

Begin by raking up and destroying all fallen leaves. Infection that begins early in the season can be devastating and may warrant the use of fungicides.Ĭultural controls should be the first line of defense. Prevention & Treatment: Most powdery mildews of landscape trees occur late in the summer and are therefore of little consequence. Warm, dry days and cool, damp nights favor disease development. Powdery mildew is most common in dense, shady areas where the air circulation is poor. Spores are spread by wind to surrounding dogwood plants. Infected leaves exhibit marginal leaf scorch, dead patches, reddish discoloration, yellowing, and premature defoliation. New growth is covered with a fine, white, powdery coating, typically on the upper leaf surface. Powdery Mildew: Erysiphe pulchra (formerly Microsphaera pulchra) is the fungus that attacks leaf surfaces and tender shoots and causes powdery mildew. James Blake, ©2007 HGIC, Clemson Extension Powdery mildew on dogwood (C ornus florida) leaves.
