Assessment of Foliage Diseases of Alfalfa in Wyoming. F. A. Gray, Associate Professor, Plant Science Division, University of Wyoming, Laramie 82071. Plant Dis. 67:1156-1158. Accepted for publication 5 July 1983. Copyright 1983 American Phytopathological Society. DOI: 10.1094/PD-67-1156.

Disease nurseries of standard cultivars were used to assess foliage diseases of alfalfa. One nursery was placed in each of six (five irrigated and one dryland) geographically diverse growing areas in Wyoming and monitored over a 3-yr period. Common leaf spot, downy mildew, spring black stem, and yellow leaf blotch were detected. The first three diseases occurred at all irrigated sites except Laramie, where common leaf spot was not found. Yellow leaf blotch occurred at a measurable level only at the dryland site and appears to be the major disease of dryland alfalfa in Wyoming. Diseases detected in nurseries were the same as those found in surrounding commercial fields.