“History is largely a record of human struggle to wrest the land from nature, because man relies for sustenance on the products of the soil. So direct, is the relationship between soil erosion, the productivity of the land, and the prosperity of people, that the history of mankind, to a considerable degree at least, may be interpreted in terms of the soil and what has happened to it as the result of human use.”

Hugh H. Bennett and W.C. Lowdermilk