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Aphids and Sooty Mold on Corkscrew Willow: Contact vs. Systemic Control

Black aphids covering a declining corkscrew willow, with peeling black bark and sooty mold, indicate a severe infestation. Water sprays only temporarily dislodge aphids; they return rapidly.

Treatment Options

Contact spray: Orthene (acephate) applied to foliage kills on contact; repeat per label.
Systemic: Imidacloprid (Bayer Advanced Tree & Shrub) soil drench moves into leaves for longer control.
Choose based on tree size and spray equipment; soil drench is easier for large trees.

Sooty mold will disappear once aphids are controlled. Check nursery for product availability.

Plant Diseases: Willow Tree Borers: Sapsucker Holes vs. Insect Damage; Managing Aphid Honeydew on Garden Plants and Large Trees; Black Scaly Substance on Willow: Soft Scale Infestation; Giant Willow Aphids: Identification and Control; Woolly Aphids on Big Maple: Systemic Soil Drench Stops Honeydew; Willow Yellowing & Black Branches: Water + Check for Insects; Willow 25 m from House: No Subsidence Risk; Willow Flea Beetles: Annual Invasion & Systemic Prevention; Globe Willow Aphid Infestation: Sooty Mold and Systemic Control; Giant Willow Aphid Control on Large Trees

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