Crapemyrtle Aphids and Sooty Mold: Diagnosis and Treatment

Charcoal-black leaves and sticky residue indicate crapemyrtle aphids. By fall, populations explode, coating surfaces with honeydew that feeds sooty mold. Winged aphids may rain down on passersby.

Control

Apply systemic insecticide containing imidacloprid in spring for season-long suppression. The black mold will weather away once aphids are gone.