1. Water Resources Research Center; Univ. of Arizona; 350 N. Campbell Ave. Tuscon AZ 85719
2. Institute of Soil, Water and Environmental Sciences; Volcani Center; Agricultural Research Organization; P.O. Box 6 Bet Dagan 50-250 Israel
3. USDA-ARS, Agroecosystem Management Research Unit, Room 121 Keim Hall; Univ. of Nebraska Lincoln; Lincoln NE 68583
4. Univ. of South Florida; Dep. of Integrative Biology; 4202 E. Fowlers Ave SCA110 Tampa FL 33604