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not for scientific or practical purposes, but breadth of knowledge along many lines of botgave source to wild speculations in disease and any and one marvels at the enormous amount the origin of life. However, its useful day of research work he did. Nor should we omit came many years later, when its discoveries to mention the great work of Tulasne (who were made use of in many practical problems, had the merit of first breaking the ground in connected with disease of plants and animals a study of rust, smuts and ergot), on the disand the physiological problems in connection covery of the germination of the spores of with crop production.

rusts, smuts and the sexual organs of Perono

spora. While these researches did much for PLANT PATHOLOGY

mycology, indirectly they have been of great Meyer, an extraordinary man who died at practical importance to pathology. Robert the age of thirty-six, published a work on Hartig, perhaps the foremost student in the phytopathology, a paper on corn smut and one world during his lifetime of the diseases of on actinomyces. He was a physiologist and forest trees and the decomposition of wood, looked at the problem of disease from the exerted a great influence on the practise of standpoint of physiology, really the only way forestry, followed later by the splendid work the subject should be treated. Camerarius of Marshall Ward, a student of Hartig. We seems to have antedated the work of Meyer by may mention in this connection the work of over one hundred years in the publication of Fischer de Waldheim, Wolff, Sorauer, Appel, his paper “De Ustilagine Frumenti.” Julius Millardet, Prillieux, Jones, Halsted, Arthur, Kuehn was primarily an agriculturist and as Bolley, Atkinson, Stewart, Whetzel, Freeman, director of the Agricultural Institute at Halle Clinton, Thaxter, Duggar, Stakman, Cook, started a series of experiments on plante that

Stevens and Melhus. These as well as have become classic. While thus engaged in

host of others, added to this economic phase the work he became interested in a study of of botany, making secure the science of the diseases of plants. To him we owe the first plant pathology. I need only add here comprehensive treatise on plant pathology that the stimulus given by these men to He had breadth of vision to study and inter- this economic phase of botany has been compret what he saw with the microscope and thus municated to all parts of the world; and there came into being “ Die Krankheiten der we may mention especially the pioneer Kulturgewächse," which stands as a monu- work by Dr. Farlow on Gymnosporangium, ment to his labors. It is the only botanical grape vine mildew, onion smut, Dr. Burrill paper by him listed by Pritzel in his The

on apple blight and sorghum blight, the epochsaurus. M. J. Berkley's work, “ Introduction making researches along the line of bacterial to Cryptogamic Botany,” gave to English- diseases of plants by Dr. Erwin F. Smith. speaking people the first real treatise on plant Surely America may well be proud of its diseases, which laid a sure foundation for a achievements. The present age has hundreds study of plants, along economic lines.

of new problems in plant pathology. The All of the work on plant diseases and the superficial only was touched on by the early anatomy of plants was better established later workers. We may mention especially the root through the classic work of DeBary. De- disease of cereals and other crops. The plant Bary, of course, did not have, except in some pathological studies on these parasites has cases, the practical problems in mind, though changed our methods of agriculture comthe science of botany and plant pathology in pletely. We need more careful and profound particular have been greatly benefited through work on many of the problems worked upon his profound researches in connection with by the pioneers. The pioneers who blazed the the development of life history of fungi. De- way may be excused for errors, but the modo Bary brought to the science of mycology ern investigator should not be. He has the

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equipment and money and should do good in practical problems. Earlier Sir Andrew work.

Knight had demonstrated “that no plant ferPOLLINATION OF FLOWERS

tilizes itself through an unlimited number of Another phase of the subject of economic generations.” Dr. Gray put this in a much botany is that of pollination. Progress was more terse way. A score of investigators like slow. Geoffroy, who as early as 1711 made

Hermann Mueller, Fritz Mueller, Delpino, some observations on the nature of the style, Ludwig Axell, Hilderbrandt and in our counis said to have conducted some experiments

try men like Gray, Trelease, Riley, Foerste, with maize; however that may be he did make

Beal and Robertson demonstrated the use of use of the work of Camerarius. Geoffroy con

insects in pollination and the application of cluded from various sources that fertilization

this fact to important agricultural crops. These was a kind of fermentation, but he was in

fundamental facts are fully recognized to-day clined to accept a second view of Morland that in the growing of apples, alfalfa, sweet clover, the pollen grains contain the embryo which melons, squash and cucumbers. The orchardfind their way to the seed. We may also recall

ist recognizes the importance of bees in conthe work of John Logan, at one time gove

nection with the growing of apples, pears and ernor of the colony of Pennsylvania, who plums. The farmer recognizes the importance conducted experiments on the fertilization of

of bees in the alfalfa and sweet clover fields, maize, in which he noted that cobs covered just as Charles Darwin recognizes that the with muslin did not produce seed, but seed bumble bee is important in the red clover polwas formed on cobs where pollen came in con

lination. In this connection, as an economic tact with the stigmas. Logan suggested that problem, I may call attention to the honey the wind carried the pollen. Gleditsch in a

flow in flowers. It is true beekeeping is only study of one of the palms (Chamærops

one of our minor agricultural problems dehumulis) strewed loose dried pollen on the

pendent entirely on the relative abundance of stigmas of a female plant which produced seed

honey plants in a given region. There are a which later was planted and germinated; a

great many interesting physiological problems simple experiment but a convincing one to the in connection with nectar secretion, as Kenoyer botanists of the time, who had never seen pol

has shown. One wonders why alsike clover lination demonstrated before. Philip Miller scarcely yields any nectar for bees in Iowa in 1751 calls attention for the first time to the and yet in some regions of the country it is importance of insects in the pollination of

one of the best of nectar plants. There is tulips. The first scientific experiments on hy

seldom any nectar in buckwheat flowers after brids were made by Koelreuter, who discovered

10:00 A.M. in Iowa, and yet in sections of the the use of nectar and the importance of in

United States the period of nectar flow is

much longer. Is soil alone a factor or is sects in the pollination of flowers. Koelreuter

moisture an important factor, or are the two clearly set forth the facts that the mingling

factors combined ? We have enormous exof two substances produced a seed. These

panses of waste land along our highways in general statements as set forth by him still

the United States, why not combine the eshold true. He was a skillful experimenter in

thetic with the economic if we can find plants the hybridizing of plants. The work of

that are suited for such places that will yield Sprengel on the pollination of flowers is well

good returns for the beekeeper. known to the older botanists. His sharp discriminating observations on the relation of

PLANT BREEDING insects to flowers were little understood at the I heard a practical fruit grower in Iowa say time. The full import of these problems were the other day when a new chance seedling recognized by Charles Darwin, who in his apple was shown me that nearly all of the new masterly way showed the application of this good things in the fruit line are chances; that is to say the new productions by Burbank, We have a truly modern work by one whom Hansen, Patten, Beach, Hedrick, Webber and we may regard as a modern man of science. many other plant breeders are not equal to He made a comparative study, correctly deterthose found in nature. I need only recall mined the relation of the endosperm to the the many fine things the modern plant breeder cotyledon and named the embryo. We have has produced. Of course, new types will al- had a long line of investigators on the subject ways appear, as they have in the past. The of seeds. work accomplished, it seems to me, will The practical application found expression justify larger expenditure of money.

in the work of Nobbe, Harz and others. We In the matter of fundamental study of may recall the work of Nobbe in the testing these problems practical agriculture, horticul- of seeds at the small experiment station at ture and floriculture are indebted to the Tharand, which was the beginning of the exclassic fundamental work of Hoffmeister and periment stations such as we know them toStrasburger. This work led up to and ex- day. Nobbe did not merely do the mechanical plains the physical basis of Mendelism dis- part in connection with the testing of seed, covered by Gregor Mendel, a work that is but inquired into real scientific problems in most important in the breeding of new types. connection with specific gravity, and the vitalWe have had a host of botanical investigators ity of seeds under different conditions of who have enhanced our knowledge of plant storing. The germination of many seeds is breeding, linking it with practical work like of special concern to the agriculturist, beNilsson, Johannsen, Bateson, Correns, Shull, cause it is important to know under what White, Webber and Emerson. Agriculture conditions a seed will germinate best to bring and horticulture are indebted to the epoch- the largest returns. It is a matter also of making work of DeVries on mutation. His some concern for the farmer to know whether work has set a score of botanists to work on weeds' seeds have a varying period of vitality the pedigree culture work. I may mention when buried in the soil, whether for instance Nilsson, Johannsen and Gates especially. Pos- the seeds of Hibiscus Trionum and Abutilon sibly the outstanding problem of the pomolo- Theophrasti will come up in his fields after a gist in states like Iowa and Minnesota is that quarter or half a century when he practises of hardiness. In breeding experiments at the rotation of crops. The vitality and structure present time it is necessary to set the trees of seeds has of course received much attenout and test them for a term of years, to see tion. I need only recall the classic work of whether or not this climate is too severe. DeCandolle who more than a century ago Bakke in some recent experiments has found studied the prolonged vitality of seeds. The that by ascertaining the depression of the data secured by DeCandolle is frequently freezing and the moisture content at a time quoted in text-books of plant physiology. when all the tissues are in an active state of Also much later work of Becquerel, Beal, growth, it is possible to obtain an idea of the Ewart and Hanlein on delayed germination, comparative hardiness of different apple trees. as well as the work of Crocker and his stuThese tests have been made upon trees in the dents like Shull, on the delayed germination of nursery as well as upon trees in an orchard, seeds, like wild oats and other seeds of eco10 years old, with practically the same results. nomic importance. To Crocker we are in

debted for an explanation of the delayed SEED STUDIES

germination of such seeds as the cocklebur. After a consideration of pollination the Knowing that there is a delay in some seed matter of seed is of importance. The first the farmer is better able to follow a rational great work published is that of Gartner, "De practise in the treatment of seeds. I am sure fructibus Seminibus plantarum.” Gartner was that most of you are familiar with the work free from the bias of those who preceded him. of Schleiden and Vogel, Chalon, Malpighi,

GRASSES

Haberlandt, Sempolwski, Beck, Moeller and seeds is concerned, has not been entirely Oesterle, Mattirolo and Buscalioni, Hanausek, solved and awaits solution by the investigator. Harz, Junowicz and many others who were The writer and Miss King, during the past interested in a study of seeds of Leguminose, few years, have continued investigations on particularly with reference to the light line. germination of seeds of forest trees and The writer more than a quarter of a century shrubs. The results exhibit surprising irregago brought the literature on this subject to- ularity and uncertainty in the germination of gether in his paper on the Comparative these seeds. Boerker, of Nebraska, has folAnatomy of Seeds of Leguminose.” Com- lowed the same line of research. The work of paratively little has been done since. In- Sir John Lubbock on Seeds and Seedlings tensive studies on the seeds of such families and various papers of Tubeuf on seeds of as the Leguminosæ. Convolvulaceae, Cucurbi- forest trees, although purely morphological taceæ, Malvaceæ, Tiliaceæ should be made be are always valuable for reference and bear in cause in most of these families where the general upon forestry problems, of economic light line occurs the seeds have a prolonged botany. vitality. The subject has more or less of a practical bearing. The problem as to the Botanists have long recognized the imnature of the light line in these seeds has not

portance of grasses in our welfare. The been solved. A number of present-day botan- prosperity of the United States outside of the ists, like Martin, Harrington and others are rich natural resources of forestry, mines and taking up the problem. Present-day investi- water power is concerned with the economic gations with seeds are bringing many valuable production of cereals, cotton and livestock. practical results in commercial seed produc- Turning to some of the older works I recall tion, as in clovers. The seed control work by the work of Sowerby and Parnell on grasses, the establishing standards of purity is a prac

Metzgar, "Die Gereidarten, Stebler and tical problem. The work in determining the

Schroeter, "Körnicke, Die Gebreidearten," and conditions of germination, experiments with

Hackel, “ True Grasses.” In our own counlight, electricity, heat, moisture and drying

try early works were Flint's “ Grasses of and studies of seed coat are also important.

Massachusetts," Klippart, “Grasses of TenThe important problem of rate of maturing

nessee,” Lapham, “ Grasses of Wisconsin," of seed in storage is being worked out. Seed

Vasey, “ Grasses of the United States," Lamtesting laboratories, while they are obliged to

son-Scribner, various papers published by the answer the immediate pressing problems on

U. S. Department of Agriculture, Beal, the impurities of seeds and their germination

“Grasses of North America," Hitchcock and

Chase papers. These and other authors touchare engaged in a study of the more funda

ing the economic problems of cereals, like mental problems of the viability of seeds. It

Hunt, Carleton, Shear, Warburton and Ball has been the custom for the American Seed

have stimulated prduction but it would seem Analysts Association to send to its co-workers

as though we have only scratched the surface seeds to test for purity and vitality. With

so far as a study of the real problem of cereal careful treatment, there is still the greatest production is concerned. It vitally concerns variation in the results. Presumably, in part

us as a nation to stimulate the production of at least, the methods used by seed testers is

cereals and forage crops because the ever-innot the same and, therefore, the result can

creasing population demands increased pronot be uniform. We should bear in mind

duction. How can the botanists contribute that the viability is a natter of climate and

more to the welfare of mankind than to study condition of storage of the seed. The funda

such problems as the physiology of the nutrimental problems of every one of the great tion of the growing of wheat, maize, oats, barstaple agricultural crops, so far as vitality of ley and rice, or to make a study of pollination

seasons

no

are

on

under different climatic conditions, or the law would be obeyed and the weeds would soon breeding of varieties of cereals resistant to be eliminated, but instead they are constantly diseases? We might well consider the stu- increasing. As illustrations of weed legislapendous losses from parasitic fungi of cereals. tion I need only remind you that some twentyThere never was a time when research on five years ago nearly all the northwestern cereals and other agricultural crops was as states made it illegal to permit Russian thistle important as it is to-day. We have, on a to grow. During these twenty-five years it large scale, undertaken the removal of the has spread from the Atlantic to the Pacific. barberry in the wheat-growing section of the In Washington and Colorado where the condicountry, because the plant pathologists are tions are suitable it covers the ground on convinced that the common barberry is an im- little travelled roads and on the plains. In portant factor in rust production. And yet, Iowa we made an effort by legislation to reI was confronted with the frequent statement duce the infested areas of quack grass, but by practical men in western Minnesota that it has so increased that the farm values in there is no barberry in this particular section. some cases are reduced because of its presence. I certainly saw none in the immediate area During the past two seasons I have received to speak of, although there was some bar- a large number of specimens of knapweed berry thirty miles to the south. I could (Centaurea solstitialis) from many points in not make the questioner see the importance Iowa and northern Missouri, distributed of the barberry in connection with grain largely through alfalfa seed. Buckhorn (Planrust. Some

doubt there tago lanceolata) is rapidly interfering with actually viable uredo spores grasses. clover culture in Iowa. The point, I think, we should determine We have described weeds and how to to convince the wheat grower on is this: eradicate them, because this is the kind of inare the uredo spores viable in weedy grasses, formation the farmer wants, but we have not and how far the uredo spores be solved a single one of the important problems carried? The farmer who loses $3,000 on a in connection with weeds. Weeds have an imquarter section of land in a single year of portant bearing on the crops produced. The wheat-growing wants some solution of the small ragweed no doubt reduces the efficiency problem. It is the duty of the government of the Iowa pasture during the autumn and the botanist to solve the problem for the months fully one half, the weeds of corn fields country. Unless this is done by extermina- frequently cut the yield one third. How these ting the barberry, the breeding of resistant yields are reduced has not been determined. varieties and the elimination of weedy grasses, How much do we know about the mechanical the growing of spring hard wheats will be a interference of weed roots and the agriculthing of the past, and the farmer will be tural crop? So far as I know, there is abforced to turn his attention to the growing of solutely no data on the subject. Water is other cereals, not subject to rust. The gov- an important factor in crop production; thereernment and the states directly interested, can fore, a study of transpiration is of importance well afford to spend a half million dollars an- in connection with a study of weeds. It has nually until the problem is solved.

been pointed out by Livingston that transpiration is practically a simple function of

the leaf surface and that the total transpiraThe subject of weeds is related to that of tion is a measure of the growth of a plant, plant disease. It greatly interests the farmer whether it is one growing in a waste place or and gardener. The farmers of the United

of economic importance. States, at least in some sections, have en- Kesselback makes it clear that weeds such as deavored to remove by legislation some of the sunflower use more than three times as much injurious weeds, expecting, of course, that the water per plant as corn. while water used per

can

WEEDS

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