1. Dep. of Crop, Soil, and Environmental Sciences; Univ. of Arkansas; Fayetteville AR 72701
2. Dep. of Soil Science, Walster Rm 147, Dep. 7680, PO Box 6050; North Dakota State Univ.; Fargo ND 58108-6050
3. Melbourne Field Service Center; USDA-NRCS; Melbourne AR 72556