Soil Classification and Cartography in Relationship to Other Soil Research

OOIL research has become increasingly specialized ^ and sectionized as it has developed, despite the obvious interrelationships among the several parts. This is partly because the technics of many other sciences, more or less modified, are used in soil science. Some make particular use of the technics and materials of geology, others of chemistry, of physics, or of biology. Many researches in soils are so technical that a high degree of specialization, for a large number of workers at least, seems essential; although the need of some acquaintance with several sciences, as a necessary prerequisite to the study of the fundamental principles of soil science, is being appreciated more and more. To a considerable degree, these principles are developed through the integration of the principles and laws of other sciences; but not through simple addition, any more than the properties of water can be learned by adding those of pure hydrogen and pure oxygen. These two elements must be studied together. One cannot come to a useful understanding of the course of water through a soil, of the genesis of a soil profile, or of the probable production of hay that will follow the planting of alfalfa seed on a certain soil, from the single approach of chemistry, of geology, of physics, or of biology. Specialization may also arise from a wholly different course — from the nature of the problems being investigated. Like all applied sciences, applied soil science is shaped to a considerable extent by the nature of the problems pressing for solution. Let us take soil physics as an example. There may be studies from the point of view of problems in highway construction, of the erosion problem, of the problem of soil structure maintenance, of problems in land drainage, and so on. Although each investigator, if he digs at all beneath the surface, ultimately finds himself concerned with the same fundamental properties of soils, each may develop more or less individual technics, and accumulate particular kinds of data, according to the original approach. Naturally, this process cannot go on very far or there would be hundreds of kinds of specialists, one group for each important problem, with no end of confusion and duplication. Gradually we have recognized that certain types of research give results applicable to a great many problems. The great emphasis given to studies of soil chemistry in relation to problems of soil fertility in western Europe, as compared to the emphasis given to studies of soil morphology and geography in Russia, no doubt reflects differences in the nature of the problem to be solved — in the one case an increasing population on soil naturally unproductive for crop plants, and in the other the organization and colonization of a great continental empire. Thus, specialization in soil science has arisen because of variations in scientific training and approach, and because of differences in the problems to be solved. That there is some confusion of purpose, of methods, of concepts and of nomenclature in presentday soil science, can scarcely be denied. If one consults a modern book dealing with general chemistry or geology, one knows about what to expect. But a look into a new book on general soil science promises to be a new adventure. Yet what is amazing, to me at least, is not the present confusion, but rather, considering the newness of the science, the complexity of the problems, and the wide variety of approaches, the progress toward common principles that has been made.