Pesticides and their effects on soils and water : symposium papers sponsored by the Soil Science Society of America / program and editorial committee, M.E. Bloodworth, chairman, Texas A & M University, A.A. Hendrickson, Nodogen Laboratories, E.O. McLean, Ohio State University, C.W. Ralson, Duke University, D.M. Van Doren, Ohio Agricultural Experiment Station, C.H. Wadleigh, Agricultural Research Service, USDA ; Steven A. Breth, managing editor ; Mathias Stelly, coordinating editor, ASA special publication series.