Global Soil Partnership.
Jonathan W. Hempel, USDA-NRCS, Lincoln, NE, Kim Green, USDA-Food Safety and Inspection Service, Beltsville, MD, Dan J. Pennock, Department of Soil Science, University of Saskatchewan, Saskatoon, SK, Canada, Thomas Reinsch, USDA-NRCS, Beltsville, MD, Charles W. Rice, Department of Agronomy, Kansas State University, Manhattan, KS and David L. Lindbo, Room 4840-S, USDA-NRCS, Pittsboro, NC, US