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Sooty Mold and Honeydew on Oak in South Africa

Cause

Black sticky coating on leaves, walls, and car is sooty mold growing on honeydew excreted by aphids or scale insects.

Control

Apply Bayer Advanced Tree & Shrub Insect Control as a soil drench. Roots translocate imidacloprid to foliage, killing sucking insects. Takes 2+ weeks to reach canopy. Product link: Bayer Advanced.

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