 Recent studies of Illinois soils that contain a fragipan (8) give general characteristics, relationships in the field, mineralogy, and micromorphology of the Hosmer silt loams. The genesis of the fragipan in those soils is be- lieved to be related to their silty texture, to the stage of weathering, aiul to the depth to a tempoi'ary or perched water table. Natric horizons Among the most difficult soils to manage in Montgomery County are the soils that contain natric horizons, that is, soils that have a subsoil that is high in content of exchange- able sodium. These are often called slickspots. They occupy areas of irregular shape that range from only a few square feet to more than 100 acres in size. The soils that contain natric horizons are the Walshville loams, developed pri- marily in Illinoian glacial till, and the Tamalco, Huey, and Piasa silt loams, developed primarily in loess. Walshville soils occur in the valleys cut into the glacial till plain by streambed erosion. In these soils the lateral movement of water from the adjacent higher areas is thought to have caused sodium to concentrate in the sub- soil. In some places the Tamalco soils have develoj^ed under similar topographic conditions in slightly entrenched val- leys that have a cover of loess. In many places, however, the Tamalco soils are on convex ridges above the general till plain. In this type of topography, lateral seepage is less likely to have contributed to the content of sodium in these soils. The Huey and Piasa soils are at the base of slopes or near the edges of drainageways in some places. In most places, however, nearly level areas of those soils are inter- mingled with areas of acid Herrick, Cowden, and Cisne silt loams. The mechanism that causes the exchangeable sodium to concentrate is more complicated in nearly level areas and on ridgetops than in other places. The sequence of horizons in soils that contain natric horizons is similar to that of the soils with which they occur, but the surface layer is lighter colored, the subsur- face (A2) horizon is thinner, and the subsoil is shallower than in associated soils. Also, carbonate concretions are scattered throughout the B horizons (5). Soils that con- tain natric horizons liave higher pH values, that is, are alkaline, and contain mucli more exchangeable sodium than the soils with which they occur (see fig. 15). For example, the Huey, Piasa, Tamalco, and other soils that contain natric B horizons have pH values higher than 7.5 and con- Non-Natric INITIAL STAGE Incipient Natric tain 3 to 7 milliequivalents of exchangeable sodium (Na) per 100 grams of soil. In contrast, the Cisne, Cowden, and Herrick soils with which those soils occur generally have pH values of less than 6.5 and a content of exchangeable sodiiun of less than 1 milliequivalent per 100 grams of soil. In the B horizons of soils that contain natric horizons, the content of exchangeable sodium ranges from about 10 to 30 percent of the cation-exchange capacity. Below the B horizons of solonetzic soils, the content of exchangeable sodium decreases with increasing depth. The underlying Illinoian till and the Pennsylvanian bedrock contain little exchangeable sodium, which suggests that these two under- lying materials are not the primary source of sodium in loess-derived soils of Illinois that contain natric horizons Detailed chemical and mineralogical analyses of these loessal soils that contain natric horizons indicate that the exchangeable sodium in those soils originated chiefly from weathering in place of sodium-rich feldspars (which also contain potassium) of the parent loess (^7). Because the loess in which these soils formed appears to have the same characteristics as that in Avhich the associated soils formed, and these soils have been subjected to the same degree of weathering as the associated soils, it is suggested that differential redistribution of the soluble products of weathering is I'esponsible for the accumulations of ex- changeable sodium (Na) in soils that contain natric hori- zons, such as the Huey, Piasa, and Tamalco. Studies made by Frazee and others (G) show that though the soils that contain natric horizons are only one-seventeenth as perme- able as the soils with which they occur, the paleosols in the Illinoian till beneath the natric horizons are five times as permeable as those undei'lying the associated soils. Initially, the calcium, magnesium, sodium, and other solulile salts produced by weathering, originating both within and without the current areas of soils that contain natric horizons, would have concentrated in the lower part of the loess, which is underlain by more permeable till (27) (fig. 16, initial stage). Drying of these salt solutions late in summer, and decreasing pressures of carbon dioxide in the subsoil, has caused the solubility limits of the cal- cium and magnesium carbonates to be exceeded. As a re- sult, these carlx)nates were precipitated out and formed concretions, and the relative pi-o]joi-tions of sodium in solution increased by a corresponding amount. As the B horizons became dispersed by receiving continued accumu- ADVANCED STAGE Non-Natric | Natric Loess — ♦■ STREAMLINES X?;': MORE PERMEABLE TILL ZONE CARBONATE CONCRETIONS Figure 16. — Movement of moisture in soils that contain natric horizons. 88 SOIL SURVEY latioiis of exchangeable sodium, they became nearly imper- vious, and movement of moisture through those horizons became very slow. During wet seasons, these B horizons were not saturated, or they became satui'ated much more slowly than the B horizons of associated soils. The mois- tui'e gradient between soils that contain natric horizons and soils that lack such horizons favors the movement of salts into the subsoil of natric soils and the preservation of salts that previously had accumulated. Because of this mechanism, dispersion of the B horizons has progressed, both laterally and vertically, from the point of initial dispersion. Upward migration of dispersed material of the B hori- Z021S from the initial point of dispersion has resulted as a consequence of the very slow permeability, which averages only O.OIT inch per hour, according to studies made by Frazee and others (6'). The zones where dispersion is tak- ing place are seldom saturated with water, even during wet seasons, and hence are subjected to severe drying late in summer. Solutions of salts that move vertically through the soil are intercepted and subsequently are concentrated along the upper l)oundary of these zones. Through repeated cycles of this process, tlie horizon that is dispersed with sodium gradually migrates upward to within a few inches of the soil surface. This explains why the depth to the subsoil in soils that contain natric horizons is so shallow, even in nearly level or unei'oded areas. It also explains why plowing of these soils to a normal depth often pentrates the siibsoil and incorporates material from the subsoil into the plow layer. Development of a dispersed horizon results in an inver- sion of the drainage characteristics (permeability), in that a soil that originally was the most pei-meable becomes the least penneable after dispersion takes place (see fig. 16, advanced stage). Soils with which natric soils occur re- ceive a considerably greater volume of water than they nor- mally would receive through rainfall because they also receive water that moves laterally to them from the soils that contain nearly impermeable natric horizons. Tliis may provide a mechanism that limits the lateral expansion of soils that contain natric horizons. It functions if drainage of the associated soils is good enough to leach out of the profile excess sodium salts that oi'iginated from the perched water table of adjacent natric soils. The foregoing paragraphs explain why soils that con- tain natric horizons are closely intenningled with other soils. Soils that contain natric horizons are most extensive in the southeastern part of ^lontgomery County, where they occupy nearly 50 percent of some areas of upland prai- ries. To the noith and w^est, the acreage of these soils be- comes progressively smaller, and those soils occupy less than 1 percent of the total acreage in the northwestern part of the county. This pattern of occurrence of these soils is caused by the decrease in soil weathering and in accumulation of sodium, as the layer of loess becomes pro- gressively thicker from the southeastern part of the county to the noi-thwestern part. Classification of the Soils Soils are classified so that we can more easily remember their significant characteristics. Classification enables us to assemble knowledge al)out the soils, to see their relation- ship to one another and to the whole environment, and to develop principles that help us understand their behavior and their resi)onse to manipulation. First through classi- fication, and then through use of soil maps, we can apply our knowledge of soils to specific fields and other tracts of land. Thus, in classification, soils are placed in narrow cate- gories tliat are used in detailed soil surveys so that knowl- edge about the soils can be organized and used in managing farms, fields, and woodland ; in developing rural areas ; in engineering work; and in many other ways. Soils are placed in broad classes to facilitate study and comparison in large areas, such as countries and continents. Two systems of classifying soils have been used in the United States in recent vears. The older svstem was adopted in 1938 (2) and later revised (24). the system currently used was adopted for general use by the National Cooperative Survey in IDGo. The current system is under continual study. Therefore, readers interested in develop- ments of the current system should search the latest litera- ture available (23, 25). The soil series in Montgomery County are placed in some categories of the curi'ent system and in the great soil groups of the older system in table 9. In the current system, the criteria used as a basis for classification are soil properties that are cbservable and measurable. The properties are chosen so that the soils of similar genesis, or mode of origin, are grouped together. Six categories make up the current system. Beginning with the broadest, these are order, suborder, great group, sul)- group, family, and series. The classes of the current system are briefly defined in the following paragraphs. Order.' — Ten soil orders are recognized. They are Entisols, Vertisols, Inceptisols, Arfdisols, Mollisols, Spodosols, Alfisols, Ultisols, Oxisols, and Histosols. The properties used to differentiate these soil orders are those that tend to give broad climatic groupings of soils. The two exceptions to this are the Entisols and Histosols, which occur in many different kinds of climate. Tlie three orders in Montgomery County are Alfisols, Mollisols, and Inceptisols. Alfisols have a distinct accumulation of clay in the B horizon and have a base saturation of niore than 85 per- cent. The base saturation increases with increasing depth. Mollisols have formed under grass and have a thick, friable, dark-colored surface layer that is well supplied with bases. The name is derived from the Latin word mollis, meaning soft. Inceptisols generall;y form on yomig, but not recent, land surfaces. Their name "is derived from the Latin word in- ptum, meaning beginning. It indicates that the develop- ce ment of these soils is just beginning. Suborder. — Each order is subdivided into groups (suborders) that are based mostly on soil characteristics that seem to produce classes having the greatest similarity from the standpoint of their genesis. Suborders narrow the broad climatic range of soils that are in orders. Soil characteristics used to separate sulwrders mainly reflect either the presence or absence of waterlogging, or soil differences produced through the effects of climate or vegetation. The names of suborders contain two syllables, the last of which indicates the order. An example is Aquepts {Aqu, meaning water or wet, and ept., from Inceptisol). Great Group. — Soil suborders are separated into great groups on the basis of uniformity in kinds and sequences MONTGOMERY COUNTY, ILLINOIS Table 9. — Classification of soil series in Montgomery County, III. 89 Soil series Family Subgroup Order Great soil group of the 1938 system Blair Fine-loamy, mixed, mesic Fine-silty, mixed, mesic Aquic Ilapludalfs Typic Hapludalfs Argiaquic Argialbolls MoUic Albaqualfs Udollic Ochraqualfs Cumulic HajDlaquoUs Alfisols Alfisols Mollisols Alfisols Alfisols Mollisols Gray-Brown Podzolic soils. Camden Gray-Brown Podzolic soils. Planosols. Planosols. Chauncey Cisne Fine, montmorillonitic, mesic Fine, montmorillonitic, mesic Fine, montmorillonitic, mesic Fine-silty, mixed, noncalcareous, Clarksdale Colo Gray-Brown Podzolic soils inter- grading toward Brunizems. Alluvial soils. Cowden Douglas Fine, montmorillonitic, mesic Fine-silty, mixed, mesic Fine-silty, mixed, mesic Fine-silty, mixed, mesic Fine-silty, mixed, noncalcareous, mesic. Fine-loamy, mixed, mesic Fine-montmorillonitic, mesic Fine-loamy, mixed, mesic Fine-silty, mixed, mesic Fine, montmorillonitic, mesic Fine-silty, mixed, mesic Fine, montmorillonitic, mesic Coarse-loamy, mixed, mesic Fine-silty, mixed, mesic Fine-loamy, mixed, mesic Fine-loamy, mixed, mesic Fine, montmorillonitic, mesic Fine-silty, mixed, mesic Fine-loamy, mixed, mesic Fine, montmorillonitic, mesic Fine-silty, mixed, mesic Fine-silty, mixed, mesic Fine-silty, mixed, mesic Fine, montmorillonitic, non- calcareous, mesic. Fine-silty, mixed, mesic Fine-silty, mixed, mesic Fine-silty, mixed, mesic Fine, montmorillonitic, mesic Fine-loamy, mixed, mesic Fine-loamy, mixed, mesic Fine, montmorillonitic, non- Mollic Albaqualfs Typic ArgiudoUs Argiaquic Argialbolls Typic ArgiudoUs Typic Haplaquolls. Alfisols Mollisols Mollisols Mollisols Mollisols Planosols. Brunizems. Ebbert Humic Gley soils intergrading Harrison Harvel.. . . toward Planosols. Brunizems. Humic Gley soils. Regosols. Brunizems intergrading toward Planosols. Gray-Brown Podzolic soils. Gray-Brown Podzolic zoils. Planosols intergrading toward Brunizems. Solonetz soUs. Hennepin Herrick Hickory Hosmer Hoyleton Huey Typic Eutrochrepts Argiaquic Argialbolls Typic Hapludalfs Typic Fragiudalfs Aquollic Hapludalfs Typic Natraqualf s Aquic ArgiudoUs Fluventic Hapludolls Cumulic Hapludolls Ultic Hapludalfs Udollic Ochraqualfs Udollic Ochraqualfs Aquic ArgiudoUs Typic ArgiudoUs Mollic Natraqualfs Ultic Hapludalfs Typic Ochraqualfs Fluventic Hapludolls Cumulic Haplaquolls Mollic Hapludalfs Aerie Ochraqualfs Albaquic Fragiudalfs Typic Natrudalfs Cunuilic Hapludolls Typic ArgiudoUs Typic Argiaquolls Inceptisols Mollisols Alfisols Alfisols Alfisols Alfisols Mollisols Mollisols Mollisols Alfisols Alfisols Alfisols Mollisols Mollisols Alfisols Alfisols Alfisols Mollisols Mollisols Alfisols Alfisols Alfisols Alfisols Mollisols Mollisols MoUisols Ipava Brunizems. Landes Alluvial soils. Lawson Neglev Alluvial soils. Gray-Brown Podzolic soils. Brunizems. > Planosols intergrading toward Brunizems. Brunizems. Brunizems. Solonetz soils Nokomis Oconee O'Fallon Pana Piasa Pike Racoon Radford Shiloh Sicily Starks Stoy Tamalco TerriL_- Gray-Brown Podzolic soils. Planosols. Alluvial soils. Humic Gley soils. Gray-Brown Podzolic soils intei- grading toward Brunizems. Gray-Brown Podzolic soils. Gray-Brown Podzolic soils. Solonetz soils. Brimizems. Velma Virden2 Brunizems. Humic Gley soils. Walshville Weir calcareous, mesic. Fine, mixed, mesic Fine, montmorillonitic, mesic Typic Natrudalfs Typic Ochraqualfs Alfisols Alfisols Solonetz soils. Planosols. ' Brunizems intergrading toward Gray-Brown Podzolic soils. 2 Included with the Virden soils in Montgomery County are some Typic Haplaquolls, fine-silty, mixed, mesic, which resemble the Sable soils mapped in counties to the north. of major soil horizons and other features. The horizons used as a basis for distinguisliing between great groups are those in which (1) clay, iron, or htmitis has accumti- lated; (2) pans that interfere with growth of roots, move- ment of water, or both, have formed; or (3) a thick, dark- colored sitrface horizon has developed. The other features commonl}- used are the self-mulching properties of clay, temperatttre of the soil, major differences in chemical com- position (mainly the bases calcitnn, magnesium, sodium, and potassium), or the dark-red or dark-brown colors as- sociated with soils formed in material weathered from basic rocks. Names of the great groups consist of three or four syl- lables. They are made by adding a prefix to the name of the suborder. Ati example is Haplaquoll (Ilapl meaning mini- mum horizon, and aquol.l, meaning dark soils seasonally saturated with water) . The great group is not shoAvn separately in table 9, because it is the last word in the name of the subgroup. Subgroup. — Great soil groups are subdivided into sub- groups. One of tliese represents the central, or typic, seg- ment of tlie group. Other stibgroups have properties of the group but have one or more properties of another great group, suborder, or order, and these are called intergrades. Also, subgroups may be established for soils having prop- erties that intergrade outside the range of any other great group, suborder, or order. The names of subgroups are formed by placing one or more adjectives ahead of the name of the great group. An exam[)le is Cumidic Hap- laquolls. 90 SOIL SURVEY Family. — Families are separated within a subgroup, pi'imarily on the basis of properties that are important to the growth of phxnts or to the behavior of soils used for engineering. The main properties considered are texture, mineralogy, reaction, soil temperature, permeability, thick- ness of horizons, and consistence. The names of families consist of a series of adjectives that precede the name of a subgroup. The adjectives used are the class names for soil texture, mineralogy, and so on (see table 9). An example is the fine-silty, mixed, mesic family of Cumulic Hapla- quolls. All the soils in Montgomery County are in the mesic family. They have soil temperatures of 47 to 59 degTees Fahrenheit at a depth of 20 inches, and summer and winter temperatures that differ more than 9 degrees Fahrenheit. Laboratory Data for Selected Soil Profiles Physical and cliemical laboratory data considered rep- resentative for selected soil profiles in Montgomery County are given in table 10. These data are useful to soil scien- tists in classifying soils and in developing concepts of soil genesis. They are helpful for estimating fertility, tilth, and other properties that affect soil management, and they also serve as a check against field estimates and determina- tions. The soils sampled are those of the Douglas, Hari'i- son, Piasa, and Tamalco series. Profiles of the Piasa and Tamalco soils are described in the section "Descriptions of the Soils."' Profile descriptions of the Douglas and Har- rison soils follow : Table 10. — Laboratory data for selected soil profiles [Laboratory analysis were made by members of the Department of Agronomy, University of Illinois] Particle -size distribution Exchangeable cations ^ Horizon Depth Organic carbon ' (meq. per 100 gm. of soil) Cation- exchange Base satura- Soil type and location Sand Silt Clay pH (2.0- (0.05- «0.602 capacity tion 0.05 0.002 mm.) Ca Mg K Na mm.) mm.) In. Pet. Pet. Pet. Pet. Pd. Douglas silt loam: T. Ap 0-8 3.3 74. 5 22. 2 1. 69 10. 5 1.8 0.4 0. 1 1.5. 5 83 6.2 9 N., R. 4 W., sec. Al 8-12 1.8 71. 3 26.9 1. 33 8.5 2.8 .3 16. 9 69 5. 5 9, SW160, NW40, Bl 12-17 1.5 68. 1 30.4 .97 8.8 4.7 . 3 , 1 18. 9 74 5.3 SWIO. B21 17-24 1. 1 67. 4 31. 5 .79 8.8 5. 7 . 4 19.8 76 .5.3 B22 24-31 1.3 7L4 27.3 .64 7.5 5.2 . 3 17.2 77 5.2 B31 31-39 2. 1 72. 6 25. 3 .58 7.4 5.2 .3 16. 4 79 5. 2 IIB32 39-47 18.4 61. 4 20.2 .07 6. 1 4.3 . 2 12. 9 83 5. 2 IIIC 47-62 31.8 51. 1 17. 1 . 18 4.8 3.5 . 2 • 1 10.2 84 5.4 Harrison silt loam: Ap 0-8 2.9 77. 7 19. 4 1. 27 9. 1 2. 6 .3 14. 9 82 6.0 T. 10 N., R. 4 W., Bl 8-13 1. 6 70. 28. 4 . 91 9. 7 4. 4 . 4 18. 2 80 5.7 sec. 7, NE160, B21 13-18 1. 7 65.7 32.6 .73 10.8 6.8 . 4 22. 82 5. 6 SW40, NWIO. B22 18-26 1. 5 6.5. 8 32. 7 .61 10. 4 7.9 . 4 22. 5 84 5. 7 B31 26-3.5 1. 7 69. 9 28. 4 . 44 8.9 7. 4 .4 20. 84 5. 6 B32 35-46 4. 2 71. 9 23. 9 .33 7. 7 6. 6 .3 '. 2 17.2 86 5. 6 CI 46-52 9.5 70. 20.5 .22 6. 9 5.7 . 2 . 2 14. 9 87 .5.7 IIC2 .52-57 17.7 64. 2 18. 1 . 18 6.0 5.0 . 2 . 2 13. 2 86 5.7 IIIC3 57-62 27. 6 57. 5 14. 9 . 15 4.8 4. . 1 . 2 10. 7 84 5. 9 Piasa silt loam: ^ Ap 0-8 6. 7 82.3 11.0 1.09 7. 8 2. 6 . 1 .8 9. 1 123 6.6 T. 9 N., R. 4 W., A 2 8-12 6.7 72.9 20. 4 .51 7. 5 6.3 . 2 2. 14. 114 7. 4 sec. 26, NE160, B21t 12-16 6. 8 61.6 31.6 .47 9. 8 10. 8 . 4 3. 6 19. 131 7. 6 NE40, NEIO. B22t 16-20 2.9 5.5.9 41.2 .45 IL 6 14. 6 . 5 6.0 26. 6 121 7. 7 B23t 20-26 2.6 57. 4 40.0 .37 12.4 14. 5 .5 6.9 27.0 124 s. B24t 26-33 3.3 62. 1 34.6 .27 10. 5 12. 6 .4 6.4 23. 5 121 7. 9 B3 33-37 2.8 68. 1 29. 1 . 22 9. 5 10.4 . 4 .5.4 19. 5 128 7. 8 CI 37-48 2.9 72. 2.5. 1 . 14 8. 2 8.6 .3 3. 3 16. 8 119 7. 7 IIC2 48-55 14. 4 63. 2 22.4 . 13 8.2 7.4 . 2 2.0 15. 2 113 7. 4 Tamalco silt loam: ^ Ap 0-6 6.7 76.7 16. 6 1. 86 4. 8 2.7 . 1 .2 13.6 56 4.9 T. 9 N., R. 4 W., A 2 6-9 .5.6 73. 21.4 1. 09 3. 1 2. 4 . 1 . 4 14. 4 43 4. 9 sec. 26, NE160, B&A 9-11 3. 6 68.6 27. 8 . 94 4. 2 3. 8 . 2 1. 1 17. 1 55 5. NW40, NWIO. B21t 11-17 2.4 5,5.0 42. '6 1.09 7. 8 8.7 '. 4 2.8 27.9 70 5.4 B22t 17-28 2. 8 63. 9 33.3 .39 10. 1 11.2 . 6 4.7 25. 5 98 7. 4 B3t 28-35 3.5 72.9 23.6 .20 8. 1 8.2 .3 4. 6 18.0 111 7. 9 C 35-42 8. 8 71. 6 19. 6 . 19 6.9 6.6 . 2 3. 4 14.4 119 8. 2 IIAlb 42-54 23. 2 59. 9 16.9 . 15 5. 4 4.9 . 2 2. 1 11. 8 105 8. IIBb 54-60 30. 52. 1 17.9 . 13 5.6 5.2 . 2 1. 5 11.8 105 7. 9 1 The percentage of organic carbon times 1.724 equals the per- centage of organic matter. 2 One milliequivalent of calcium (Ca) per 100 grams of soil material equals 400 pounds per acre, or per 2 million pounds of soil material, 1 milliequivalent of magnesium (Mg) per 100 grams of soil material equals 240 pounds per acre, or per 2 million poimds of soil material; 1 milliequivalent of potassium (K) per 100 grams of soil material equals 780 pounds per acre, or per 2 million pounds of soil material. 3 A detailed description of the, soil profile at this site appears in the section "Descriptions of the Soils." MONTGOMERY COUNTY, ILLINOIS 91 Profile of Douglas silt loam (40 feet north and 18 feet east of comer post adjacent to walnut tree in about the SW. corner of the NW40 SW160, sec. 9, T. 9 N., R. 4 W. ; laboratory numbers 19825 to 19832, inclusive) : Ap — to 8 inches, very dark grayish-brown (lOYR 3/2) silt loam ; moderate, fine, granular structure ; friable ; abrupt, smooth boundary. Al-8 to 12 inches, very dark grayish-brov^'n (lOYR 3/2) and dai-k-brown (lOYB 4/3) silt loam; strong, fine to coarse, granular structure ; friable ; clear, smooth boundary. Bl— 12 to 17 inches, dark-brown (lOYR 4/3) and dark yel- lowish-brown (lOYR 4/4) heayy silt loam that is dark yellowish brown (lOYR 4/4) if crushed; strong, coarse, granular to fine, subangular blocky structure; dark-browu (lOYR 3/3) coatings on the peds ; slightly firm ; clear, smooth boundary. B21 — 17 to 24 inches, dark yellowish-brown (lOYR 4/4) and yellowish-brown (lOYR 5/4) light silty clay loam; strong, tine to medium, subangular blocky structure ; nearly continuous, dark-brown (lOYR 3/3) coatings on the peds ; firm ; gradual, smooth boundary. B22— 24 to 31 inches, dark yellowish-brown (lOYR 4/4) and yellowish-brown (lOYR 5/4) light .silty clay loam; moderate, medium, sul)angular blocky structure; patchy, dark-brown (lOYR 3/3) coatings on the peds; slightly firm ; gradual, smooth boundary, B31 — 31 to 39 inches, brown (7.5YR 4/4) to yellowish-brown (lOYR 5/4) heavy silt loam; few, fine, di.stiuct, light brownish-gray (lOYR 6/2) mottles; weak, medium to coarse, subangular blocky structure ; few, thin, patchy, dark-brown (7,5YR 3/2) coatings on the peds; fria- ble ; clear, smooth boundary. IIB32^— 39 to 47 inches, brown (7,5YR 4/4) gritty silt loam; very weak, coarse, subangular blocky structure ; some fine, black specks; slightly firm; gradual, smooth boundary. (Considered to be Farmdale loess. ) IIIC — 47 to 62 inches, brown (7.5YR 4/4) gritty silt loam; very weak, coarse, angular to subangular blocky struc- ture; slightly firm. (Con.sidered to be Illinoian glacial drift.) Profile of Harrison silt loam (240 feet east and 123 feet south of the NW. corner of the SW40 of NE160, sec. 7, T. 10 N., R. 4 W. ; laboratory numbers 19806 to 19814, inclusive) : Ap — to 8 inches, very dark grayish-brown (lOYR 3/2) silt loam ; weak, fine to medium, granular structure ; fri- able ; abri;pt, smooth boundary. Bl— 8 to 13 inches, dark-brown (lOYR 3/3) to brown (lOYR 4/3) silt loam; brown (lOYR 4/3) if crushed and has very dark grayish-brown (lOYR 3/2) coatings on the peds ; moderate, coar.se, granular to moderate, fine, .subangular blocky structure; friable; clear, smooth boundary. B21— 13 to 18 inches, brown (lOYR 4/3) silty clay loam ; brown (lOYR 4/3) if crushed and has dark-brown (lOYR 3/3) to vei-y dark grayish-brown (10YR3/2) coatings on the peds ; weak, medium, subangular blocky struc- ture breaking to moderate, coarse, granular struc- ture ; slightly firm ; clear, smooth boundary. B22— 18 to 26 inches, dark-browu (lOYR 4/3) to dark yellow- i;>h-brown ( lOYR 4/4 ) silty clay loam ; few, fine, prominent, strong-brown (7.5YR 5/6) mottles and a few, fine, faint, light brownish-gray (lOYR 6/2) mot- tles; dark grayish-brown (lOYR 4/2) clay coatings on the peds ; moderate, medium, subangular blocky struc- ture ; slightly firm: some black (lOYR 2/1) irou and manganese concretions ; gradual, smooth boundary. B31— 26 to 35 inches, dark yellowish-brown (lOYR 4/4) to yellowish-brown (lOYR 5/4) heavy silt loam; com- mon, fine, distinct, dark-brown (7.5YR 4/4) and strong-brown (7,5YR 5/6) mottles; dark grayish- brown (lOYR 4/2) coatings on the peds; weak, me- dium to coarse, subangular blocky structure ; slightly 1 In this profile the layer of Peorian loess, above the Farmdale loess, is somewhat thinner than normal. firm ; some iron concretions ; gradual, smooth boundary. B32— 35 to 46 inches, dark yellowish-brown (lOYR 4/4) to yellowish-brown (lOYR 5/4) silt loam; common, fine, distinct, dark-brown (7.5YR 4/4) to strong-brown (7.5YR 5/6) mottles and common, fine, faint, light brownish-gray (lOYR 6/2) mottles; dark grayish- brown (lOYR 4/2) coatings on the peds ; weak, coarse, subangular blocky structure ; friable ; few black (7.5YR 2/1) concretions; gradual, smooth boundary. CI — 46 to 52 inches, mixed light brownish-gray (lOYR 6/2) and dark yellowish-brown (lOYR 5/6) silt loam ; some grit; dark-brown (7.5YR 4/2) coatings on the peds; very weak, coarse, subangular blocky stri;cture ; fri- able; few black (10YR2/1) concretions; clear, smooth boundary. IIC2— 52 to 57 inches, dark-brown (7.5YR 4/2 to 4/4) silt loam ; some grit; few, fine, faint, strong-brown (7.5YR 5/6) mottles and a few, fine, distinct, light brownish- gray (lOYR 6/2) mottles; weak, coar.se, angular blocky structure ; friable ; a few dark concretions ; gradual, smooth boundary. (Farmdale loess.) IIIC3— 57 to 62 inches, dark yellowish-brown (7.5YR 4/4) gritty silt loam ; common, medium, distinct, dark- brown (7.5YR 3/2) mottles and a few, medium, faint, strong-brown (7.5YR 5/6) mottles; dark grayish- brown (10YR4/2) to gra.vii3h-brown (lOYR 5/2) clay films ; weak, thick, platy structure ; firm. Field and Laboratory Methods The samples used to determine the data in table 10 were collected from carefully selected pits. All laboratory analyses were made on ovendry material that had passed a 2-millimeter sieve. The soils were analyzed by the Depart- ment of Agronomy of the University of Illinois. Standard methods were used. Determinations of the amount of clay were made by the pipette method {IJi,, 15^ 10) . Reaction of the saturated paste was measured with a glass electrode. Organic carbon was determined by wet combustion, using a modification of the Walkley-Black method {20). The cation-exchange capac- ity was determined by direct distillation of absorbed am- monia {20). To determine extractable calcium and mag- nesimn, calcium was separated as calcium oxalate, and magnesium as magnesium ammonium phosphate {20). Extractable potassium was determined on the original ex- tracts with a flame spectrophotometer. Literature Cited (1) American Association of State Highavay Officials. 1961. standard specifications for iiighm'ay materials AND methods of SAMPLING AND TESTING. Ed. 8, 2 V., illus. (2) Baldwin, Mark, Kellogg, Charles E., and Thoep, James. 1938. SOIL CLASSIFICATION. U.S. Dept. Agi'. Ybk. 1938 : 979-1001. (3) Baeger, G. L., Shaw, R. H., and Dale, R. F. 1959. chances of receiving selected amounts of PRE- CIPITATION IN the north CENTRAL REGION OF THE UNITED STATES. Agr. Expt. Sta., Iowa state Univ., 277 pp. (4) Broadfoot, W. M. 1960. field guide for evaluating Cottonwood sites. USD A South For. Expt. Sta. Occas. Paper 178, 6 pp., illus. (5) Fehrenbacher, J, B., Wilding, L. P,, Odell, R, T., and Melsted, S, W. 1963. characteristics of SOLONETZIC soils in ILLINOIS. Soil Sci. Soc. Amer. Proc. 27 : 421-431. (6) FiuzEE, C, .J., Odell, R, T,, and Fehrenbacher, G. B. 1968. moisture regimes in solonetzic and associated soils IN south-central ILLINOIS. Soil Sci. 105 : 362-368. 92 SOIL SURVEY (7) (S) (9) (10) (11) (12) (13) (14) (15) (16) (17) (IS) (19) (20) (21) (22) (23) (24) (25) (26) (27) (28) Frte, J. C, Glass, H. D., and Willman, H. E. 1962. STKATIGRAPHY AND MINERALOGY OF THE WISCONSINAN LOESSES OF ILLINOIS. 111. State Geol. Survey Cir. 334, 55 pp., illus. Grossman, R. B., Fehbenbacher, J. B., and Beiavers, A. H. 1959. fragipan soils of Illinois : I, II, III. Soil Sci. Soc. Amer. Proc. 28 : 65-75. HORBERG, LeLAND. 1950. BEDROCK TOPOGRAPHY OF ILLINOIS. 111. State Geol. Survey. Bui. 73, 111 pp., illus. Huff, F. A. and Changnon, S. A. 1959. HAIL cLi^rATOLOGY OF ILLINOIS. 111. State Water Survey. Rpt. of Invest. No. 38, 46 pp. Illinois Technical Forestry Association. 1952. forest PLANTING PRACTICES FOR ILLINOIS. ReV. 1957. 35 pp., illus. Glossary 1956. recommended forest practices for Illinois hard- VFOOD timber types. Rev. 1957. 16 pp. Joos, L. A. 1960. freeze probabilities in Illinois. 111. Agr. Expt. Sta. in cooperation with U.S. Weather Bur. Bui. 650, 16 pp., illus. Kilmer, V. J. and Alexander, L. T. 1949. methods of making mechanical analyses of soils. Soil Sci. 68 : 1.5-24. and MuLLiNS, J. F. 1954. improved stirring and pipetting apparatus for T.IE- chanical analy'sis of soils. Soil Sci. 77 : 437-441. KosANKE, R. M., Simon, J. A., Wanless, H. R., and Willman, H. B. 1960. classification of the Pennsylvania strata of Illi- nois. 111. State Geol. Survey, Rpt. of Invest. 214, 84 pp., illus. Leighton, M. M. and Brophy, J. A. 1961. iLLiNoiAN GLACiATioN IN ILLINOIS. Jour. Geol. 69 : 1-31, illus. , Ekblaw, G. B., and Horbebg, L. 1948. physiographic divisions of Illinois. 111. State Geol. Survey, Dept. of Invest. No. 129, 33 pp., illus. Olmstead, L. B., Alexander, L. T., and Middleton, H. E. 1930. A pipette method of mechanical analysis of soils BASED ON improved DISPERSION PBOCEDURE. U.S. Dept. Agr. Tech. Bui. 170, 22 pp., illus. Peech, Michael, Alexander, L. T., Dean, L. A., and Reed, J. Fielding. 1947. METHODS OF SOIL ANALYSIS FOB SOIL-FERTILITY INVES- TIGATIONS. U.S. Dept. Agr. Cir. 757, 25 pp. Portland Cement Association. 1962. PCA soil PRIMER. 52 pp., illus. Chicago, (Rev.) SCHNUB, G. L. 1937. YIELD, STAND, AND VOLUME TABLES FOR EVEN-AGED UP- LAND OAK FORESTS. USDA Tech. Bui. 560, 88 pp., illus. SiMONSON, Roy W, 1962. SOIL CLASSIFICATION IN THE UNITED STATES. Sci. 137 : 1027-1034. Thorp, James and Smith, Guy D. 1949. higher categories of soil classification : order, SUBORDER, AND GREAT SOIL GROUPS. Soil Sci. 67 : 117-126. United States Department of Agriculture. 1960. soil classification, a comprehensive SYSTEM. 7th Approximation. Soil Survey Staff, Soil Conserva- tion Service, 265 pp., illus. (Supplement issued in March 1967) Waterways Experiment Station, Corps of Engineers. 1960. the unified soil classification system. Tech. Memo. .3-357, 2 v. Wilding, L. P., Odell, R. T., Fehrenbacheb, J. B., and Beavers, A. H. 1963. SOURCE AND DISTRIBUTION OF SODIUM IN SOLONETZIC . SOILS IN nxiNois. Soil Sci. Soc. Amer. Proc. 27 : 432-438, illus. WiLLMAN, H. B., Glass, H. D., and Frye, J. C. 1963. MINERALOGY' OF GLACIAL TILLS AND THEIR WEATHERING PROFILES IN ILLINOIS. 111. State. Geol. Survey, Cir. 347, 55 pp., illus. Acidity. See Reaction, soil. Aeration, soil. The process by which air and other gases in the soil are renewed. The rate of soil aeration depends largely on the size and number of pores in the soil and on the amount of water that clogs the pores. Aggregate, soil. A single mass or cluster consisting of many primary soil particles held together, such as a clod, crumb, block, or prism. Alluvium. Soil material that has been transported and deposited by water. Available moisture capacity. The capacity of a .soil to hold water in a form available to plants. The amount of moisture held in a soil between field capacity, or about one-third atmosphere of tension, and the wilting coefficient, or about 15 atmospheres of tension. Terms for available moisture capacity given in this survey (determined to a depth of 60 inches) are the fol- lowing: Very high — 12 inches or more; high — 9 to 12 inches; moderate — 6 to 9 inches ; loiv — 3 to 6 inches ; and very loiv — - less than 3 inches. Base saturation. The degree to which soil material that has base- exchange properties is saturated with exchangeable cations other than hydrogen, expressed as a percentage of the cation- exchange capacity. Calcareous soil. A soil containing enough calcium carbonate (often with magnesium carbonate) to effervesce (fizz) visibly when treated with cold, dilute hydrochloric acid. Cation-exchange capacity. A measure of the total amount of ex- changeable cations that can be held by a soil. It is expressed in terms of milliequivalents per 100 grams of soil material that is neutral in reaction (pH 7.0) or at some other stated pH value. (Formerly called base-exchange capacity.) Clay. As a soil separate, the mineral soil particles less than 0.002 millimeter in diameter. As a soil textural class, soil material that is 40 percent or more clay, less than 45 percent sand, and less than 40 percent silt. Claypan. A compact, slowly permeable soil horizon that contains more clay than the horizon above and below it. A claypan is commonly hard when dry and plastic or stiff when wet. Colluvium. Soil material, rock fragments, or both, moved by creep, slide, or local wash and deposited at the base of steep slopes. Consistence, soil. The feel of the soil and the ease with which a lump can be crushed by the fingers. Terms commonly used to describe con.sistence are — Loose. — Noncoherent ; will not hold together in a mass. FriaMe. — When moist, crushes easily under gentle pressure be- tween thumb and forefinger and can be pressed together into a lump. Firm,. — When moist, crushes under moderate pressure between thumb and forefinger, but resistance is distinctly noticeable. Plastic. — When wet, readily deformed by moderate pressure but can be pressed into a lump ; will form a "wire" when rolled between thumb and forefinger. Sticky. — When wet, adheres to other material, and tends to stretch somewhat and pull apart, rather than to pull free from other material. Hard. — When dry. moderately resistant to pressure ; can be broken with difficulty between thumb and forefinger. Soft. — When dry. breaks into powder or individual grains un- der very slight pressure. Cemented. — Hard and brittle ; little affected by moistening. Cover crop. A close-growing crop grown primarily to improve and protect the soil between periods of regular crop production ; a crop grown between trees and vines in orchards and vineyards. Crop residue. That part of a plant, or crop, left in the field after harvest. Depth of soil. Thickness of soil over a specified layer, generally a layer that does not permit the growth of roots. Cla.sses used in this soil survey to indicate depth are the following: Deep — 36 inches or more ; moderately deep — 20 to 36 inches : shalloiv — 10 to 20 inches: and very shalloiv — less than 10 inches. Diversion (ditch). A broad-bottomed ditch, used to divert runoff so that it will flow around the slope to a safe outlet. ( See Ter- race.) A ridge of earth, generally a terrace, that is built to divert runoff from its natural course, and thus to protect areas downslope from the effects of such runoff. Drainage, natural. Refers to the conditions that existed during the time the soil was developing, as oppo.sed to altered drain- MONTGOMERY COUNTY, ILLINOIS 93 age, which is commonly the result of artificial drainage or ir- rigation but can be caused by the sudden deepening of a chan- nel or tlie blocking of a drainage outlet. The following classes of natural drainage are recognized : Excessively drained soils are commonly very porous and rapidly permeable, and they have low water-holding capacity. Someu-hat excessively drained soils are also vei->' i^ermeable and are free from mottling throughout their profile. Well-drained soils are nearly free from mottling and are com- monly of intermediate texture. Moderately irell drained soils commonly have a slowly i)erme- able hiyer in or immediately beneath the solum. They have uniform color in the A and upper B horizons and have mot- tling in the lower B and C horizons. Sontctcliat poorly drained soils are wet for .significant periods but not all the time, and in podzolic soils they commonly have mottles below a depth of G to 16 inches in the lower A horizon and in the B and C horizons. Poorly drained soils are wet for long periods, are light gray, and generally are mottled from the surface downward, though mottling may be absent, or nearly so, in some .soils. Very poorly drained soils are wet nearly all the time. They have a dark-gray or black surface layer and are gray or light gray, with or without mottling, in the deeper parts of the profile. Fragipan. A dense and brittle pan, or layer, that owes its hardness mainly to extreme density or compactness rather than to con- tent of much clay or cementation. Fragments that are removed are friable, but the material in place is so dense that roots cannot penetrate it and water moves through it very slowly by following vertical channels and cleavage planes. Genesis, soil. The manner in which a soil originated, with special reference to the processes responsible for the development of the solum, or true soil, from the unconsolidated parent material. Glacial drift. Rock material transported by glacial ice and then deposited ; also includes the assorted and unassorted materials ' deposited by streams flowing from glaciers. Glacial till. Unstratifled glacial drift that consists of clay, silt, sand, gravel, and boulders transported and deposited by gla- cial ice. Grassed waterway. A waterway planted to grass to protect against erosion ; some are graded or shaped to conduct runoff. Horizon, soil. A layer of soil, approximately parallel to the surface, that has distinct characteristics produced by soil-foi-ming proc- esses. These are the major horizons : horizon. — The layer of organic matter on the .surface of a min- eral soil. This layer consists of decaying plant residue. A horizon. — The mineral horizon at the surface or just below an O horizon. This horizon is the one in which living organi.sms are most active, and it is therefore marked by an accumu- lation of humus. The horizon may have lo.st one or more of soluble salts, clay, and sesquioxides (iron and aluminum oxides). B horizon. — The mineral horizon below an A horizon. The B horizon is in part a layer of change from the overlying A to the underlying C horizon. Tlie B horizon al.so has (1) dis- tinctive characteristics caused (1) by accumulation of clay, sesquioxides, humus, or some combination of these; (2) by prismatic or blocky struc-ture ; (3) by redder or stronger colors than the A horizon: or (4) by some combination of these. Combined A and B horizons are usually called the solum, or true soil. If a soil lacks a B horizon, the A horizon alone is the solum. G horizon. — The weathered rock material immediately beneath the solum. In most soils this material is presumed to be like that from which the overlying horizons were formi^d. If the material is known to be different from that in the solum, a Roman numeral precedes the letter C. R layer. — Con.solidated rock beneath the soil. The rock usually underlies a C horizon but can be immediately beneath the A or B horizon. Humus. The well-decomposed, more or less stable part of the organic matter in mineral soils. Infiltration rate. The rate at which water penetrates the surface of the soil at any given instant, usually expressed in inches per hour. May be limited by either the infiltration capacity of the soil or by the rate at which water is applied to the soil surface. Lacustrine deposit. Material deposited in lake water and expo.sed by the lowering of the water level or elevation of the land. Leached soil. A soil from which mo.st of the soluljle material has been removed from the entire profile or has been removed from one part of the i)rofile and has accumulated in another part. Lime concretion. An aggregate cemented by precipitation of calcium carbonate. Litter, forest. A surface layer of loose, organic debris in forests. It consists of freshly fallen or slightly decomposed organic materials. Loam. ( 1 ) Soil containing a relatively even mixture of sand and silt and a somewhat smaller proportion of clay, generally a desirable quality. May be subdivided into textxiral classes, such as sandy loam, loam, silt loam, and clay loam. (2) Spe- cifically, soil material containing 7 to 27 percent clay, 28 to 50 percent silt, and less than 52 percent sand. Loess. A fine-grained windblown deposit consisting dominantly of silt-.sized particles. Massive. Large, uniform masses of cohesive soil, in some places with ill-defined and irregular breakage, as in some of the fine- textured alluvial soils ; structureless. Medium-textured soil. Soil of very fine sandy loam, loam, silt loam, or silt texture. Morphology, soil. The makeup of the soil, including the texture, structure, consistence, color, and other physical, mineralogical, and biological properties of the various horizons that make up the soil profile. Mottled. Irregularly mai-ked with spots of different colors that vary in number and size. Mottling in .soils usually indicates poor aeration and poor drainage. Descriptive terms are as follows: Abundance — fcto, common, and many; size — fine, medium, and coarse ; and contrast — faint, distinct, and promi- nent. The size measurements are fine, less than 5 millimeters (about 0.2 inch) in diameter along the greatest dimension; medium, ranging from 5 millimeters to 15 millimeters (about 0.2 to O.G inch ) in diameter along the greatest dimension ; and coarse, more than 15 millimeters (about 0.6 inch) in diameter along the greatest dimension. Munsell notation. A system for designating color by degrees of the three simple variables — hue, value, and chroma. For example, a notation of lOYR 6/4 is a color with a hue of lOYR, a value of 6, and a chroma of 4. Organic matter. A general term for plant and animal matter, in or on tlie soil, in all stages of decomposition. Readily decom- posed organic matter is often distinguished from the more stable forms that are past the stage of rapid decomposition. Following are terms used in this soil survey to describe the content of organic matter; Very loiv — below 1 percent, by weight; loiv — 1 to 2 percent; moderate — 2 to 4 percent; and high — more than 4 percent. Outwash, glacial. The material swept out, sorted, and deposited beyond the glacial ice front by streams of melt water. In this county it consists of .sediment, in many places sandy and gravelly, deposited in layers on terraces. Pan. A layer in a soil that is firmly compacted or very rich in clay. Frequently the word "pan" is combined with other words that more explicitly indicate the nature of the layers ; for example, hardpan, frayipan. and eluypan. Parent material, soil. The disintegrated and partly weathered rock from which soil has formed. Ped. An individual natural soil aggregate, such as a crumb, prism, or block, in contrast to a clod, which is a mass of soil brought about by digging or other disturbance. Percolation. The downward movement of water through the soil, e.specially the downward flow of water in saturated or nearly saturated soil. Permeability, soil. The quality of a .soil that enables it to transmit air and water. The following relative classes of soil perme- ability, used in this soil survey, refer to estimated rates of movement of water in inches per hour through saturated, un- disturbed cores under a one-half inch head of water : Inches per hour Inches per hour Very slow___Less than 0.06 Moderate 0.63-2.00 Slow 0.06-0.20 Moderately rapid 2.00-6.3 Moderately slow— _0.20-0.63 Rapid 6.3-20.0 Poorly graded. A soil matei'ial consisting mainly of particles of nearly the same size. Because there is little diflierence in size of the particles in poorly graded soil material, density can be increased only slightly by compaction. 94 SOIL SURVEY Porosity, soil. The percentage of the soil (or rock) volume that is not occupied by solid particles, including all pore spaces filled with air and water. Reaction, soil. The degree of acidity or alkalinity of a soil, expressed in pH values. A soil that tests to pH 7.0 is precisely neutral in reaction because it is neither acid nor alkaline. An acid, or "sour," soil is one that gives an acid reaction ; an alkaline soil is one that is alkaline in reaction. In words, the degrees of acidity or alkalinity are expressed thus : pH pH Extremely acid Below 4.5 Miklly alkaline 7.4 to 7.S Very strongly acid 4.5 to 5.0 Moderately a 1 k a- Strongly acid 5.1 to 5.5 line 7.9 to 8.4 Medium acid 5.6 to G.O Strongly alkaline__ 8.5 to 9.0 Slightly acid G.l to 0.5 Very strongly alkaline Neutral 6.6 to 7.3 9.1 and higher Relief. The elevations or inequalities of a land surface, considered collectively. Sand. As a soil separate, individual rock or minei-al fragments in soils having diameters ranging from 0.05 to 2.0 millimeters in diameter. Most sand grains consist of quartz, but sand may be of any mineral composition. As a textural class, soil mate- rial that is 85 percent or more sand and not more than 10 percent clay. Silt. As a soil separate, individual mineral particles in a soil that range from the upper limit of clay (0.002 millimeter) in diam- eter to the lower limit of very fine sand (0.05 millimeter). As a textural class, soil material that is 80 percent or more silt and less than 12 percent clay. Slope classes. Soil slope is normally measured by using a hand level and is expressed in terms of percentage — the difference in elevation in feet for each 100 feet horizontal. In this soil survey, the slope classes are not indicated in the map symbol for soils that are nearly level. In soils that are sloping, how- ever, a capital letter following the soil type number shows the class of slope, for example, 134U. The slope classes gen- erally have the following range in gradient : A, less than 2 percent ; B, 2 to 4 percent; C, 4 to 7 percent; D, 7 to 12 per- cent : E, 12 to 18 percent ; F, 18 to 30 percent ; and G, more than 30 percent. Soil. A natural, three-dimensional body on the eartli's surface that supports plants and that has properties resulting from the integrated eifects of climate and living matter acting upon parent material, as conditioned by relief over a period of time. Solum. The upper part of a soil profile, above the parent material, in which the processes of soil formation are active. The solum in a mature soil includes the A and B horizons. Generally, the characteristics of the material in these horizons are unlike those of the underlying material. The living roots and other plant and animal life characteristic of the soil are largely confined to the solum. Stratified. Composed of or arranged in strata, or layers, such as stratified alluvium. The term is confined to geologic material. Layers in soils that result from the processes of soil forma- tion are called horizons ; those inherited from the parent mate- rial are called strata. Stripcropping. Growing alternate strips of close-growing crops and clean-tilled crops or fallow on the contour. Structure, soil. The arrangement of primary soil particles into compound particles or clusters that are separated from ad- joining aggregates and have properties unlike those of an equal mass of unaggregated primary soil particles. The principal forms of .soil structure are jjlaty (laminated), prismatic (ver- tical axis of aggregates longer than horizontal), columnar (prisms with rounded tops), hlocly (angular or subangular), and granular. Structureless soils are (1) single grain (each grain by itself, as in dune sand) or (2) massive (the particles adhering together without any regular cleavage, as in many claypans and hardpans) . Subsoil. Toilinically. the B horizon ; roughly, the part of the profile below plow depth. Substratum. Any layer lymg beneath the solum, or true soil; the C horizon. Subsurface layer. Technically, the A2 horizon, which lies between the surface layer and the subsoil. This horizon has about the same texture as the Al horizon, but it has a lighter color and is more strongly leached. Surface layer. A term used in nontechnical soil descriptions for one or more layers above the subsoil. Generally coincides with the A horizon. Terrace. An embankment, or ridge, constructed across .sloping soils on the contour or at a slight angle to the contour. The terrace intercepts surplus runoff so that it ma.v soak into the soil or flow slowly to a prepared outlet without harm. Terraces in fields are generally built so that they can be farmed. Terraces in- tended mainly for drainage have a deep channel that is main- tained in permanent sod. Texture, soil. The relative proportions of sand, silt, and clay par- ticles in a soil. The basic textural classes, in order of increas- ing proportions of fine particles, are sand, loamy sand, sandy loam, loam, silt loam, silt, sandy clay loam, clay loam, silty clay loam, sandy clay, silty clay, and clay. The sand, loamy sand, and sandy loam classes may be further divided by specify- ing "coarse," "fine," or "very fine." Tilth, soil. The condition of the soil in relation to the growth of plants, especially good soil structure. Good tilth refers to the friable state and is associated with high noncapillary porosity and stable, granular structure. A soil in poor tilth is nonfriable, hard, nonaggregated, and difficult to till. Topsoil. A presumed fertile soil or soil material, ordinarily rich in organic matter, used to topdress roadbanks, lawns, and gardens. 8E2 8e3 8f 8g ^3 46 i+8 50 7h 109 112 11 3A 113B 113B2 113c 113c 2 iiUb I27A I27B 127B2 127c 127C2 12 8b 128c 128C2 128D 132 13i+B 13^+02 138 13&^- l6iiA 16I+B 165 21I+B 2li+C For a full descriptlgs. Other information' Acreage and extet, tables 6, 7, and Estimated yields Map symbol 2 3A 3B 3B2 5C2 5C3 8d 8d2 8d3 Mapping unit Cisne silt loam^ Hoyleton silt loam, to 2 percent slopes roded-- Hoyleton silt loam, 2 to 5 percent slopes d.- Hoyleton silt loam, 2 to 5 percent slopes, erod eroded- Blair silt loam, 5 to 9 percent slopes, eroded- Blair soils, 5 to 9 percent slopes, severely er Hickory loam, 7 to 12 percent slopes Hickory loam, 7 to 12 percent slopes, eroded Hickory soils, 7 to 12 percent slopes, severely Hickory loam, 12 to 18 percent slopes Hickory loam, 12 to I8 percent slopes, eroded-- Hickory soils, 12 to 25 percent slopes, severel; eroded Hickory loam, 18 to 30 percent slopes Hickory loam, 30 to 60 percent slopes 1- Ipava silt loam *- Herrick silt loam f- Ebbert silt loam 1- Virden silty clay loam + - Radford silt loam 1- Racoon silt loam W Cowden silt loam id Oconee silt loam, to 2 percent slopes *- Oconee silt loam, 2 to U percent slopes f- Oconee silt loam, 2 to 4 percent slopes, erodedj- Oconee silt loam, 4 to 7 percent slopes |- Oconee silt loam, 4 to 7 percent slopes, erodedf- 'Fallon silt loam, 2 to 4 Harrison silt loam, to 2 Harrison silt loam, 2 to 4 Harrison silt loam, 2 to 4 Harrison silt loam, 4 to 7 Harrison silt loam, U to 7 percent slopes percent slopes percent slopes percent slopes, erod| percent slopes -r percent slopes, erodj"oded-- Douglas silt loam, 2 to 4 percent slopes ■!■- Douglas silt loam, 4 to 7 percent slopes -I--' Douglas silt loam, 4 to 7 percent slopes, erodec] eroded- Douglas silt loam, 7 to 12 percent slopes ^ eroded- Starks silt loam Camden silt loam, 2 to 4 percent slopes ■«, Camden silt loam, 4 to 7 percent slopes, eroded-j-- Shiloh silty clay loam-- Shiloh silt loam, overwash * — Stoy silt loam, to 2 percent slopes -5 Stoy silt loam, 2 to 4 percent slopes -s — Weir silt loam -pes- Hosmer silt loam, 2 to 4 percent slopes- Hosmer silt loam, 4 to 7 percent slopes- Described on page - 26 26 26 27 43 43 kk hk kk 21 3k 3k 16 39 39 13 29 16 30 1+1 k2 k2 36 36 36 36 36 31 k3 Ik 28 17 18 32 32 32 33 22 kk ■-5S. , PP- Management group kk IIIe-1 2k VIe-1 25 VIIe-1 25 VIe-1 19 53 55 56 55 Woodland group Symbol Page Number Page IIIe-2 53 2 60 IVe-1 55 2 60 IIIe-2 53 2 60 IVe-1 55 2 60 IIe-2 51 7 62 IIe-2 51 7 62 IIIe-1 53 7 62 IIIe-1 53 7 62 IVe-1 55 7 62 IIw-1 52 7 62 IIe-2 51 7 62 IIIe-1 53 7 62 1-2 50 3 61 IIe-1 50 1 60 IIe-2 51 1 60 IIIw-1 54 7 62 IIIs-1 54 6 62 IIw-1 52 7 62 1-3 50 6 62 IIIe-3 54 7 62 IIIe-3 54 7 62 IIIe-3 54 7 62 I-l 50 1 60 IIe-1 50 1 60 IIe-2 51 1 60 IIe-2 51 1 60 IIIe-1 53 1 60 1-2 50 5 ■62 IIe-1 50 7 62 IVw-1 55 7 62 IIIe-3 54 7 62 IIIw-2 5U 7 62 IIIw-2 54 7 62 IIw-2 53 7 62 IIIe-3 54 7 62 IIIe-3 54 7 62 IIIe-3 54 7 62 IIIw-2 54 7 62 IIIe-3 54 7 62 62 60 60 60 GUIDE TO MAPPIHG UHITS For a full description of a mapping unit, read both the description of the mapping Other information Is given in tables as follovis: Acreage and extent, table <+, p. 1 Estimated yields, table 5, P- 57- unit and the soil series to which the mapping unit belongs. Engineering uses of the soils, tables 6, 7, and 6U through 8l. 8; iO itt) u? iijj 11 iB UJB? UjC iij;j IHB 1!7« 1J7D 1?7B2 1!7C 1?7C? i?8b i?ft: 1?PC2 l?8l) 11? \n i]i«:2 Mappinfj unit Cisne silt loam lloyleton silt loam, to 2 percent slopes - Hoyleton silt loam, 2 to 5 percent slopes lloyleton silt loam, 2 to 5 percent slopes, eroded Blair silt loam, 5 to 9 percent slopes, eroded Blair soils, 5 to 9 percent slopes, seyerely eroded Hickory loam, 7 to 12 percent slopes Hickory loam, 7 to 12 percent slopes, eroded Hickory soils, 7 to 12 percent slopes, severely eroded- Hickory loam, 12 to l8 percent slopes Hickory loam, 12 to l8 percent slopes, eroded Hickory soils, 12 to 25 percent slopes, severely erodefl Hickory loan, l8 to 30 percent slopes Hickory loam, 30 to 60 percent slopes - — Ipava silt loam lierrick silt loam Ebbert silt loam Virrlen silty clay loam Hadford silt loam Racoon silt loam Cowden silt loam Oconee silt loam, to 2 percent slopes Oconee silt loam, 2 to H percent slopes Oconee silt loam, 2 to U percent slopes, eroded Oconee silt loam, l4 to 7 percent slopes Oconee silt loam, 1) to 7 percent slopes, eroded OTallon silt loam, S to U percent slopes Harrison silt loam, to 2 percent slopes Harrison silt loam, 2 to It percent slopes Harrison silt loam, 2 to U percent slopes, eroded Harrison silt loam, U to 7 percent slopes Harrison silt loam, I4 to 7 percent slopes, eroded Douglas silt loam, 2 to 1| percent slopes OMglas silt loam, U to 7 percent slopes Houglas silt loam, 1+ to 7 percent slopes, eroded tlouElas silt loam, 7 to 12 percent slopes Starks silt loam Camden silt loam, 2 to U percent slopes Camden silt loam, H to 7 percent slopes, eroded Shlloli silty clay loam Shiloh silt loam, overwash Stoy silt loam, to 2 percent slopes !^toy silt loam, 2 to U percent slopes Heir silt loam Hosmer silt loam, 2 to U percent slopes Hosmer silt loam, ll to 7 percent slopes Management V/oodland scribed group group Map on page Symbol Page Number Page symbol 111 IIIw-1 •yh 7 62 2ll|C2 27 27 IIw-2 Ile-lt 53 52 7 7 62 62 2lltC3 2lltD2 27 Ile-lt 52 7 62 21Ud3 12 IIle-1 53 3 61 250C 12 IVe-1 55 3 61 250C2 2U IIIe-1 53 1 60 25OD 2U lIIe-1 53 1 60 250D2 ?.k IVe-1 55 1 60 25OE 2h IVe-1 55 1 60 252 2k IVe-1 55 1 60 256C2 25602 2I4 VIe-1 55 1 60 257 2lt VIe-1 55 1 60 258b 2U VIIe-1 56 1 60 258C2 29 1-2 50 7 62 287 22 1-2 50 7 62 30U 19 IIw-2 53 7 62 U02 "tS IlM-1 52 7 62 1+51 37 i7 1-3 50 6 62 581B IIIv;-l 51* 5 62 58IB2 17 si IIw-2 IIw-2 53 53 7 7 62 62 58102 583A ^2 Ile-U 53/ 7 62 583B Ile-U 52 7 62 583c IIIe-2 53 7 62 58302 32 IIIe-2 53 7 62 583D2 3lt He- 3 52 2 60 586 20 I-l 50 7 62 587B 20 IIe-1 50 7 62 991 20 IIe-1 50 7 62 992B 20 IIe-2 51 7 62 99 3A 20 IIe-2 51 7 62 993B2 IB IIe-1 50 7 62 99UA 18 IIe-2 51 7 62 99'tB 18 IIe-2 51 7 62 99482 18 IIIe-1 53 7 62 99l(C2 UO IIe-1* 52 5 62 995 13 Ile-l 50 1 60 99602 13 IIe-2 51 1 60 38 IIw-1 52 7 62 996D2 38 IIw-1 52 7 62 - uo IIu-2 Ile-l* IIw-1 53 52 52 3 3 U 61 61 61 997r - Uo 997G 146 998F 26 He- 3 52 2 60 Gu 26 IIIe-2 53 2 60 f-: Mapping unit ' page Hosmer silt loam, 4 to 7 percent slopes, eroded 26 iiosmer soils, H to 7 percent slopes, severely eroded — 26 Hosmer silt loam, 7 to 12 percent slopes, eroded 26 Hosmer soils, 7 to 12 percent slopes, severely |eroded- 27 Velma loam, U to 7 percent slopes U3 Velma loam, 1+ to 7 percent slopes, eroded 1*3 Velma loam, 7 to 12 percent slopes •*!* Velma loam, 7 to 12 percent slopes, eroded 1*1* Velma loam, 12 to 18 percent slopes **!* Hai'vel silty clay loam 21 Pana loam, 1* to 7 percent slopes, eroded 3** Pana loam, 7 to lU percent slopes, eroded : 3** Clarksdale silt loam j I6 Sicily silt loam, 2 to 1* percent slopes ; 39 Sicily silt loam, 1* to 7 percent slopes, eroded 39 Chauncey silt loam 13 Landes fine sandy loam ' ■^9 Colo silty clay loam --- -- 1° Lawson silt loam j j30 Tamalco silt loam, 2 to U percent slopes -. Ul Tamalco silt loam, 2 to 1* percent slopes, eroded U2 Tamalco silt loam, 1* to 7 percent slopes, eroded te PUce silt loam, to 2 percent slopes J 36 Pike silt loam, 2 to U percent slopes ^ 3d Pike silt loam, 1* to 7 percent slopes 7 3° Pike silt loam, U to 7 percent slopes, eroded-- 36 Pike silt loam, 7 to 12 percent slopes, eroded- 36 Hokomis silt loam ^^ Terril loam, 2 to 5 percent slopes tJ Cisne-Huey complex ^ Hoyleton-Taraalco complex, 1 to 1* percent sl^pe? 20 Cowden-Piasa complex, to 2 percent slopes— 7 17 Cowden-Piasa complex, 2 to 1* percent slopes, eroded—- 18 Oconee-Tamaloo complex, to 2 percent slopes-- 32 Oconee-Tamalco complex, 2 to U percent slopes--— 32 Oconee-Tamalco complex, 2 to 1* percent slopes, er9aed- 32 Oconee-Tamalco complex, I* to 7 percent slopes, eroded- 33 Herrick-Piasa complex Velma-Walshville complex, U to 7 percent slopes, eroded Velma-Walshville complex, 7 to 12 percent slopes, ^^ eroded pr Hickory-Hennepin loams, 18 to 30 percent slopes — ^« Hickory-Hennepin loams, 30 to 60 percent slopes 2> Hickory and Negley loams, 15 to 35 percent slopes ^5 Gullied land Management Woodland group group Symbol Page Number Page IIIe-2 53 2 60 IVe-1 55 2 60 IIIe-2 53 2 60 IVe-1 55 2 60 IIe-2 51 7 62 IIe-2 51 7 62 IIIe-1 53 7 62 IIIe-1 53 7 62 IVe-1 55 7 62 IIw-1 52 7 62 IIe-2 51 7 62 IIIe-1 53 7 62 1-2 50 3 61 IIe-1 50 1 60 IIe-2 51 1 bO IIIw-1 5I1 7 62 IIIs-1 5'* 6 62 IIw-1 52 7 62 1-3 50 6 62 IIIe-3 5'* 7 62 IIIe-3 5"* 7 62 IIIe-3 51* 7 62 I-l 50 I 60 lIe-1 50 1 W IIe-2 51 1 60 IIe-2 51 1 bO IIIe-1 53 1 60 1-2 50 5 62 IIe-1 50 7 62 IVw-1 55 7 6a IIIe-3 51* 7 62 IIIw-2 51* 7 62 IIIw-2 51* 7 62 IIw-2 53 7 IIIe-3 51* 7 62 IIIe-3 5li 7 62 62 62 IIIe-3 5I1 7 IIIw-2 51* 7 IIIe-3 51* 7 62 IIIe-1 53 7 62 60 VIe-1 55 1 VIIe-1 56 1 60 60 VIe-1 55 1 — - "' 1 89°40 _SANGAMON "le" T. 12 N. T. 11 N. T. 7 N. R. 2 W. -39°00 MADISON I CO I R. 5 W.l — "Tzr U S DEPARTMENT OF AGRICULTURE SOIL CONSERVATION SERVICE UNIVERSITY OF ILLINOIS AGRICULTURAL EXPERIMENT STATION GENERAL SOIL MAP MONTGOMERY COUNTY, ILLINOIS m SOIL ASSOCIATIONS Virden-Hernck association. Ddrk-colored, poorly drained and somewhat poorly drained soils on upland flats _ Hernck-Harrison association: Level to sloping, dark- ^^fl colored, somewhat poorly drained to moderately well drained ^^ soils Oconee-Douglas-Pana association: Strongly sloping to ■>^T| gently sloping, dark colored and moderately dark colored, l^^<| well-drained and somewhat poorly drained soils on ridges and knolls Herrick-Piasa association: Level, dark colored and moderately 4 I dark colored soils that are on upland divides and that have a moderately slowly or very slowly permeable subsoil ^ Cowden-Piasa association: Level, moderately dark colored f^i soils that have a slowly or very slowly permeable subsoil m m. Cisne-Hoyleton-Huey association: Level to gently sloping, ^1 light-colored to moderately dark colored soils that have a slowly permeable or very slowiy permeable subsoil Oconee-Veima-Tamalco association: Nearly level to strongly sloping, moderately dark colored soils that have a slowly ' permeable, moderately permeable, or very slowly permeable subsoil Hrckory-Hosmer association: Gently sloping to very steep, 8 I light-colored, moderately well drained and well drained soils on uplands adjacent to streams | =:Lr;:ylji | Lawson-Radford association: Level, dark-colored, somewhat | ^=^?^ | poorly drained soils on flood plains February 1968 m U. S. DEPARTMENT OF AGRICULTURE SOIL CONSERVATION SERVICE tVIONTGOMER SOIL LEGEND WOR Highways and road A number shows The soil type or complex. A cc pital letter, A, B, C, D, E, F, or G, shows the slope. Most symbols without o slope letter are those Dual . of neorly level soils, but some ore fo r land type s, for example. Gullied land, that have o considerable range Df slope. A finol number, 2, after the Good motor slope letter indicates on erod sd soil; 3, a severely eroded soil. A "+" at the end of the symbol indicates on overwoshed soil. Poor motor Trail SYMBOL NAME SYMBOL NAME Highway markers 2 Cisne silt loom 214C2 Hosmer silt loom, 4 to 7 percent slopes, eroded 3A Hoylet-on silt loam, to 2 percent slopes 214C3 ■Hosmer soils, 4 to 7 percent slopes, severely eroded National Interst 3B Hoyleton silt loam, 2 to 5 percent slopes 214D2 Hosmer silt loom, 7 to 12 percent slopes, eroded 3B2 Hoyleton silt loam, 2 to 5 percent slopes, eroded 214D3 Hosmer soils, 7 to 12 percent slopes, severely eroded u. s. 5C2 Blair silt loam, 5 to 9 percent slopes, eroded 250C Velmo loom, 4 to 7 percent slopes 5C3 Blair soils, 5 to 9 percent slopes, severely eroded 250C2 Velma loam, 4 to 7 percent slopes, eroded 8D Hickory loam, 7 to 12 percent slopes 250D Velmo loom, 7 to 12 percent slopes State or county 8D2 Hickory loom, 7 to 12 percent slopes, eroded 250D2 Velmo loam, 7 to 12 percent slopes, eroded 8D3 Hickory soils, 7 to 12 percent slopes, severely eroded 250 E Velma loom, 1 2 to 18 percent slopes Railroads BE Hickory loam, 12 to 18 percent slopes 252 Horvel silty cloy loam 8E2 Hickory loam, 12 to 18 percent slopes, eroded 256C2 Pane loam, 4 to 7 percent slopes, eroded Smgle track 8E3 Hickory soils, 12 to 25 percent slopes, severely eroded 256D2 Pono loam, 7 to 14 percent slopes, eroded 8F Hickory loom, 18 to 30 percent slopes 257 Clorksdole silt loom 8G Hickory loom, 30 to 60 percent slopes 258 B Sicily silt loam, 2 to 4 percent slopes Multiple track 43 Ipova silt loam 258C2 Sicily silt loom, 4 to 7 percent slopes, eroded 46 Herrick silt loam 287 Chauncey si It loom Abandoned 48 Ebbert silt loom 304 Londes fine sandy loom 50 Virden silty cloy loom 402 Colo silty clay loom Bridges and cross 74 Radford si It loom 451 Lowson si It loom 109 Racoon silt loam 581B Tomolco silt loom, 2 to 4 percent slopes 112 Cowden silt loam 581B2 Tomolco silt loam, 2 to 4 percent slopes, eroded Road 113A Oconee silt loam, to 2 percent slopes 581C2 Tomolco silt loom, 4 to 7 percent slopes, eroded 113B Oconee silt loam, 2 to 4 percent slopes 58 3 A Pike silt loom, to 2 percent slopes Trail, foot 113B2 Oconee silt loam, 2 to 4 percent slopes, eroded 583B Pike silt loom, 2 to 4 percent slopes 1130 Oconee silt loam, 4 to 7 percent slopes 58 3C Pike silt loom, 4 to 7 percent slopes Railroad 113C2 Oconee silt loom, 4 to 7 percent slopes, eroded 583C2 Pike silt loom, 4 to 7 percent slopes, eroded 114B O'FaUon silt loom, 2 to 4 percent slopes 583D2 Pike silt loom, 7 to 12 percent slopes, eroded 127 A Harrison silt loom, to 2 percent slopes 586 Nokomis Slit loam Ferry 127B Harrison silt loam, 2 to 4 percent slopes 587B Terri 1 loom, 2 to 5 percent slopes 127B2 Harrison silt loom, 2 to 4 percent slopes, eroded 991 Cisne— Huey complex Ford 127C Harrison silt loom, 4 to 7 percent slopes 992B Hoyleton— Tomolco complex, 1 to 4 percent slopes 127C2 Harrison silt loam, 4 to 7 percent slopes, eroded 993A Cowden-Pioso complex, to 2 percent slopes Grade 128B Douglas silt loam, 2 to 4 percent slopes 993B2 Cowden — Pioso complex, 2 to 4 percent slopes, eroded 128C Douglas silt loam, 4 to 7 percent slopes 994A Oconee— Tomolco complex, to 2 percent slopes 128C2 Douglos silt loam, 4 to 7 percent slopes, -eroded 994B Oconee— Tamalco complex, 2 to 4 percent slopes R. R. over 128D Douglas silt loam, 7 to 12 percent slopes 994 B 2 Oconee — Tomolco complex, 2 to 4 percent slopes, eroded 132 Storks silt loom 994C2 Oconee-Tomalco complex, 4 to 7 percent slopes, eroded R. R. under 1348 Camden silt loom, 2 to 4 percent slopes 995 Herrick — Pioso complex 134C2 Comden silt loom, 4 to 7 percent slopes, eroded 996C2 Velma— Walshvil le complex, 4 to 7 percent slopes, eroded 138 Shiloh silty clay loom 996D2 Velma— Wolshville complex, 7 to 12 percent slopes, eroded Tunnel 138 + Shiloh silt loom, overwosh 997F Hickory — Hennepin loams, 18 to 30 percent slopes 164A Stoy silt loam, to 2 percent slopes 9970 Hickory — Hennepin looms, 30 to 60 percent slopes Buildings 164B Stoy silt loom, 2 to 4 percent slopes 998 F Hickory and Negley looms, 15 to 35 percent slopes 165 Weir silt loom School 214B Hosmer silt loam, 2 to 4 percent slopes Gu Gullied land 214C Hosmer silt loam, 4 to 7 percent slopes Church Station Mines and Quarne Mine dump Pits, gravel or oth Power line Pipeline Cemetery Dams Levee Tanks Well, oil or gas .. SANGAMON i*^® COUNTY^ I MONTGOMERY COUNTY, ILLINOIS SCALt IN MU.l.S L-^-J I I ' I U S DEPARTMENT OF AGRICULTURE SOIL CONSERVATION SERVICE MONTGOMERY COUNTY, ILLINOIS , I7,..,remii-.li,r.« Haf.l.,0.. .III l«..m. (H«:'p M«rH..n silt locim, i^Fo lll loom, '1 10 /p Dout|lo-i lit Inu'ti, '^10 -tp OoUflld!. ill loam, '1 10 / (. Oourilon Ut loam, *! to / p DovllOf. III lociii. 7 in 13 ^latU-i n\ 1 \nain ComJun lU loom, ?lo -Ip ComJon til locim, llo /p Shllol. fll ly cloy loiim Sh.loli Dl 1 loam, uvortvuiili Slof '.ll> loam, 10 2 poieu Sioy nlli loom, 2 lo '1 po'cu W..|r rilh loam :cni ilopas, uroded kppi, eroded WORKS *ND STRUCTURES Ann Sicily '.111 loom, y (0 '1 p pfcprii ^kpt^ MuHiDie ^WC,- 'ynily ■^ill loom, 'I In / p Pr..^-,.. slopt".. ^ro.Je.J w Liiiii)(.-i (inu ^unciy loiim Abando .»i? '".L.l.j ..ilry ,:(9 KV T.imolco -.ill loom, •! to '^3\ Trail, to '>9-"in Piko illl loom, 2 15 -Ipe sajc PikL- -.ill loom, '1 10 7 pe teenr ilopes Railroad '>8Jc"./ PlW< Mil bom, 'li» ;po rcwnl slopoi, eroded '.fi^O? Ptko '.III loom, 7 to l?p pfcont slopes, cmdod 'iSf) Nokomis --.111 loam r.?t./ '.avfj Tornl loom, 3 lo ^ porec n1 Jlopes ■Jl?!! Hoyl«1on-VomdL'«'omp OH, 1 To '1 pptct-ni ilopL's 7';3ft Cowdef.-Pio--.Q>;omplox to 2 p»rc<''>l -Jopifi. W3iW roivJon-Pia^o compli^n 2 10 'I porcuni ^lopi?5, orodod 99.1A OcnrH'O-lomolco compi ■, 10 2 perconi ilopos 99iIU Oconon-romoko compI 4 ?io 4 portent tilopes R R 59^ B? Oconi-o-Toinoko compt M ?to 'Ipercenl slopes etodt-d W4(:3 Oeonpo- romokrt iiompl H, '1 10 7 pereenr slopes, eroded R. R u Hfrnck-Plaso complo- '596C? Volmu-Wolshvlllo eomp "t slopes |)'V7G Ilkkorv-Mfnnepln loom , 30 lo bOpi^rccnt slopes Buildings WHr Hickory ond Nogloy loon ., 15 TO 35 portent slopes Pits, gravel Pipeline Cemelety n D O ILLINOIS AGRICULTURAL EXPERIMENT STATION CONVENTIONAL SIGNS BOUNDARlE N., ,na,c f slale Cou nty B!5 e.,.„c " Lan d grar t + H streams, s.ngle-ltne Perennial -^^ ~~~~^ ^- — Intermittent Crcissable with Ullage implements ---■ ' -^ ^~~- Noi Cfossable witti tillage , Perannlal QaU?) Qy Intermiltent ^— - — -'"' Spring Q Wet spot V *"""' '" ^. -_,.,— ..^ Drainaee end — - ^.._. — •--, RELIEF Escarpmenis Bedrock _ '" -■"■••>., Other - "'""" """""""i'l""" Prominent peak O Large Small ^'3 SOIL SURVEY DATA Gravel Slony. very stony Rock outc'OPS Chert Iragmenis Clay spot Sand spot Gumbo or scabby spot Made land Severely eroded spot Blowoul.wind efosion /2^SC2 J Soil moo cofntfuetcd 1766 by Conogrophic Oi'' ^ Co^-Vrvotion Sefv.ce, USDA. from 1962 « Soil Lonvcrvonon .w. , ._...,„ fiUn. OUNTY, ILLINOIS ILLINOIS AGRICULTURAL EXPERIMENT STATION vj'^ND STRUCTURES o o o -I 1 ( 1 1- -H H M H H- -I H — H — I I -I 1 1 1- -4 1 1- CONVENTIONAL SIGNS BOUNDARIES National or state ^^^^_ _ _ ^^^^_ County - ___^^ ^ ^^^^^ Reservation . . Land grant . . . . Small park, cemetery, airport .- Land survey division corners I I __L_ DRAINAGE Streams, doubie-line Perennial Intermittent - — "' " ■^-_."'.'— — ' Streams, single-line Perennial — "^ ' ^' Intermittent Crossable with tillage implements -^■' ' — ^ ~~~~ Not crossable with tillage .. implements -^^'- ^ ' Unclassified ^■•■■^ CANAL Canals and ditches Lal"'> the time ^Oi * SOIL SURVEY DATA Soil boundary and symbol Gravel Stony, very stony Rock outc'ops Chert fragments Clay spot Sand spot Gumbo or scabby spot Made land Severely eroded spot Blowout, wind erosion Gully (J^ (0

C3 NUMBER 102 3 000 Feet MONTGOMERY COUNTY, ILLINOIS - SHEET N i (Joins sheef 96) R. 3 W. (Joins sheet / 12) V2Mile _i Scale 115 840 l_ MONTGOMERY! COUNTY, ILLINOIS - SHEET NUMBER 103 Scale 1:15 840 MONTGOMERY COUNTY, ILLINOIS - SHEET NUMBER 104 Scale 1.15 840 ? NUMBER 104 3000 Feet MONTGOMERY COUNTY, ILLINOIS - SHEE' R. 2 W. 214B (Joins sheet 1 14) VzMile _j Scale 1:15 840 l. MONTGOMERY (cOUNTY, ILLINOIS — SHEET NUMBER 105 Scale 1:15 840 MONTGOMERY COUNTY. ILLINOIS - SHEE NUMBER 106 (1mm ilwol 114 Scale 115 840 r NUMBER 106 3 000 Feet MONTGOMERY COUNTY, ILLINOIS — SHEET N (Joins sheef 100) R. 5 W. ( J0//1S iheei J ) 6) VpMile _i Scale 1:15 840 l_ MONTGOMERyI county. ILLINOIS — SHEET NUMBER 107 MONTGOMERY COUNTY, ILLINOIS - SHEETI NUMBER 108 Scale 1:15 840 l_ NUMBER 108 164B 3 000 Feet MONTGOMERY COUNTY, ILLINOIS — SHEET T 214C2 R- 4 W. ViMile _i Scale 1:15 840 l. MONTGOMERY COUNTY. ILLINOIS - SHEET NUMBER 109 CJo.ns sheet 117) Scale 115 840 MONTGOMERY COUNTY, ILLINOIS - SHEET NUMBER 110 NUMBER 110 ¥^151 3 000 Feet MONTGOMERY COUNTY, ILLINOIS — SHEET "■" (Joins sheef 104) 993A R. 3 W. BOND COUNTY V^Mile _i Scale 1:15 840 i_ MONTGOMERY COUNTY. ILLINOIS — SHEET NUMBER 111 BOND COUNTY Scale 1:15 840 MONTGOMERY COUNTY, ILLINOIS - SHEET NUMBER 112 N (lo.n: -.heel 104) BOND CDlNlv Scale 1:15 840 NUMBER 112 3 000 Feet -1 I MONTGOMERY COUNTY, ILLINOIS - SHEET R. 2 W. BOND COUNTY ViMile _i Scale 1:15 840 l_ MONTGOMERY COUNTY, ILLINOIS - SHEET NUMBER 113 ^Mile Scale 1:15 840 MONTGOMERY COUNTY. ILLINOIS - SHEET @ NUMBER 114 i'lND I'Ol-NTV Scale 115 840 NUMBER 114 3 000 Feet MONTGOMERY COUNTY, ILLINOIS — SHEET (Joins sheei 108) R. 5 W. MADISON COUNTY ViMile MONTGOMERY COUNTY, ILLINOIS - SHEET NUMBER 115 Scale 1:15 840 MONTGOMERY COUNTY, ILLINOIS - SHEET NUMBER 116 1 Scale 115 840 NUMBER 116 250E. 8D3 3 000 Feet MONTGOMERY COUNTY. ILLINOIS - SHEET NUMBER 117 inn Scale 1:15 840 _SANGAMONl ^ BOUNTY ^ | T. 12 N. COUN' R. 2 W. MADISON 1 CO I R. 5 W.l — 39°00 U S DEPARTMENT OF AGRICULTURE SOIL CONSERVATION SERVICE WORKS AND STRUCTURES ^rgllw^vs and roads Good motor Poor motor Abandoned Bridges and c Grade R. R. ov« R. R. un< Tunnel Buildings School Church o o o 1 Tiail, loot • Ferry Ford ,J / . — -/- Escarpmenis Bedrock Large Small Tan Wei .0,1 • ® Not cr Contai the tir ossable « (Ih til aee e ns water most o1 MONTGOMERY COUNTY, ILLINOIS ILLINOIS AGRICULTURAL EXPERIMENT STATION SOIL SURVEY DATA Soil boundary and symbol ...:.... Stony, very stony Chert fragments Sand spot Gumbo or scabby spot Made land Severely eroded spol „ Blowout, wind erosion Gully ru\/\f\r\r\j SOIL LEGEND /■^258C2 ) 8D2 Hickory loam, 7 (0 12 p 8D3 Hickory soils, 7io 12f 8E Hickory loam, 12 to 16 8E2 Hickory loam, 12 to 18 8E3 Hickory soils, 12 to 25 8F Hickory loom, 18 to 30 8G Hickory loom, 30 to 60 113A Oconee 1136 Oconee 113B2 Oconee 113C Oconee 113C2 Oconee 114B O'Folio 127A Horriso 127B Horrisor 127B2 Horriso 127C Horriso 127C2 Horrisor 1288 Doug 1 OS i2ac Douglos 128C2 Douglos 1280 Douglas 132 Srorks s 134B Camden 134C2 Comder. 138 Shiloh s 138+ Shiloh s 164A Sroy sil 164B Sioy sil 165 Wetf sil 2t4B Hosmer 21 4C Hositier SYMBOL 214C2 214C3 214D2 2I4D3 250C 250C2 250D 250D2 250E 252 451 saiB 581B2 581C2 533A S83B 583C 58X2 583D2 586 5876 991 992B 993A 993B2 99 4 A 994B 994B2 994C2 995 »nr slopes, eroded ilopes, sever«ly eroded :en( slopes, «rodad slopes, severely orcded Soil mop constructed 1966 by Coriogrophic Dl Soil ConservotJon Service, USDA, from 1962 o phorographs. Conlrolled mosolc based on llln MONTGOMERY COUNTY, ILLINOIS SCALE IN MILES HECKMAN IXI BINDERY INC. |b| APR 97 Be^a-To-P.^ N.MANCHESTER,