Control of Rose Powdery Mildew in the Greenhouse and Field. Duane L. Coyier, Horticultural Crops Research Laboratory, USDA-ARS, and Oregon State University, Corvallis. Plant Dis. 67:919. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1983. DOI: 10.1094/PD-67-919.