1. New Mexico State Univ., Dept. of Plant and Environmental Sciences, MSC 3Q, P.O. Box 30003, Las Cruces, NM 88003-8003 (corresponding author).
2. Professor, Agricultural Experiment Station Statistician, New Mexico State Univ., MSC 3501, P.O. Box 30003, Las Cruces, NM 88003-8001.
3. Professor, Dept. of Civil Engineering, New Mexico State Univ., P. O. Box 30001, Dept. 3CE, Las Cruces, NM 88003.
4. Professor, New Mexico State Univ., Dept. of Plant and Environmental Sciences, MSC 3Q, P.O. Box 30003, Las Cruces, NM 88003-8003.