Some data from earlier work concerning the evolutionary correlation of anthophilous insects, entomophilous plants, herbivorous animals, and natural soil groups are briefly summarized. Presumed successive evolution of plant and animal communities from the early Paleozoic era to the more recent formation of prairies, steppes and other grassland areas is described and pictured in Fig. 6. A definite correlation has been found among the coevolution of flowering plants, pollinating insects, ruminant animals and fertility grades of natural soil groups .Plants, insects, animals (...) and soil are interrelated in evolution as reciprocal selective and regulating factors in certain biotic and abiotic environments. This complex system can be better studied by application of the coenogenic concept and hologenic and syngenic methods.Various stages of the development of an agricultural environment in the prairie areas of the North American plains are briefly described and illustrated in Plates I–VII. A new radical change in the development by the introduction of so-called “Circle Farming” is pictured in Plates VIII–IX. This new irrigated farming system is not only profitable for the increasing of yields, but promises to some extent the restoration of a biologically balanced environment in an extensively cultivated agricultural landscape. (shrink)