Field Calibration for Corn and Soybean of a Weak Organic Acid Soil Phosphorus Test Compared with the Mehlich-3, Bray-P1, and Olsen Methods.
John D. Jones, Suite 950, University of Illinois-Urbana-Champaign, Urbana, IL, US and Antonio P. Mallarino, 716 Farm House Lane, Iowa State University, Ames, IA, US