See F. R. Steiner, Soil Conservation in the United States (1990); M. Alexander, Introduction to Soil Microbiology (2d ed. 1991); E. J. Plaster, Soil Science and Management (2d ed. 1991); publications of the U.S. Soil Conservation Service.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.