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To renew call Telephone Center, 333-8400 UNIVERSITY OF ILLINOIS LIBRARY AT URBANA-CHAMPAIGN L161 O-1096 CONTENTS PACE UPWARD TREND IN ILLINOIS ACRE- YIELDS 87 BETTER VARIETIES ONE REASON FOR BETTER YIELDS 87 SOIL TREATMENT ON TEST FIELDS 88 HIGHEST YIELDING VARIETIES IN ILLINOIS TESTS 90 Northern Illinois 90 Central Illinois 93 Southern Illinois 93 CHOOSING A VARIETY TO GROW 98 Capacity for High Yields 99 Resistance to Prevalent Diseases 99 Milling and Baking Qualities 103 RECOMMENDED SOIL TREATMENT FOR WHEAT.... 103 RECOMMENDED PRACTICES IN GROWING WHEAT.. 104 ECONOMY OF PRODUCTION is the aim of state and national agencies in their search for improved varieties of all farm crops. For wheat this means varieties that will give better acre- yields of high-quality grain with greater certainty thru varying seasons. When reduction in total yield of grain is desired, that can be economically obtained only thru reduction of acreage. Urbana, Illinois December, 1939 Publications in the Bulletin series report the results of investigations made or sponsored by the Experiment Station Winter Wheat Varieties For Illinois By GEORGE H. DUNCAN, W. L. BURLISON, BENJAMIN KOEHLER and O. T. BONNETT' Upward Trend in Illinois Acre-Yields F THE FARM CROPS produced in Illinois, wheat ranks fourth in value. During the last thirteen years, 1927-1939, about 95 percent of the Illinois crop was winter wheat and 5 percent was spring varieties. The acreage of spring wheat varies con- siderably from year to year, being largest in seasons when winter wheat is killed by an unfavorable winter or when wet fall weather prevents seeding the desired acreage of winter wheat. While the average acre-yield of winter wheat for the United States as a whole has been slightly downward over the last forty-four years, Illinois acre-yields have trended upward (Fig. I), having increased from a little over 11 bushels an acre for the four-year period 1895- 1898 to a little less than 17 bushels for 1935-1938. For the country as a whole the correspondingyields were 14.7 bushels and 12.9 bushels. Better Varieties One Reason for Better Yields Factors contributing to this rise in the acre-yield of winter wheat in Illinois are numerous and difficult to analyze. The use of land better fitted for wheat may have been partly responsible for this rise in yield, but varietal improvement must be credited with having played an important part in the increase. That variety trials at the Illinois Station have paved the way for the introduction of better-adapted varieties into the state is shown by an analysis of the yields on test plots on the Agronomy south farm at Urbana over the last thirty-five years. In the Southwest rotation (corn, oats, clover, and wheat) the variety Turkey has been included during the entire period. Many other promising varieties have been introduced into these trials, and after being tested long enough to demonstrate their producing capacity have been dropped in favor of other promising sorts. I GEORGE H. DUNCAN, Chief in Crop Production; W. L. BURLISON, Chief in Crop Pro- duction and Head of Department of Agronomy; BENJAMIN KOEHLER, Chief in Crop Pathology; and O. T. BONNETT, Assistant Chief in Plant Genetics. 87 88 BULLETIN No. -460 [December, 12 - 1895 1899 1903 1907 1911 1915 1919 1923 1927 1931 1935 1898 1902 1906 1910 1914 1918 1922 1926 1930 1934 1938 FOUR-YEAR PERIOD FIG. 1. YIELDS OF WINTER WHEAT BY FOUR- YEAR PERIODS FROM 1895 TO 1938 Factors which tend to cause wheat yields to climb upward are improvement in varieties, better cultural methods, and increase in productivity of the soil. Factors which pull down the average yields are declining soil fertility, increase in prevalence of diseases and insects. During the first five-year period the five best varieties yielded 4.4 bushels an acre less than Turkey (Fig. 2). In the last five-year period the five best varieties averaged 4.7 bushels an acre more than Turkey a 9 bushel gain during thirty-five years. Soil Treatment on Test Fields DeKalb. The soil on the DeKalb field in northern Illinois consists of a number of types, all of which are common to the region. Since 1924 the rotation has been corn, spring grains, wheat, and soybeans. This field has long received soil treatment. During the past eight years all plots have been given a uniform application of manure at the rate of 8 tons an acre once in each rotation and an application of rock phosphate when soil tests showed a need for phosphorus. Urbana. Experiments with wheat at Urbana in central Illinois have been conducted on Muscatine silt loam soil in a rotation of corn, WINTER WHEAT VARIETIES FOR ILLINOIS 32 1934 1938 FIVE-YEAR PERIOD FIG. 2. YIELDS OF TURKEY AND FIVE OTHER BEST VARIETIES OF WINTER WHEAT IN DRILL-PLOT TRIALS AT URBANA, 1904-1938 For the first four years after it was introduced into the tests, Turkey was the highest yielding variety ; but since then the better new varieties have exceeded Turkey. It is evident that distinct improvement has been achieved in the new varieties. oats, clover, and wheat. In the early years of the tests one end of half the plots received residues and rock phosphate ; the other end received residues, rock phosphate, and limestone. One half of the other plots received manure and rock phosphate; the other end of these same plots received manure, rock phosphate, and limestone. Beginning in 1934 the residues have been omitted and manure substituted, so that now all plots receive essentially the same treatment except that to one end of each of them ground limestone has been applied while the other half has received no limestone. Alhambra. The soil on the Alhambra field in southern Illinois is Putnam silt loam with numerous "slick" spots. Wheat is now grown in a rotation of corn, oats (sweet clover), soybeans, and wheat (sweet clover). All plots from the very beginning of the wheat trials have been fertilized with crop residues, ground limestone, and rock phosphate. 90 BULLETIN No. 460 [December, Highest Yielding Varieties in Illinois Tests The ability of the varieties included in the Illinois tests during the past fourteen years to produce grain under the conditions of these tests is shown in Tables 1, 2, and 3. Attention is called to the fact that the soil on these fields is free from mosaic virus. Northern Illinois On the DeKalb field in northern Illinois, Kawvale, loturk, Min- turki, Purkof, Illinois 2, Hardy Northern, and Kanred are found at the top of the list, with the following comparable average yields. Other varieties follow these so closely, however, as to leave a very small margin for choice on the basis of yields. Bushels per acre Bushels per acre Kawvale 34.0 Illinois 2 29.7 loturk 32.4 Hardy Northern 29.7 Minturki 31.1 Kanred 29.7 Purkof 30.4 Kawvale is a Kansas wheat which has an excellent yield record in Illinois. For this reason a few Illinois farmers are growing it even tho its grain is only of medium quality for breadmaking. It is sus- ceptible to mosaic disease, however, and sometimes shatters badly while waiting for the combine. loturk, a product of the Iowa Station, is a Turkey type which in addition to a high yield record has good baking quality. This variety is not extensively grown in northern Illinois, however, because of its weak straw. It is also very susceptible to the mosaic disease. Minturki is grown to a considerable extent in northern Illinois. It is a consistent producer and while not outstanding in any given char- acter, neither is it distinctly inferior in any respect. This wheat was developed at the Minnesota Station. Purkof, altho only medium in breadmaking quality, is a rather popular variety because of its winter-hardiness, its moderate resistance to lodging, and its freedom from awns. Purkof is very susceptible to mosaic and black stem rust. Illinois 2 is the highest yielding strictly soft wheat that has been tested on the northern Illinois field. Because of its extreme suscepti- bility to the mosaic disease, however, it may be expected to decline in acreage. It will be continued in future variety tests merely as a check on the performance of new mosaic-resistant strains which have been selected from it. Hardy Northern, altho a high-yielding variety in northern Illinois 1939] WINTER WHEAT VARIETIES FOR ILLINOIS 91 ft * - -r^OC ON 00 . . . .PC . . -H to ON -00 ' 1/5 (N t-^ ON O ^ -^ -^frro ON t^ PS PS PS -PC OOOO'-I 1O cs fs i PC rs fsj .(M -CS^ - o> NO PS * ** O 1 PS r/5 . ^ ^ fsj . (^ CS CS M CS fs) \O vO fS O \O fv] IO O ^ CN -(N - -fNCN ^H . - \o t^. f*5 . PS . . . . .0 >\ Ov l/> \fl O ^ O 10 t^ * f} f*5 rf rj- ff) 00 f*3 OC ^ PC -PC f*5 ^ o 10 . PC . . - - *- PC PN 3 >1 >v i ON * PSPS PNPNPNPS OOPC OOOOt- CS -OO^H .^M " - ^i PC i c ON PC S !!Z ! *H .^H t^ ON "* 00 . -0-H * 4 * 5 ON ^-t r* *o oo \o 00 vC OC \O -00 ro -fOf^r* 1 ; . (s . -oo O 1/5 vO PC PC -PCNO -PCPC > ON oo o> r*! to 10 10 10 -Ov 0^0 Tf . -PCI/5 - * . -Tf EI ini/J^ON 100 -tfS^i ON-H -NOIO 4 ^ ON O -PCPNPN PS O ON PC OO 00 PC PS PN PS PS PN PN -PS(S ~t -PC PS -PN o -o 2 PC ON IO OO PN 00 PC 00 PCPC O Tfr>: .,* : : 3J ;> ON -PC Tf OOOOO a ps --PCO Oio --OPC O -r~ 5 C' o "aJ J "5 ON 00 -PCPC PSPS PN ON ON F-" PS PS PSPS PNPCPC OOPC -ONO OON -OOO O * PC PN H i O> 'PNOONOO PS PS'H . -PNPS PN PS -00 t- <- 01 CT> 0> 01 01 00 N CM CM N CM C C oo oo oo oo oo t- e- OJ CM CM CM CM CM CM .Si .1! PS M C : 3 1^^^ g* 3*3.2 >>"S jr )* +* vi OTI )-> |3.S^.sl 11 :g&l-d 8 g_: E^j= 5 Ilred 5 Illinois Winter Fife. 7 lowin 8 Harvest Queen .... 9 Michigan Amber. ... Ukrainka 1 Cheyenne 2 Minhardi 3 Duffy 4 Blackhull 5 Illinois 84 6 Nabob 7 Red Rock (3 92 BULLETIN No. 460 [December, C J jgj T w 5 fl *t * -tfl tsro .- a ^?S (S 3 - . . . .(SJ . . "5 ts ts 8 ti 11 .... ....<.. m s * 1 2 !g 1 1 <* ts o 4J ^ * J "5 C "O ^ 2^11 o W5 -o j H ]|| CN . . . .\O \o _g rt ^ 2 C! ooo -10 O* '5 u > .2 1 ^ 3i-*li *** oo S ' * v 5 "3 ^ i-3 c "5 .Q M f 2 ^" o J|jJ! M3 (S tn ll^la o i N ^ 5- 1 ^ ) * w '" "5 ^ K; c > T ^ >. a cs >o pliii ..,.... -tS -H "2 "S rt ^ "*" --O ts . . -vO . . .Tt -tsfj 5 .2 ^ ^ 5 ' c M < co H T-H u> e N CT> . = 000 v c 3 'o M fe aT a; f" -o $ MMeocopacvie* uuooo 4) Iglxli fj Cd fri |^ hfl fti C -^ f~" ' *J ^ ^* rt <<= ->n 1) 1) -O ' ' eg ' ' iiiyl ^ ^ ^.f" 1 j- 2 | ON ~0 3 E ; : ; (- : : : B : Jl.38S 111*111 Srt-g-S. : :4 .n ^^' :=2 > is.2|i i _; 3 E 4) UUtaHU < The way in year it was grown, (42.4 bushels) is 11 parable average yie and divided by the entire period is the 1939] WINTER WHEAT VARIETIES FOR ILLINOIS 93 and one possessing good breadmaking quality, is not grown to any extent, perhaps because of its late maturity. Kanred is another variety of the Turkey type. It is not grown very extensively in northern Illinois, being excelled in acreage by Wisconsin 2, which has a yield record next to it. Central Illinois In central Illinois on the Urbana field, Kawvale, Tenmarq, Brill, Wabash, and Duffy rank highest on the basis of yield: Bushels per acre Bushels per acre Kawvale 42.7 Wabash 40.7 Tenmarq 41.5 Duffy 40.1 Brill 40.8 Thus Kawvale has demonstrated its high-yielding capacity on this field as well as at DeKalb. In spite of its susceptibility to mosaic disease and the ease with which it shatters, some wheat growers have introduced it in this part of Illinois. Tenmarq is another high-yielding variety originated at the Kansas Station. Excellent in breadmaking quality, its greatest weakness is its extreme susceptibility to the mosaic and scab diseases. Brill has a very hard-textured grain which is rated high for bread- making. It is medium in resistance to mosaic and to scab. The great- est weakness of Brill is its tendency to lodge when grown on fertile land. It was developed at the Illinois Station. Wabash is a promising variety for land infected with the mosaic virus because of its resistance to this disease. It is also remarkably resistant to leaf rust. Wabash has long straw, and on fertile land has a tendency to lodge. It is a product of the Indiana Station. Duffy is an awned semihard variety carrying considerable resist- ance to the mosaic disease. It is best adapted to the central part of Illinois ; but as soon as new mosaic-resistant strains are available, the production of Duffy will likely decline. Southern Illinois At Alhambra in southern Illinois seven varieties Fulcaster, Brill, Nabob, Red Sea, Purdue 1, Michigan Amber, and Wabash are in the top group with respect to yield: Bushels per acre Bushels per acre Fulcaster. 26.5 Purdue 1 23.9 Brill 24.8 Michigan Amber 23.7 Nabob 24.2 Wabash 23.7 Red Sea 24.1 (Turn to page 98) 94 BULLETIN No. 460 [December, s H 'a? u^ S^j rt s O) (/) -C Q g a m JH ~~ Q J w < Z < cc CSi E3 CO f*5 CO co co fS CN (S co CS -CO -co -CO fS -co CS co es co fft co fS ^ O C^ ' ^ l* H ^*CS -O Ov ^^ '/)OO GO -^H -O ON*O *O^^ H O^* \O 10 ^O ^ t- rj* f> (S - -i/i r*5 ro cs rt< -^* - o\ 10 . r* *-< 00 O : : : : :9^ ^ : :t ^ f*5 fO fi f) ^ <*3 f*5 CO -^ coco co fO co co fO CO 'CO I B_ . M ^ c-xnoor- imiM o> r> in co N PI CM.noot~oeoc-ov ilo-r- fa~4OOoao> oe oo oo oe oe oo oo oo oo oo oo c- c- c~ c- c- r- | ::::::::::: :d : 3 :: H O*-CS'''"f-! "" Cfli M p2--.---c "7 a v :::::: ^ :::: I ^_^ :-: :::<::::: ;po : ; : : : * .ffil!il I! its cso 9 ' CM CM " 10 CM 00 Ov *O Q* CS fS CM -CS -00 O <> ' ^ " CM -10 M c * o s> tow -oo ooo a ::::::: ::::::: ::::::: :::::: 2 Ov CM -*-* -^ . tOTj. . e or twc ;'H" ' n ' \l * fS CM 0> rown or -o CM 00 * * O irieties g Ov HCM -O -H WJTt .^. . - 3 V 2 " " O, 4)- c; > ^t ^^eocoeoraco coroMCOraraco COCOMCO^OMCO cocaiCQCQC ''S~c * ^ J a; bo OJ 'C ^^ BULLETIN No. 460 [December, s-3 ll > s w CQ t f"*'OOO v O \O Tf t- ps| ^ 00 vO^< '00 CN T* I/} -to ^* CN -O VO - ~- I/) -O-* -00 -T* -TjiCSmtS ^H * -O CM cs O 00 <*3 -00 O* 00 -H -O -f*3Ocs .<*> . -rDr^rOP-ltN CM (S CS -P- O * -r g ?. " 1 " )< ?>>> CM CM CM CM CM CM CM CM CM CM CM CM CM CM CM CM CM CM CVJ CM CM o rt I JB ' 1 :J JidiiJig ^Sa::^ ^ -s3a-g 13x5^5 -3 S*fl l?l?jii Eflfifl siiJiil oc ^ o o 1939] WINTER WHEAT VARIETIES FOR ILLINOIS 97 O> :*;::: Ov 00 5 ts *~ * o -o 0) -CS fS CS f) 1O 0) tS . . . rt s 00 ts . . -o * m tS . ..!/} 00 <*5 ..-cvj.. tS $ 2 I 3 ? <*> . .0 cs * ...00-- -O tS ..-04-- fS H O * 2 P*) tses in vo CO fO a 2 i 2 1 2 a^t-H oo -o o\ a 2 ^ h vO '00 oo j 8 years or -l/> CM & n v 4 "rt " +* + a lO-'tSOO- . .O t O tS'-tS"- ..(N'<-i- CM fM tS ^ tS CS CM CM CSCM-HtStS-H : ||* d 3 000> !<*< to to in -*t< * CO COCMCMCMoot- CM CM CM CM CM CM CM CM CM CM CM rt -H Varieties : c 1) 'v \\l\\\\ \\l\\\ g ...... ^ ..... rt C...C 1 . qj i-i Ijj| .-... s S ~v ' : "o :S : J e : = : 2 '^ Illllll llltil i 98 BULLETIN No. -460 [December, Over the entire period of the tests Fulcaster has been the highest yielding variety on this field. Because of its awns it has not been grown as extensively as its merit warrants, but with the more general use of the combine it is likely to replace a part of the Fulhio wheat so generally grown in southern Illinois. Fulcaster is resistant to mosaic. Brill, altho a hard wheat, does remarkably well in southwestern Illinois. Nabob has been a consistently high producer on the Alhambra field and is recommended for growing in the central and southern sections of Illinois on mosaic-infected land where the winters are too severe for Fulcaster. It is a product of the Ohio Station. Red Sea is a synonym for Mediterranean. Altho a very good- yielding wheat, this variety does not possess any outstanding char- acteristics which make it popular. Altho Purdue 1 is a soft wheat having good quality and an excep- tionally strong straw, it will probably not be widely accepted by farmers because of its extreme susceptibility to the mosaic disease. It is a product of the Indiana Station. Michigan Amber is a medium-hardy to hardy consistent-producing wheat. It has a stiff straw and carries considerable resistance to mosaic. It is widely grown thruout the central corn belt. Wabash, because of its good yields and its resistance to mosaic disease and leaf rust, promises to be grown extensively in south-central and southern Illinois. Fulhio, while not included in the top-ranking varieties on the basis of yield, is a wheat that deserves its present popularity, because of its good milling and baking qualities and its resistance to mosaic disease. Choosing a Variety to Grow The ideal wheat has not yet been developed or discovered, but there are three qualities that an acceptable variety must possess: (1) capacity for high yields; (2) a high degree of resistance to prevalent diseases; and (3) good milling and baking qualities. Other desirable qualities are winter-hardiness ; resistance to the more destructive insects ; lodging resistance even when dead ripe; short straw and early maturity, as these favor the establishment of companion crops; resistance to shattering when fully ripe ; and adaptation to soil and climate. The merits and faults of the varieties included in the Illinois tests during the past fourteen years are indicated in Table 4 (pages 100 and 101). Careful study of this table and the three yield tables will help a grower to choose the variety best suited to his purposes and his growing conditions. 1939] WINTER WHEAT VARIETIES FOR ILLINOIS Capacity for High Yields 99 Only those varieties should be considered seriously for planting that have given good yields for three or more years ; for wheats differ in their ability to adjust to the varying conditions of different seasons, and one that does exceptionally well one year may not do so the next. Resistance to Prevalent Diseases There are a number of diseases that may from time to time cause significant injury to wheat grown in Illinois. The damage caused by stinking smut is largely determined by the extent to which infection is carried on the seed that is planted and the use of proper seed dis- infectants. Mosaic injury occurs only where the soil carries the FIG. 3. WHERE WHEAT MOSAIC DISEASE HAS BEEN FOUND AND YEAR DISCOVERED That some counties contain much more infected soil than others is certain, altho no farm- to-farm survey has been made. As a rule, infection is more ex- tensive and more persistent on bottomlands than on rolling up- land, but severe losses from wheat mosaic on upland have occurred. infection (Fig. 3). Whether certain other diseases, such as leaf rust, stem rust, or scab will be destructive in a given year depends largely on weather conditions. In fact, nearly all diseases are influenced by environmental condi- tions during some part of the growing period of the plant. Environ- ment can be controlled in part. Wheat, for example, need not follow corn on the same soil. By avoiding this sequence, the chances for 100 BULLETIN No. 460 M 3 X 00 6 S5 t! A y s 11 o| ' > . ^"O ,, UJ ll&S District of state to which adapted ccccccc CCBCBCC c c e e c n e "2 "H S3 d g C C C g g -_ ~_ 1 -- 3 =3 1111111 WOt^WOiX^ w t/5 w i/3 i in w ill lll o o o o o ^^0*0 ^ ^o ^ ^ 33 cfl w ffi en 53 ffi g g c ~ (3 WOOWOWW EEE E O -T3 D ' 1> -.3.3.2 : ."S D D -"S 5 E n EE 3 3 :ssss :> E E 3 ' 3 EEE 333;: ^i E d g c g S3 1=3 1 Eg 85^ d 73 -O T3 ~ T3 T3 O O OT3 o O O ** O O 11 II :s i :o O : :S>o,o; HE SE g g EE 3 3 o '-o o o O -O -a-o 00 o o OO E M ESEE EEEE SEE .2 .2 .52 .2 .3 3,3 _3 .3.3_3 332 T3 i> b- :> T1 :> T1 <->*- ?- :> b- T3 -f^-a-rJ-O- ^.i. t fc 'O-?fe'O'OT3 ^b-^'TJ'CJ'O- __ __ ; D.Mg D D ( T'^ I 7^ V ^^X5 'T'^^^^N^ S i-L( ^L| i-ti H-| A t~4 (< i-U (q f< 11 ^ . MB . : 2 '. : : : : : : O-*H^ -1 ^_^ 'C5iz3 Si^' "t^A * * S S S "S "3 S"33 *3~_, a B Sji i ja-n ^-r^ ci^^^ ^'P N S-o>> o.-ooooo ooo_-CTja>S ^e^icSi:^ obE^^c ^^^rt^*-^ ccccccc i 9 S ca s * ^ ST: ^5 fc*23 'nj=^2 0^33 333J c o - - ^ ^^^= K^-g s *fl3 -H ^HvH^HiH^H ^H^H^H^H^^CNCS (NCSf*JCSCSCNC^ C^^fSfO^fOfO 1939] WINTER WHEAT VARIETIES FOR ILLINOIS 101 T3 T3 T3 T3 T3 T3 B C C C C C C . S-o-S -o-p. a s c c c CCCCBCC ccccccc ccccccc 5.S.2! 5 5 C C C C C SSlllsl II ES ES -j 3 3 33 llsllffi* ffiffillsK SS '"-S-SS 5 "PoOOuOO Jrt u o o SI O o o o u <2 rtl O o ,2 O O O X O O ,2 O X " O O O o O 0,2 X O SOOOWOO SOOWSpnO OP ^ ^2 M PH ... 00 00 C ; . . ; | o S ^(S " 2 ^ '2 OO g o T( ^. c^ ^ AH CS dS2 ::: r2!H wjS u'X .,^-r:' e <-^ S.- " ^o-sS fa rt^-ooS -c J2 .2.3 u ^ ' "" ta"S * ~ a '.',(1) '~ u ^^^rtStS SS &4J a S b 3 n o> w 2 c'3 oi W< *-'S7^(5 c v rt <" JD >> C >r">T'" N In C " lllllh ^ 2 2:s l?l 1111111 *I-S525 W aSE^I ffiK 'g582 'CC^crSw U U UOCCC wJ-Ji3^^*^^^ 00 Ov O rt (N 00 Ov O rtt 102 BULLETIN No. 460 [December, damage from scab are reduced. But the weather cannot be controlled ; and a satisfactory way of clearing up mosaic-infected soil is not known. The use of resistant varieties, therefore, is the best answer to the prob- lem of controlling wheat diseases. Resistance to each individual disease, however, is a separate prob- lem, for resistance to one disease is not necessarily associated with resistance to another. Worse than that, there are geographical influ- ences to be considered a new wheat found very resistant to leaf rust in Kansas proved susceptible in Indiana. Sometimes, as the result of chance or much work by plant breeders, resistance to two or more diseases is found in the same variety. Resistance to diseases must be combined with other desirable characters (see page 98) or the variety may still be undesirable. Furthermore, wheat must be suited to the locality. Thus we need not just one variety having all these desirable qualities, but a number of such varieties, one suited to each different geographical location. Very often the best way to determine resistance to any particular disease or diseases is to set up experimental conditions which prac- tically insure severe infection. This method is being used in studies of FIG. 4. A BAD SPOT IN A FIELD OF ILLINOIS PROGENY 2 CAUSED BY WHEAT MOSAIC This disease makes its appearance in April and is evidenced by a yellowing of plants in small or large areas in the field or over the entire field. Leaves become mottled with light-green or yellow patterns, and the plants fail to grow properly. The degree of stunting and loss of grain depends on the amount of resistance which the variety has. Definite progress is being made in the develop- ment of mosaic-resistant varieties. 1939] WINTER WHEAT VARIETIES FOR ILLINOIS 103 wheat mosaic in Illinois. Chance infection sometimes yields valuable data on relative resistance and susceptibility to a disease, but it cannot be relied upon every year. Cheyenne, for instance, gave a very good performance from the disease standpoint in the variety trials from 1932 to 1935 ; but in 1936, in tests on mosaic-infected soil, it was discovered to be very susceptible to this disease, and in 1937 it was almost ruined by stem rust over a wide area. In 1938 in the northern third of the state its yield and quality were cut very severely by scab. The resistance of the varieties included in these tests to mosaic disease, leaf rust, stem rust, and scab, so far as shown by information now available, is indicated in Table 4. Milling and Baking Qualities In rating a wheat on its milling and baking qualities many things must be considered, for these qualities vary not only with the variety but with the fertility of the soil and with the season. Ease of grinding and percentage of flour obtained are two important elements included in milling quality. Baking quality is determined by the percentage and the quality of the protein in the flour, the percentage of ash, the amount of the water absorbed by the flour when worked into a dough, and the volume, color, and texture of the baked product. With all these factors to consider, such terms as excellent, good, medium, and poor, as used in Table 4 to describe the breadmaking quality of the wheats tested, have only a very general meaning. They do, however, have this value that in so far as milling and baking qualities are to be considered by a farmer when choosing a variety to grow, those varieties described as excellent and good should always be chosen in preference to those described as medium; and those described as poor should, except for special reasons, be avoided. Recommended Soil Treatment for Wheat Of all of our field crops, wheat is one of the most responsive to treatment with fertilizers, and failures or near failures of wheat due to low soil fertility are frequent. Mineral fertilizers high in soluble phosphorus have very consistently given yield increases when drilled with wheat on run-down light-colored soils of southern Illinois. 1 On other soils having a low supply of available phosphorus the response for treatment has usually been good. 'MILLER, L. B., and BAUER, F. C. Fertilizing Illinois wheat. 111. Agr. Exp. Sta. Mimeo. Cir. Ag489. May, 1937. 104 BULLETIN No. 460 Phosphorus fertilization of winter wheat has given considerable insur- ance against winterkilling and insect injury. Potassium has seldom been effective when used alone on wheat, but it frequently gives good results when used with phosphate on soils that are definitely deficient in this element. The use of nitrogen in mixed fertilizers drilled for wheat has usually not been profitable. Nitrogen-carrying fertilizers may, however, often be used to good advantage as a top dressing in the spring, especially on the poorer soils. While taking advantage of the oppor- tunity of increasing wheat yields by the use of direct fertilization, a farmer must not lose sight of the importance and the economy of raising the general fertility level of his depleted soil by the use of good permanent- fertility practices. For wheat, as for other crops, the maintenance of a good supply of organic matter is important, and rotations should be planned with this as a goal. Recommended Practices in Growing Wheat Winter wheat usually follows spring grains or soybeans in the rotation. Sometimes it is seeded after clover or corn. When wheat is to follow spring grain and clover, the land must be plowed in prepara- tion for wheat. Summer plowing is best since it provides an adequate interval for the soil to settle before wheat-seeding time. The land may be plowed 6 inches deep if the work can be done in July, but if on account of the late removal of a crop of clover, plowing has to be done in September, the depth should be not over 4 inches. When wheat is to follow soybeans or corn, little or no work is necessary to prepare a seedbed. A double disking is the most that will be required and sometimes not this much. The date of seeding is set very accurately by the emergence of the hessian fly. Tests over a period of years show that the highest yields have usually resulted when the seed was planted on or close to the so-called "hessian-fly-free date." The following conditions and practices help to assure high yields of wheat: (1) a firm seedbed in a fertile soil or one to be fertilized at seeding time; (2) choice of an adapted high-yielding variety: (3) treatment of seed with copper carbonate or Ceresan before it is sown ; (4) drilling the seed on or soon after the fly-free date : (5) using 5 to 6 pecks of seed to the acre; (6) rolling the wheat field in the spring after the heaving freezes have past; and (7) harvesting at the proper time. 12,050-12-39-17742 UNIVERSITY OF ILLINOIS-URBANA