Popular Science Monthly/Volume 76/June 1910/Scientific Work of the Department of Agriculture

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THE

POPULAR SCIENCE

MONTHLY

 

JUNE, 1910




SCIENTIFIC WORK OF THE DEPARTMENT OF AGRICULTURE
By W J McGEE, LL.D.

NATIONAL CONSERVATION COMMISSIONER (SECRETARY SECTION OF WATERS)

THE ancients saw in the four elements of earth, air, water and fire the basis of being; moderns recognize earth, air, water and sun as the prime requisites for individual and national existence.

The earth is of three parts: the life and growth on the surface; the surface, which sustains life and growth; and the part beneath, which sustains the surface with its life and growth.

The air is of four aspects: it is an extension of the earth; it yields a part of the substance for life and growth on the surface; it is a vehicle for movement of other things; and in its own movement it affects the surface and influences life and growth.

The water is of three forms, liquid, solid and gaseous, and performs five functions: it is a part of the earth; it is jointly with the air an extension of the earth; it yields the chief part of the substance for life and growth; it forms a vehicle for bodies and powers; and in its proper movement it is an effective agency of process, including life and growth.

The sun possesses several powers: it holds the earth in its place; it fixes the succession of days and seasons; it controls the forms of water and the movements of both water and air; it effectuates process, including life and growth; it yields heat, light and actinity; and it stores power on and beneath the surface in fuel to be released through fire.

The power and prosperity of men and nations are measured by knowledge of and control over these natural elements—i. e., human life is, as it were, balanced against and paired with the elementary materials and forces. In modern times the knowledge is organized in science, and both knowledge and control are gained and promoted by institutions. In leading nations these institutions are partly voluntary associations of individuals, and partly governmental agencies. During recent decades the knowledge is not merely imparted, but measurably gained by educational institutions.

In the United States the earth beneath the surface is investigated by geological surveys, state and federal; the surface is surveyed chiefly by the Geological Survey and Land Office of the Interior Department, the Soil Bureau of the Agricultural Department and the Coast and Geodetic Survey of the Department of Commerce and Labor, with corresponding instrumentalities in some states; and the life and growth on the surface are investigated chiefly by the Forest Service, the Biological Survey and the Bureau of Entomology, so far as natural conditions are concerned, and by the Bureau of Plant Industry, the Bureau of Animal Industry and the Office of Experiment Stations, so far as artificial conditions are concerned, with related instrumentalities in several states. The air in its general aspects and the water in its forms and certain functions are investigated in the Weather Bureau; as vehicles for movement of other things they are investigated in the Geological Survey and some state institutions; in their primary relation to life and growth they are investigated chiefly in the Bureau of Soils, the Office of Experiment Stations and other branches of the Department of Agriculture, and in the Eeclamation Service of the Interior Department; and in their immediate relation to life and growth they are investigated chiefly in the Forest Service, the Bureau of Plant Industry, the Bureau of Animal Industry and the Bureau of Fisheries, while the running and standing water in certain applications are considered in the Hydrographic branch of the Geological Survey, the Corps of Engineers of the War Department, the Hydrographic Office of the Navy Department and the Bureau of Corporations in the Department of Commerce and Labor. The general relations of the sun are investigated in the Naval Observatory of the Navy Department, the Coast and Geodetic Survey, the Weather Bureau and the Smithsonian Institution; the relations to the surface and its life and growth are considered in the Bureau of Soils; and the more direct relations to life and growth are considered in the Forest Service, the Bureau of Plant Industry, the Bureau of Animal Industry and other branches of the Department of Agriculture.

So far as the federal government is concerned, the four natural elements of power and prosperity are investigated or considered in themselves or in their applications chiefly in a score of bureaus in five departments, as follows:

Departments Bureaus
I. War 1. Corps of Engineers
 
II. Navy 2. Hydrographic Office
3. Naval Observatory
 
III. Interior 4. General Land Office
5. Geological Survey
6. Reclamation Service
 
IV. Agriculture 7. Weather Bureau
8. Bureau of Animal Industry
9. Bureau of Plant Industry
10. Forest Service
11. Bureau of Chemistry
12. Bureau of Soils
13. Bureau of Entomology
14. Biological Survey
15. Bureau of Statistics
16. Office of Experiment Stations
17. Office of Public Roads
 
V. Commerce and Labor 18. Bureau of Corporations
19. Census Bureau
20. Coast and Geodetic Survey
21. Bureau of Fisheries
22. Bureau of Standards
 
23. Smithsonian Institution
 

Half of the official bureaus (much more in effective strength) belong to the Department of Agriculture. This department was designed and is maintained expressly to increase and diffuse knowledge concerning the natural sources of power and prosperity; and it is significant that more than three quarters of the investigative work of the federal government has either grown up in or gone over to the youngest two departments of the federal organization, of which the last formed is essentially commercial.

The federal bureaus are supplemented by corresponding instrumentalities in most of the states, with which there is large and rapidly growing cooperation. The spirit of the work arises chiefly in, and is largely guided by, some score of voluntary associations, with an aggregate membership of several thousand, including most of the investigators for the state and federal agencies. On the whole, the state agencies are of the greater magnitude and the more largely devoted to applications, the federal agencies the more largely devoted to investigation; the latter seem to be growing the more rapidly to meet a strong demand for effective cooperation with states and associations. The most rapid growth is that of the voluntary associations, of which an increasing proportion are devoted to the application rather than to the increase of knowledge; while the growth of the investigative branches of the educational institutions is proceeding at a geometric rate.

In the strictly scientific aspect, the governmental work pertaining to knowledge and control of the natural elements enters or occupies the fields of astronomy, meteorology (including climatology), geology (including mineralogy and paleontology), biology (including phytology or botany, zoology, entomology, ornithology, ichthyology, etc.), ecology, chemistry and physics—i. e., a large part of the concrete or objective sciences; and it involves applications of all the abstract or subjective sciences, and touches on that series of human sciences with which the others are in a sense paired. In the strictly practical aspect, the work is directed specifically to the earth as affected by air and water and sun in relation to life and growth, including that of men and nations, along lines laid down in the organization of the bureaus and departments; and there is little tendency to follow the lines or occupy the fields of the conventional sciences.

The developments of the last three decades indicate an unforeseen trend: While the subjective sciences are continuing their steady advance as bases of definite knowledge, they are of lessening prominence; the objective sciences are advancing much more rapidly both as applications of the primary sciences and as branches of definite knowledge in themselves; yet the most rapid advance of all is in applications of the objective sciences (with their subjective foundation) to special lines or fields in strict accordance with the established methods and principles. So the sum of definite knowledge is subdivided into evermultiplying specialties, while the applications become essentially scientific in themselves; observation matures in experimentation, and both purposes and the objects themselves are progressively modified in ways which gradually become utilitarian, i. e., directly tributary to the power and prosperity of men and nations. Meantime the specialties rise to a new plane; in philosophic view (following the suggestions of Sir William Hamilton and Lester F. Ward) they become conative or—more abstractly—telic, and reflect that ever-springing desire for betterment expressed by invention; in practical view by the light of current progress they become directive, in that the specialist not merely investigates but gradually brings under control and redirects the natural development of the phenomena with which he deals. Now this modern trend is too definite and too consistent to escape thoughtful observers, and has indeed been widely recognized; it may justly be regarded as an expression of inherent tendency and a mark of natural if not inevitable movement. It by no means necessarily indicates a scientific decline, as some apprehend, but rather a normal readjustment of the human mind to the external factors of human existence and welfare; in fact, it but renders progressive and purposive that prevision which is properly extolled as the highest form of science. It seems to define a third stage in the advance of consciously organized knowledge: the first was the subjective stage, marked chiefly by deduction from ill-generalized and often subconscious experiences; the second was the objective or Baconian stage, marked by induction from clearly realized experiences; and the third is the directive (or panurgic) stage, marked by the combined investigation and control of phenomena. The three orders of thought are emotion, cognition, conation; the phases of faculty pass into invention, and are maturing in creation. Knowledge in the first stage was largely accidental; in the second chiefly incidental; in the third it is a means to ends. The progress was and is normal; just as objective science arose largely as applications of subjective principles, so directive science has arisen largely as applications of both subjective and objective knowledge whereby nature is rendered subservient to the power and prosperity of men and nations. The trend does not mean that science is enfeebled or degraded, but only that definite knowledge has been made common knowledge.

In the light of this trend, the rôle of the federal department is clear: Jointly with the strictly scientific associations, it is the custodian of established principles, not merely as the sum of knowledge concerning the natural elements, but as a means of control over these elements. So viewed, the entire department is in proper sense a scientific institution, and both in size and advanced position the foremost in existence. Viewed in the same light, indeed, America is par excellence a nation of science, and this all the more truly because of the general application of definite knowledge to every-day affairs. It may not be denied that the very abundance of knowledge conduces to an ease of life opposing that always rigorous and often unprofitable research required as a basis for continued progress; herein lies the chief need for a national institution of science too firmly founded on established principles to be swayed by passing opinion or popular pressure, yet too near the actualities of national welfare to drift into the realm of unreality; and here has lain the function of the department during a dozen years of wise administration.

In the department the division of the work is both logical and practical, and the methods combine investigation and direction of phenomena: they deal with the substantial basis of individual and national existence—the earth as vitalized and fecundated by the powers of air and water and sun. The primary line of work in logical order pertains to the productive surface as affected by climate and by its own life and growth; the correlative branch of the department is the Bureau of Soils. The second in order pertains to climate; its correlative is the Weather Bureau. The third pertains to the flora, native and cultivated; the correlative branches are the Forest Service and the Bureau of Plant Industry. The fourth pertains to the fauna, both wild and domesticated, correlative respectively with the Biological Survey and the Bureau of Animal Industry, together with the ancillary insect life, correlative with the Bureau of Entomology. Adjunct lines of work pertain to certain molecular relations, treated in the Bureau of Chemistry and the Office of Public Roads; to quantitative or economic relations, treated in the Bureau of Statistics; and to ecologic relations, treated largely in the Office of Experiment Stations. In each line the primary purpose is to discover facts and relations connected with development or growth; the secondary purpose is to redirect and control the course of natural development, and the ultimate purpose is to progressively artificialize the earth with its life and growth for the benefit of men and nations. In every line the constant effort is to increase the efficiency of the better and to either improve or eliminate the worse, and this in the light of all knowledge and the exercise of all natural and human power.

The immediate basis of life and growth on the earth is the soil; it yields substance for the flora, which in turn sustains the fauna. At the same time it is itself derived from cruder earth-matter largely by the action of plants and animals, and its chief elements of fertility (such as nitrates and potassates and phosphates) are organic derivatives. Thus the primary law of the soil is cumulative enrichment through interaction with floras and faunas; to this law it has normally conformed throughout the geologic ages; and the primary duty of the soil specialist is to accelerate and intensify the natural progress, and thereby to increase soil efficiency. Now the efficiency of soils depends wholly on the associated water and air (unless indeed these be considered integral parts of the soil), of which the former especially maintains a sort of circulation, dissolving earth-salts, conveying plantfood into and through the circulatory systems of the living and growing plants, and carrying the acids of growth and decay back to the earth-matter to hasten its solution—so that the active agency or principle of soil efficiency is the soil water. The normal processes are sometimes interrupted or impeded by abnormalities: Certain organic derivatives are excretory, and poisonous to the plants yielding them and sometimes to others; climatal and other natural conditions in connection with cultural changes sometimes disturb the circulation of soil water, or permit surface erosion and leaching to impoverish or even completely remove the soil; and unsuitable plants sometimes gain such foothold as to exclude organisms better adapted to normal enrichment of the soil. Accordingly, the soil work comprises (1) examination and classification of soils with respect to materials and potentialities; (2) determination of the soil water and its movements and interactions; (3) discovery of normal tendencies toward enrichment, physical, chemical and bacterial; (4) detection and elimination of abnormal tendencies; and (5) prescription of treatment required for regulating and intensifying the natural processes and thereby increasing efficiency. The researches render it clear that the soil is the product of uncounted eons of interaction between the organic and inorganic; that the slow production of a soil is a process no less definite than the quicker production of a crop or a flora; that the process may be brought wholly under human control; and that in view of increasing population, the welfare of men and nations henceforth must depend on the care and intelligence devoted to the maintenance and improvement of this gift of the ages.

The controlling condition of life and growth on the soil is climate, especially that ever-varying temperature and moisture and air movement forming weather. The first need concerning weather is foreknowledge (or prevision) definite enough to permit prediction; and while the earlier investigations were directed to this end, they necessarily included examination and classification of the atmosphere with its aqueous vapor, and determinations of temperature, rainfall, vaportension and other factors. Herein the usual course of progress was reversed; commonly discovery of principles precedes both appreciation and utilization of phenomena; but in weather work the need inspired search for the principles—i. e., the ends led the means. With like contrariety, the effort for control was directed not so much to the natural factors of weather as to the movements of men and other organisms in adjustment thereto—indeed even yet the wind bloweth as it listeth, while men merely prepare to meet or escape its force. Still, as the work progressed, both the constants and the caprices of the air with its associated water were measured in such manner as not only to permit prevision within reasonable limits, and thereby afford practically useful weather prediction, but to yield definite knowledge of a use extending far beyond the primary need. Thus, it has become clear that in so far as life and growth are concerned the role of the aqueous vapor is paramount; plants absorb and transpire water to an amount usually exceeding many times their own volume during each season; and their action affects not only the circulation of soil water air below the surface, but the humidity of the air and the circulation of both air and water about and above them. Again it appears that the average rainfall of the United States is less than half that required for full productivity in native and cultivated organisms; yet that some 90 per cent, of the rain-water gathering into streams is wasted in floods which annually wreak damage to an amount exceeding the estimated cost of flood prevention, and this despite a large saving of life and property by reason of flood warnings issued by the Weather Bureau. So the measurements are preparing the way for such control of the rain that this gift of the heavens will be made an unmixed benefit instead of a partial evil. Of the entire rainfall, only about a third flows through rivers into the sea (chiefly in floods), while it is estimated that fully half is evaporated, thereby returning to the air to affect the weather and temper the climate; and measurements of evaporation have begun, and will doubtless open means of exercising some control over the water in the air, no less than that on the surface and within the soil. Meantime it is estimated that less than a sixth of the mean annual rainfall is actually utilized in life and growth and other useful processes connected with the soil and its productions; and it is becoming clear that larger and better uses of the elemental water are possible through progressive redirection of the natural processes and powers. In the beginning, men bowed to the storm and fled the flood; later they predicted in order to seek shelter before trfe storm arrived; now they seek control at least of the storm waters in order that their volume and strength may be directed to welfare.

The four elements interact through organisms, of which the substance is mainly from the soil and water and their products; their circulatory medium and chief constituent is water, their force is from the sun, and their functions are maintained by air. During the ages the native flora adjusted itself to soil and earth-shaping agencies so closely that each type produced a surface to fit its needs—forests developing deep and friable soils and steeper slopes, grasses developing thinner soils and flatter slopes, and mosses producing spongy soils lining basins, each according to its kind and its capacity as conditioned by climate. A quarter of the area of the United States was too arid to sustain a full floral mantle, a third was wooded and more than a third was grassed when settlement began; for wherever the water supply suffices, vitality overspreads the surface and dominates the inorganic earth. Without water, vitality fails; there is neither assimilation nor germination, nor yet metabolism, in the absence of liquid, while transpiration and respiration depend largely on the passage of water from liquid to vapor. With water, the primarily organic circulation extends from the plant to the soil below and the air above and passes into still more complicated interrelations in animal bodies; and the locus of most effective energizing on the planet is the infinitely complex surface—the soil with its extensions in stem, leaf, flower, fruit and other organic bodies—at which water is continually passing from one form to another, absorbing or yielding latent heat, and mechanically interacting with the sun in seizing and storing and transferring molecular action. This is the complex in which vitality attains dominance over lower nature; and through it investigators are attaining control over the vital powers for the welfare of men and nations. Thus, the normal circulation is notably complete in woodlands, and is notably deranged by deforestation; when the trees are felled and not replaced by other cover transpiration ceases, the air dries so that seeds and seedlings may wither, and the soil-water level lowers; the duff is desiccated and wind-blown, leaving the previously porous soil to harden and bake; and as storms arise the raindrops are no longer dashed into spray by twigs and foliage and conveyed gently through litter and natural mulch into a friable soil of enormous capacity for feeding springs and brooks, but beat still harder the indurated ground—and then gather in surface rivulets and rills running swiftly down the slopes, eroding and gullying the soil on the way, clogging valleys with the debris, and rushing as turbid torrents into the sea with little benefit and large injury on their way. The Forest Service was created largely to counteract reckless deforestation and maintain the timber supply in certain sections of the country; yet it has grown into administration of 170,000,000 acres of woodland, while its highest duty has come to be that of acquiring and diffusing definite knowledge and directing specific effort toward control over the powers of nature in such manner as to protect the water supply and regulate that balance of industries connected with woods and waters required for the common prosperity. The investigations extend into vegetal physiology and the vital mechanism of the individual seed or slip or tree no less than into the collective action and relations of the forest considered as a unit, and pass over into both natural and artificial production. The aim is increased efficiency of both individual trees and forests; the end is higher national efficiency; the means, progressive control over natural powers through definite knowledge and purposive application.

Over millions of acres of grass-lands and former woodlands, the native flora is wholly or partly replaced by crop plants, and it is the manifest destiny of all available lands to be consecrated wholly to production or inhabitation or other human uses. In prehistoric times men began to subsist on the products of the soil, and through unwitting selection improved wheat and rye and barley and rice in the old world and corn and beans in the new; and during the historical period the improvement of the useful types and the replacement of Useless or noxious types were continued under the guidance of increasing knowledge. Since the Department of Agriculture was created—and largely through its agency—the sum of human knowledge relating to crop plants and their efficiency in this country has more than doubled; and now the utility of plants is traced directly to individual vitality—to the specific factors of cell function and reaction to stimuli and hereditary tendency combining with capacity for transpiration to determine rate and limit of growth—which is itself measurably susceptible of modification. In this way the Bureau of Plant Industry is steadily gaining control over the powers of nature through redirection of the vital energy of the plants along more useful lines directed toward ends of human welfare. The control is collective no less than individual: Native plants vary, and the fitter survive; Darwin noted the increasing variation of plants under domestication, and thereby detected a natural law of increasing plasticity of types; and now under the law variability is accelerated and the fitter forms are selected and multiplied, so that the efficiency of crops is increased. Under natural conditions, plants spread slowly and with the tediousness of unlimited time adjusted themselves to particular soils and climates; with settlement, pioneers introduced new plants which were often found fitter than those of native growth; now the plains and mountains of the world are scoured to find types adapted to less productive districts, and thereby the efficiency of entire floras is increasing. And the end is not yet. Agriculture began with the accidental dropping of seeds in accidentally fertilized spots; in time the middens were expanded into gardens and these into fields; and now plain common sense and reasonable foresight look to the extension of planting and cultivating and cropping over all the humid country and so far into the arid lands as complete utilization of the scant waters will permit. Our 3,000,000 square miles or 2,000,000,000 acres, now sustain about 90,000,000 inhabitants, or 30 per square mile, and our exports of food-stuffs are falling off; within 65 years the population will doubtless double, and by the end of the century it will treble—yet the 250,000,000 mouths must not only be fully fed, but a margin of food-stuffs for export must be left over if prosperity is to persist. To attain this end, plant efficiency must be increased; not only must two heads of wheat be made to grow where a blade of grass grew before, but each square rod must be made to yield a bushel instead of a peck of grain, and more nutritious grains must be invented and created and kept employed in converting the crude ore of lower nature into the coin of individual and national welfare. It is no longer enough to know the plants and vital processes of nature; it is becoming necessary so to redirect nature as to produce more efficient plants by improving the vital processes—and this is a current duty of the Bureau of Plant Industry.

Even more plastic than plants are the faunal forms, both wild and domesticated; and before history began, kine and swine and sheep and fowls were so far artificialized by selection and breeding that the ancestral forms were obscured. It is the business of the Biological Survey and Bureau of Entomology to investigate the native fauna and classify the forms, technically into orders and genera and species and practically into useful and injurious—and then to perpetuate the good and reform or extirpate the evil, operating largely through the vital forces of the organisms themselves; and the world is scoured for information as to species and stocks of mammals and birds and fishes, for insect mates to symbiotic plants and insect enemies to noxious organisms, and even for germs and cultures affecting the course of organic progress. Meantime the Bureau of Animal Industry is not only acquiring and diffusing definite knowledge concerning stocks and breeding and feeding, but is importing and acclimating and crossing the animals with the view of supplying each section with forms adapted to its particular conditions and requirements. Thereby the domesticated animals are modified and adjusted to a complex industrial mechanism, each yielding flesh or milk or leather or textile or eggs or feathers or labor after its kind in connection with the human purpose; and if the natural powers are feeble or aimless, they are so redirected and intensified as to increase the efficiency of the organisms in promoting the welfare of men and nations.

Broadly, the functions of the other Federal Departments pertain chiefly to relations among men, those of the Department of Agriculture chiefly to the relations between men and nature. Its primary purpose, both logical and legal, is to increase and diffuse knowledge concerning those fundamentals of human power and prosperity residing in the soil and its products. In carrying out this purpose, it necessarily assimilates and promotes that consciously organized and definite knowledge pertaining to nature which constitutes both the subject-matter and the object-matter of science; and with its growth it has been called on to make all manner of applications, from the extirpation of insect pests to the protection of the purity of foods and medicines for men and the making of roads for moving the produce of the soil. Its final function, which has arisen and taken form with its growth, is the redirection of natural processes and powers along lines which are not only prevised, but clearly preconceived in relation to ends—and hence are practical. In performing this function, it deals constantly with the four primal elements in their relation to man; beginning with the earth, it progressively increases the efficiency of soils and plants and animals; and through this element it utilizes and so gains partial control over the air, the water and the power of the sun—and the measure of the. efficiency is human power and prosperity.

Thus far the relations chiefly considered in the Department of Agriculture have been those of nature, and of men to nature, adapted to increasing the efficiency of nature for human ends; there has been little effort to apply the natural powers to men or to increase their efficiency except by arming them with better knowledge. The time for directly increasing human efficiency by intensifying human power has hardly come; yet it may easily be descried as the next stage in the development of relations between men and nature.