1. USDA‐ARS, Plant Sciences Res. Unit and U.S. Dairy Forage Res. Center Cluster, and Dep. of Agronomy and Plant GeneticsUniv. of Minnesota411 Borlaug HallSt. PaulMN55108
2. Dep. of Agronomy and Soils201 Funchess Hall, Auburn Univ.AuburnAL36849
3. USDA‐ARS‐NPSBldg. 005 BARC‐WestBeltsvilleMD20705