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UNIVERSITY OF ILLINOIS, 
 
 Agricultural Experiment Station. 
 
 CHAMPAIGN, AUGUST, 1889. 
 
 BULLETIN NO. 6. 
 
 A BACTERIAL DISEASE OF CORN. 
 
 INTRODUCTORY. 
 
 Maize, or Indian corn, is the most important crop throughout a very 
 large portion of the United States, and so any injury whatever to the plant 
 is a matter of serious concern. In the whole range of the vegetable king- 
 dom there are few plants that can compare with it in normal vigor and 
 abundant general productiveness. No other agricultural crop so domi- 
 nates the appearance of the fields throughout the great corn belt in our 
 country, and none returns to the pockets of the producers so large a total 
 sum of cash. "Corn is king," and apparently must remain so in the 
 political economy of our part of the world. 
 
 To those who have made themselves acquainted with the prevalent 
 diseases and injuries of other vegetable productions and who reflect upon 
 the vast areas annually planted to corn, often successively during many 
 years on the same land, it must be a matter of supreme satisfaction that 
 this magnificient staple so far, to an exceptionable degree, escapes the 
 harmful attacks of vegetable and animal parasites and the destructive rav- 
 ages of larger insect and other animals. Still, because of the immense 
 amount of the cereal produced, the total annual losses from such causes 
 make a vast financial showing. The entomologists count insect pests 
 injurious to corn by the score, some of which are charged with enormous 
 aggregate destruction. No one has more carefully studied or more fully 
 made known these insect depredators than Professor S. A. Forbes, State 
 Entomologist of Illinois, as his published reports show. In a lecture on 
 " Insects Affecting Corn," delivered by him before many farmers' institutes 
 in Illinois, during the last half-dozen years, he has brought together and 
 
1 66 BULLETIN NO. 6. [August, 
 
 presented in a popular manner the existing information upon the subject, 
 with enlarged illustrations of several species and representations of their 
 work. 
 
 Besides the destruction by insects, there is known to be considerable 
 loss from fungous parasites. Among these the best known is "smut," 
 the great sooty masses that form on any part of the plant above ground, 
 but very commonly on the ear, which the fungus more or less displaces 
 by its own unsightly production. This smut is a vegetable parasite. It 
 sends its delicate fibres much too fine to be seen with the unaided eye 
 through and through the tissues of the stalk, beginning when the latter is 
 is very young, and finally forms its abundant mass of black spores in the 
 swollen projections so well recognized by every one. These sooty spores 
 are the germs for the next year's smut, enough of them lasting over winter 
 to perpetuate the fungus. There is also a rust upon the leaves of corn 
 quite similar to that known by the same name on wheat, but compara- 
 tively much less destructive. This, too, is a fungus, growing in the tissues 
 and living upon the juices of the corn plant. A few others of somewhat 
 like character are known to injure the crop, especially during certain sea- 
 sons unusually favorable to their development. 
 
 But we are to write of quite another thing. We hear much nowadays 
 of "disease germs." It has been positively ascertained, and is now gen- 
 erally accepted as an incontrovertible fact, that the communicable dis- 
 eases of animals (including man), that is, those which are transmissible 
 from diseased to healthy individuals, are dus to living organisms. These 
 gain entrance in some way to the body, rapidly multiply in number, take 
 their nourishment from the normal stores of the animal, and usually cause 
 therein injurious chemical changes. By far the largest number of these 
 disease agents belongs to the group of exceedingly minute plants called 
 bacteria a word with which all are now familiar, though those who have 
 not had the opportunity of seeing them under a compound microscope of 
 high power may not have a very definite idea of the organisms themselves. 
 An individual among them consists of a single cell, which owing to its 
 exceedingly minute size can not be very well studied as to its further 
 structure. It is, however, known to consist of an outer membrane or 
 wall with contents of a different character. There are no organs or mem- 
 bers of any kind, save that some varieties have issuing from one or both 
 ends of the miniature body a hair-like projection capable of rapid vibra- 
 tory motion by which the little individual swims in the liquid in which it 
 is immersed. Food can be taken only in the liquid state, by absorption 
 through the exterior wall. Multiplication takes place by a single 
 cell becoming transversely divided and the two parts enlarging so as to 
 form two cells, each of which is exactly like the original one. In all cases 
 the two young cells may at once separate, but in the case of certain spe- 
 cies they commonly remain attached so as to form a necklace-like string, 
 or, with certain others, in little squares with the individuals in rows both 
 ways. Some kinds produce "spores." The contents of a cell collect in 
 
1889] A BACTERIAL DISEASE OF CORN. 167 
 
 a definite manner in the middle or at one end of the cavity, become con- 
 siderably condensed, and form about themselves a special wall of their 
 own. Subsequently the wall of the original cell decays or becomes 
 dissolved, freeing the internally formed spore. These spores, owing to 
 their greater density and consequent stronger refraction of light, have a 
 glistening appearance under the microscope. They are able to withstand 
 injurious substances and degrees of temperature far beyond that of the 
 vegetating cells in which they are produced. Under proper conditions 
 they may germinate, each forming again a cell like that in which it was 
 formed. This is the simple story of their life. There is no sexual or 
 other differentiation among the individuals. Any one may become two 
 by dividing, as described; and, as this process can take place under 
 favorable circumstances in a very short time and be constantly repeated 
 in similar manner, the number of individuals increases in geometrical 
 ratio and soon becomes enormously great. It is on this account that the 
 little things, insignificant as individuals, become irresistible agents of de- 
 struction. When disease is "caught" from one previously infected, it is 
 due to the transfer of some of these living atoms capable of originating 
 a myriad progeny in the previously healthy body. 
 
 Compared with the number of communicable diseases due to bacteria 
 affecting animals, there are few known in the vegetable world, though some 
 have been as definitely and conclusively established. Among the latter 
 may be counted the so-called fire blight of apple and pear trees; a disease 
 of hyacinth bulbs; and, without attempting to exhaust the list, a disease 
 of broom- corn and sorghum, *the latter being very similar in character- 
 istics and comparative amount of injury to that to be here described of 
 Indian corn. 
 
 APPEARANCE IN THE FIELD. 
 
 The first indication of the disease in a field of corn as noticed in 
 ordinary observation, is the dwarfed condition of the young plants. This 
 commonly occurs in spots of various sizes from a few square rods to an acre 
 or more, and often, though by no means always, on soil of character some- 
 what different from the rest of the field. It seems hard to designate what 
 special condition or quality of soil is most usually associated with the 
 disease; but, upon the whole, it is found in the rich spots rather than in 
 those of poorer quality. In many cases it is upon the lowest ground, 
 whether or not water has temporarily stood in the hollows. The most 
 defin'Uely bounded area noticed was upon a spot which had until the year 
 previous been too wet for tillage but which had been tile drained and broken 
 up, the sod having rotted. This was planted the following spring with the 
 rest of the field and no part seemed to be in better condition for a heavy 
 
 * Kurrill : Proceedings American Society of Microscopists, 1887. 
 
 " Proceedings Society for the Promotion of Agricultural Science, 1887. 
 " Report Board of Trustees, University of Illinois, 1887-88. 
 Kellerman and Swingle : First Annual Report, Kansas Experiment Station, i88. 
 
: 5 BULLETIN xo. 6. [August, 
 
 crop. The season (iSS~) was quite dry, and there was at no time subse- 
 quent to the planting any superfluous water in the area described. The 
 seed germinated and the young corn grew satisfactorily until after the 
 second plowing when the plants were more than six inches high. Then 
 the newly tilled spot showed, by the change in the appearance of the corn, 
 in a very definite manner, to the very furrow on the margins, a distinct 
 difference from the rest of the field. The corn ceased growing, became 
 yellow and unusually slender, then for the most part died. Careful exam- 
 inations showed that the trouble was not due to insects, but to the im- 
 mediate agency of the bacteria described below. The destruction was so 
 complete that the spot was replanted, and, singularly enough, this time 
 grew to large size though more or less diseased- A few stalks of the first 
 planting after a time seemed to recover from the malady and for a long 
 time showed high above the younger growth. But ordinarily there are no 
 such definite borders to the infected areas, and often nothing whatever to 
 suggest a reason for their peculiar distribution. It may be stated here 
 that later in the season, after the tassels have appeared, the disease may 
 be found widely scattered throughout the field, affecting only here and 
 there a stalk or hill, while the rest remains free from it. 
 
 Upon closer observation it is found that young diseased plants, 
 besides being smaller than the healthy ones, are uniformly yellowish in 
 color, the lowest leaves showing worst As death overtakes these leaves, 
 they apparently succumb by a general decline from the healthy state, and 
 rarely die and wither chiefly at the ends and margins as in some other 
 cases. When some of the affected plants are pulled from the ground, 
 they are found to give way too easily in consequence of the death, to a 
 greater or less extent, of the oldest and lowest roots. In anything like 
 severe cases at least one-half the roots always the lowest are injured 
 and usually dead. The bottom portion of the stalk is likewise affected 
 and will be found dead or dying. If split longitudinally through the 
 middle, the inner tissue of this lower part is seen to have a uniform dark 
 color; and a similar discoloration, gradually becoming less and less pro- 
 nounced, appears in the next succeeding nodes or joints, while the spaces 
 between them (internodes) are seemingly healthy. On the surface when 
 carefully freed from dirt, brownish, corroded spots can be found, some- 
 times strictly bordered, again diffusely spreading. Sometimes masses of 
 semi-transparent, rather firm, gelatinous material are found upon these 
 external corrosions. 
 
 After midsummer, especially, the disease becomes apparent through 
 discolorations of the portions of the leaves called the sheaths, which 
 closely invest the stalk. These leaf-sheaths become variously spotted as 
 observed from the exterior. Sometimes the watery-brown portions are 
 mere specks: sometimes large irregular patches, and of all grades between 
 these extremes. The discolorations become brown, of a half-rotten appear- 
 ance. Occasionally there is a little reddish color, more often bordering 
 the brown. If now these affected leaves are stripped from the stalk, it 
 
1889] A BACTERIAL DISEASE OF CORN. 169 
 
 will be found that the evidence of injury is much more conspicuous on 
 their inner side. The injured patches are larger, have a more watery 
 appearance and sometimes are more or less smeared with the same gelat- 
 inous substance previously mentioned as occurring on the diseased stem 
 below ground; but here on the leaf-sheaths it is usually spread in a thin- 
 ner coating or layer, instead of in rounded masses. This infection of the 
 leaf-sheaths evidently comes later in the season than the first noticed 
 form of the disease on the roots. It seems also to be evenly distributed 
 through the field and to occur upon large as well as small plants. 
 
 Finally, the ears are, at least occasionally, affected. Externally, the 
 appearance of the outer husks is like that of the diseased leaf-sheaths. 
 Internally, in the worst stage, the whole ear husks, which should be still 
 green, young cob and kernels, and the mass of " silks " is reduced to a 
 moist state of corruption, though not ill-scented. The parts lose their 
 normal rigid or turgid quality, appear as if wilted, and are packed closely 
 together, if not actually adhering by the gummy exudation from the 
 tissues. Very often these ears subsequently become mouldy, penetrated 
 through and through by a close, very white, felt-like fungus. Possibiy 
 this fungus sometimes makes its inroads into the ear without the bacteria 
 as forerunners: but from present knowledge it seems probable that it is a 
 secondary intruder. These mouldy ears are in certain seasons very 
 numerous and are readily recognized by the busker, as well as by the 
 buyer when the loads are sent to market. 
 
 HISTORY OF INVESTIGATION*. 
 
 During the year 1882, Professor S. A. Forbes, while studying the work 
 of chinch bugs on corn, sent me for examination portions of corn stalks 
 and leaves, collected in McLean county, upon which were found the cor- 
 roded spots above described, and, associated with these, the gelatinous 
 substance above referred to. During this same time the chinch bugs 
 were found to be infested with bacteria, which soon swept them all off by 
 a veritable contagion. Since the bacteria- possessed insects were found 
 on the corn and these lumps of jelly also full of bacteria along with them 
 on the corroded leaf-sheaths (the injury was then supposed to be solely 
 the work of the insects), notwithstanding tne different appearance of the 
 organisms under the microscope, the jelly was referred to in the published 
 description of the chinch bug parasite* as zooglara masses. ' The state- 
 ment was, however, shown to be doubtful by the insertion of an interro- 
 gation mark. 
 
 This is believed to be the first published reference slight as this is 
 to the cotn parasite with which we now deal. 
 
 At various times many examinations were made upon the roots of 
 sickly corn in which there was no evidence of insect work, with the ex- 
 pectation of finding, if anything, the mycelium of a fungus. These once 
 
 American Naturalist. 1883. p. 319. 
 
170 BULLETIN NO. 6. [August, 
 
 and again proved abortive, and the conclusion was finally reached that no 
 such parasitic growth existed in connection with the malady. 
 
 The next critical investigation of growing corn affected with the dis- 
 ease came about in a very similar manner. During several years preced- 
 ing 1889, the chinch bugs were exceedingly numerous and destructive, 
 especially throughout the southern portion of Illinois, and the state entomol- 
 ogist was earnestly endeavoring to collect all possible information concern- 
 ing them and the peculiarities of their life history. At Albion, Edwards 
 county, 111., a field of corn belonging to J. Skeavington was found which 
 presented so poor an appearance, without evidence of insect depredations, 
 that in July, 1887, Professor Forbes brought home some of the plants for 
 further study. Some of these were turned over to me for examination. 
 The descriptions already given of the affected roots and leaf-sheaths 
 might have been written from these stalks; and, furthermore, the organ- 
 ism was identified to which we now attribute the malady. Search was 
 now made in fields near the University and the disease was found in 
 progress. Studies were carried on during some weeks, the specific organ- 
 ism being invariably found associated with the affected parts; pure 
 cultures were secured and inoculations made in healthy corn. The latter 
 failed. On this account no publication was made of the facts obtained, 
 it being thought desirable to ascertain positively the causative action of 
 the bacteria before proceeding further. During the season of 1888, 
 other things demanding first attention, no further studies were made upon 
 the disease except to note its occurrence and distribution. A field of 
 forty acres near Kankakee, Illinois, was found almost ruined by this dis- 
 ease. In this case the land was excellent in quality and in good condition, 
 and the corn had been well cultivated. The seed had come up well, and 
 for a time the growth progressed finely; but nearly all the stalks remained 
 abnormally small; many gave no indications of earing and the best of 
 them produced "nubbins" rather than ears. It was found here, as in 
 some previous cases, that after the lowest roots had died and others had 
 been put forth above the former, these later roots soon became diseased. 
 Sometimes when the "brace" roots issuing from the stem above ground 
 reached and penetrated the soil, they, too, became corroded, or sloughed 
 off in a mass of brown mucilage, thus in effect destroying the plant. The 
 characteristic bacteria were found present. 
 
 The next thing which drew renewed attention to the matter was the 
 discovery by Dr. F. S. Billings,* of the Agricultural Experiment Station 
 of the University of Nebraska, an acute observer and thorough-going 
 pathologist, of a "germ " in cattle which had died after feeding upon corn 
 stalks in the field, at Ames, Nebraska, January 6, 1888. Other cases 
 occurred at different places in the state and received more or fess atten- 
 tion until, finally, in the winter and spring of 1889, the distinguished 
 investigator took up the subject for more special research. Having 
 
 * Original Investigations of Cattle Diseases in Nebraska, 1886-88, Bulletin of Experiment Station of 
 Nebraska. 
 
1889] A BACTERIAL DISEASE OF CORN. 171 
 
 learned of my examinations of corn diseased in the fields, he asked me 
 for a description which he included (page 199) in the volume referred to. 
 He also sent cultures of the organisms obtained by him from infected 
 animals for comparison with those taken by me from the growing corn. 
 They seemed to be alike. In March I applied the Billings "germ" from 
 a culture to some young corn which we happened to have growing in the 
 greenhouse. Nothing came of this, though inoculations and smearings 
 were made in several ways. Rabbits and mice, however, quickly suc- 
 cumbed upon inoculation. Some wild gray rabbits, which had been 
 proof against the hog cholera "germ," died within six days after sub- 
 cutaneous inoculation. 
 
 Finally Professor Forbes found, near Sycamore, Illinois, July, 1889, 
 indications of this newly studied disease throughout considerable areas. 
 He again brought in specimens and examination proved his suspicion 
 correct. Soon afterward the writer visited the fields mentioned and many 
 others through the northern part of the state. Of the places visited the 
 disease seemed to be worst in the Sycamore region; but more or less evi- 
 dence of it was found in numerous widely separated localities. At Syca- 
 more some improvement had apparently taken place since the first named 
 observation, the later roots appearing free from injury. But in certain 
 fields a large percentage of the stalks showed no indications of earing and 
 could not, it was thought, after that time (August ist), produce anything 
 like a satisfactory crop. 
 
 After receiving the first diseased plants from Sycamore, search was 
 again made at Champaign, and the malady was found in several fields. 
 Cultures and inoculations upon growing corn were made, and this time 
 with unmistakable results. The bacteria, in pure cultures, were applied to 
 the inner surface of the leaf-sheaths, without puncture, and the watery- 
 brown spots appeared in four days while the organisms multiplied enor- 
 mously in numbers and were taken still pure in favorable cases in 
 considerable quantity from the affected surfaces. 
 
 Time has not permitted a large number of these experiments, and the 
 results so far obtained do not warrant a conclusion as to the reason of 
 previous failures in the greenhouse and out of it; neither have we, so far, 
 satisfactory results from application to the roots and subterranean stems. 
 But with the positive results from inoculation of the leaf-sheaths and the 
 abundant evidence upon examination and culture, it cannot be doubted 
 that the specific bacteria are the direct agents in the destructive work. 
 
 This is written August i6th. During the last ten days inoculation 
 and feeding experiments upon a small scale have been tried upon rabbits 
 without positive results. These tests are too few and too recent to be of 
 much import 'here; but they do serve to show that the "germ," if the 
 same as that in the experiments of Dr. Billings, has not now the virulence 
 that his had either with him or myself. The identity of the two is there- 
 fore still to be proved. 
 
172 BULLETIN NO. 6. \_AugUSt, 
 
 THE BACTERIA. 
 
 As has been indicated above, the disease organisms in this case are 
 found in great numbers on and within the affected parts of the roots, the 
 subterranean stem, the leaf, and the ear. In many cases they collect on 
 these surfaces in gelatinous lumps or masses which really consist, for the 
 most part, of the organisms themselves held together by the stiff muci- 
 laginous substance which they themselves exude. If. a microscopical 
 preparation is made directly from this jelly, it will be found that the indi- 
 vidual organisms are quite variable in shape, though many of them are 
 elongated, almost cylindrical, with somewhat tapering ends. The 
 usual stains affect these little rods in a peculiar manner. One, or more, 
 often two, dot-like portions take a deep color while the rest remains 
 unstained. When these dots are near the middle, as is more often the 
 case, the extremities usually become less and less visible, until it is only 
 possible to make out the terminal portions with a good objective and 
 excellent illumination. But mixed with these elongated forms are many 
 of quite uniformly oval shape, very often joined two and two by their 
 contiguous ends. These stain solid throughout, or are paler in a central 
 transverse band. All variations occur from a very narrow pale central 
 band up to a very wide one, and in the latter case only the tips of the ovals 
 are colored by the dye. These peculiarities of staining are almost 
 exclusively confined to the fresh substance as collected from the plants. 
 When the bacteria have been grown in artificial cultures, they usually 
 stain uniformly solid throughout, though occasionally pale-centered indi- 
 vidvals are found. Upon first examination, any observer would at least 
 suspect that the oval and elongated forms described were different spe- 
 cies; but cultivation tests show that both belong to one and the same 
 thing, and in all artificial media tried they are always quite or nearly oval 
 in shape, though often differing considerably in size after the culture 
 becomes more than eighteen to twenty hours old. 
 
 They divide in one plane only, in the direction of the short axis. It 
 is very common, especially when they are rapidly growing, to find them 
 in couples; but they rarely adhere in strings of greater numbers. They 
 multiply rapidly at the ordinary temperature of the laboratory, but seem 
 to grow fastest at about 36 C. (97 F.). It should be said, however, 
 that, though the recent work was done in midsummer, the room in the 
 basement of a large building and on the north side was always cool 
 enough for comfort. 
 
 In notes made upon the organisms in 1887, they were said to have 
 swimming movements in fluids; but in the examinations made in 1889, such 
 movements have not been detected, though trials were made from fresh 
 liquid and solid cultures, in beef broth and in water, at the ordinary temper- 
 ature of the room and warmed upon the stage to 36 or 37 C. However, 
 these trials were only made a few days before this writing and may not 
 indicate the full truth. This peculiarity of movement differs greatly 
 according to conditions, though certain species never possess it. 
 
1889] A BACTERIAL DISEASE OF CORN. 173 
 
 Nutrient gelatine is not liquified. In a " stab " culture in this medium 
 there is to be seen along the needle tract after twenty-four hours, a gray- 
 ish streak, which becomes slightly diffused by minute lateral ramifications 
 into the substance, the borders not being very definitely marked. But 
 the spreading does not, with more time, long continue; hence the line 
 does not become more than an eighth of an inch wide. On the surface 
 the growth spreads in a definitely bordered circle, commonly somewhat 
 wavy, and is lusterless. On the sloping surface of an agar tube the growth 
 is prompt and characteristic, forming during twenty to thirty hours at 
 36 C. an opaque, lusterless, white streak with margins nearly even or reg- 
 ular. On examination with a lens, it can be made out that the mass is 
 not entirely homogenous. There are obscure rays of more or less opaque 
 character, sometimes giving a slightly feathered, often a simply mottled, 
 appearance. If the medium is quite moist, the pasty mass at length runs 
 down and collects at the bottom of the tube. The growth never becomes 
 diffused in a film over the surface. In liquids the tube becomes uniformly 
 turbid within twenty-four hours, plainly more so in the incubator at the 
 temperature named. At the end of this time, though not much before, 
 there appears on the surface a thin, fragile pellicle which readily breaks 
 up on handling and slowly settles to the bottom. No spores are formed. 
 
 In fresh cultures of beef broth the ovals average a little longer than 
 they do when grown on solid media. On quite moist agar, the two diam- 
 eters of the individuals in a culture eighteen hours old differ but slightly 
 and the shape is very uniform. The transverse measure, however, in all 
 fresh cultures is very nearly uniform and is about .65 micron (.00026 in.). 
 The most common length of a newly divided pair is 1.6 micra; each 
 individual being about .8 micron.* Single ones average a little longer and 
 occasionally reach the length given for a pair. 
 
 *A micron is one-thousanth of a millimeter, or about one twenty-five-thousanth of an inch. 
 
174 
 
 BULLETIN NO. 6. 
 
 FIGURE SHOWING FORMS OF THE BACTERIA, MULTIPLIED 3,333 TIMES. 
 
 * 
 
 /N ii '- 
 
 Desciiplion of Figure. The figure is a photo engraving from a drawing by A. M. 
 Wesiergren, under a Tolles' ^g-inch homogenous immersion objective, with aHughenian 
 eye piece furnished with a Rogers micrometer. The instrument magnified, as used, 1,650 
 times (diameters). Lines were drawn on the paper corresponding to those of the mi- 
 crometer, so as to mate the magnification exactly 5,000 times. Reduction of one-tlvrd 
 was made in the engraving, so that the representation, as it now appears, is 3,333 times 
 the natural size. In making the drawing there were used three slides from cultures each 
 of which was known to be pure, and one slide made directly from the gelatinous 
 substance on a leaf-sheath. The endeavor was made to select from these four slides all 
 forms and sizes of the organisms which they contained and thus to show, as nearly as 
 possible, all the variations of the species. Every individual figured was drawn as accu- 
 rately as possible from the actual object. Methyl-violet stain was used. 
 
 The typical form is represented by those of medium size having an oval shape, 
 most numerously shown. The largest ones are indicated by the two near the center of 
 the figure, and the peculiar appearance of those not becoming uniformly stained is shown 
 near the top. The two, near together, with dark color near the ends only and a much 
 paler but somewhat colored central area, are types of those obtained from mounts made 
 directly from the diseased plants. The seemingly perfectly spherical forms are supposed 
 to he standing on end, though there is some doubt in regard to the largest of these. The 
 greatly elongated forms with central dots are not shown in the figure. 
 
 REMEDIAL TREATMENT. 
 
 We know too little of the disease to be able to suggest a remedy. In 
 the studies made during the last two weeks especially, there appears to be 
 in a considerable number of cases more injury on land which has been 
 planted with corn the preceding year, though the rule does not always 
 hold good. In one case the worst results followed when timothy sod had 
 
1879] A RACTER1AL DISEASE OF CORN. 175 
 
 been broken up and corn planted thereon; while a timothy pasture not far 
 distant, treated in the same manner gave a thoroughly healthy crop of 
 corn. Grass and weeds have been 'carefully examined without finding 
 indications that the same disease affects them. Probably the bacteria 
 live over winter in the soil, though we have no experimental data for this 
 opinion. If this is a fact, then young corn would be liable to suffer when 
 growing upon land on which the preceeding crop was diseased. When it 
 is definitely known whether anything besides corn is affected, we shall be 
 better able at least to theorize upon a cure. 
 
 From observations now made it appears that the disease is a very 
 prevalent one and, probably, has existed during the time that corn has 
 been grown on the continent. If so, it has not ordinarily attracted atten- 
 tion and, very likely, is not destructive enough to be specially noticed. 
 When, however, under peculiar circumstances, the crop is injured to the 
 extent now sometimes known, the loss is very great, not only to individual 
 farmers, but to the country at large. 
 
 THOMAS J. BURRILL, Ph. D., 
 
 Horticulturist and Botanist. 
 
 All communications intended for the Station should be addressed, 
 not to any person, but to the 
 
 AGRICULTURAL EXPERIMENT STATION, CHAMPAIGN, ILLINOIS. 
 
 The bulletins of the Experiment Station will be sent free of all 
 charges to persons engaged in farming who may request that they be sent. 
 
 SELIM H. PEABODY, 
 
 President Board of Direction. 
 
BULLETIN NO. 6. [August, 1889. 
 
 ORGANIZATION. 
 
 BOARD OF TRUSTEES OF THE UNIVERSITY OF ILLINOIS. 
 
 ALEXANDER McLEAN, Macomb, President. 
 
 JOSEPH W. FIFER. Governor of Illinois. 
 GEORGE S. HASKELL, Rockford, President State Board of Agriculture. 
 
 RICHARD EDWARDS, Superintendent of Public Instruction, 
 
 S. M. MILLARD, Highland Park. GEORGE R. SHAWHAN, Urbana. 
 
 CHARLES BENNETT, Mattoon. W. W. CLEMENS, Marion. 
 
 OLIVER A. HARKER, Carbondale. FRANCIS M. McKAY, Chicago, 
 
 EMORY COBB, Kankakee. SAMUEL A. BULLARD, Springfield. 
 
 BOARD OF DIRECTION OF THE EXPERIMENT STATION. 
 
 SELIM H. PEABODY, LL. D., Champaign, Regent of the University, President. 
 
 E. E. CHESTER, Champaign, of State Board of Agriculture. 
 
 HENRY M. DUNLAP, Savoy, of State Horticultural Society. 
 
 H. B. CURLER, DeKalb, of State Dairymen's Association. 
 
 EMORY COBB, Kankakee, Trustee of the University. 
 
 CHARLES BENNETT, Mattoon, Trustee of the University. 
 
 GEORGE S. HASKELL, Rockford, Trustee of the University. ' 
 
 GEORGE E. MORROW, A. M, Champaign, Professor of Agriculture. 
 
 THOMAS J. BURR1LL, Ph. D., Urbana, Professor of Botany and Horticulture. 
 
 THE STATION STAFF. 
 
 GEORGE E. MORROW, A. M., Agriculturist. 
 THOMAS J. BURRILL, Ph. D., Horticulturist and Botanist. 
 
 DONALD McINTOSH, D. V. S., Veterinarian. 
 
 THOMAS F. HUNT, B. S., Assistant Agriculturist. 
 
 GEORGE W. McCLUER, B. S., Assistant Horticulturist. 
 
 ALBERT G. MANNS, Ph. D., Assistant Chemist. 
 
 B. S., Assistant Chemist. 
 
 WILLIAM L. PILLSBURY, A. M., Champaign, Secretary. 
 
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