1. Dep. of Plant Sciences; Univ. of Wyoming; 1000 E. University Ave. Laramie WY 82071
2. Dep. of Crop and Soil Sciences; Washington State Univ.; Puyallup Research and Extension Center; 2606 West Pioneer Puyallup WA 98371
3. Crop and Soil Science Dep.; Oregon State Univ.; Corvallis OR 97331
4. USDA-ARS, Red River Valley Agricultural Research Center; 1605 Albrecht Blvd. N. Fargo ND 58102
5. USDA-ARS, National Center for Agricultural Utilization Research; 1815 N. University St. Peoria IL 61604