1. New England Plant, Soil, and Water Laboratory; USDA-ARS; Orono ME 04469 USA
2. USDA-Natural Resource Conservation Service; Washington DC 20250 USA
3. Friedman School of Nutrition Science and Policy; Tufts University; Boston MA 02111 USA
4. Eastern Regional Research Center; USDA-ARS; Wyndmoor PA 19038 USA
5. Southern Regional Research Center; USDA-ARS; New Orleans LA 70124 USA