1. Dep. of Plant Science Univ. of Manitoba 222 Agriculture Building, 66 Dafoe Road Winnipeg MB R2T 2N2 Canada
2. USDA‐ARS Plant Science Research Unit 1991 Upper Buford Circle St. Paul MN 55108 USA
3. Dep. of Soil Science Univ. of Manitoba 362 Ellis Building, 13 Freedman Crescent Winnipeg MB R3T 2N2 Canada
4. Northwest Research and Outreach Center 2900 University Ave Crookston MN USA