Howard D. Ohr is Extension Plant Pathologist, University of California, Riverside. M. K. Murphy is Staff Research Associate, Cooperative Extension, University of California, Riverside. Emmylou M. Krausman is Staff Research Associate, Department of Plant Pathology, University of California, Riverside. Robert M. Endo is Professor of Plant Pathology and Plant Pathologist, University of California, Riverside. J. Michael Henry is Farm Ad visor, Orange County.