1. Dep. of Plants, Soils and Biometeorology; Utah State Univ.; Logan UT 84322
2. USDA-ARS; L.J. Smith Hall-Washington State Univ. Pullman WA 99164
3. Biological Systems Engineering Dep.; Washington State Univ.; Pullman WA 99164
4. Deps. of Crop and Soil Sciences and Geology; Washington State Univ.; Pullman WA 99164