1. Univ. of California Cooperative Extension Modoc County; 202 West 4th St. Alturas CA 96101
2. Dep. of Agronomy and Horticulture; Univ. of Nebraska-Lincoln; 279 Plant Sciences Hall Lincoln NE 68583-0915
3. USDA-ARS, Agroecosystem Management Research Unit, 251 Filley Hall; Univ. of Nebraska-Lincoln; Lincoln NE 68583-0937