Steven B Mirsky, Sustainable Agricultural Systems Lab, USDA-ARS, Beltsville, MD, Hanna Poffenbarger, Plant and Soil Sciences, University of Kentucky, Lexington, KY, US, Brian Davis, Maryland, University of Maryland, College Park, MD, Michel A. Cavigelli, Bldg 001 Rm 140, USDA-ARS, Beltsville, MD, John T. Spargo, Tower Road, Ag Analytical Services Lab, University Park, PA, Brian A. Needelman, 1213 HJ Patterson Hall, University of Maryland, College Park, MD, US, Jude E Maul, Bldg. 001 rm. 123, USDA-ARS, Beltsville, MD and Stephanie A. Yarwood, Environmental Science and Technology, University of Maryland, Bowie, MD