1. Agriculture and Agri‐Food Canada P.O. Box 1030 Swift Current SK S9H3X2 Canada
2. Agriculture and Agri‐Food Canada Lethbridge Research Centre Lethbridge AB T1J4B1 Canada
3. USDA‐ARS 303 Johnson Hall Pullman WA 99164‐6434
4. Dep. Land Resources and Environmental Sci. Montana State Univ. Bozeman MT 59717