Alder with Black Sticky Coating: Aphids and Sooty Mold

Systemic soil drench: Imidacloprid (Bayer Advanced) – best for large trees.
Foliar sprays: Acephate, bifenthrin, malathion, oils – need full coverage.

Black "Burned" Look = Sooty Mold on Honeydew

Aphids suck sap, excrete honeydew. Sooty mold grows on it, blackening bark and leaves. Dripping sap is honeydew.

Ants often tend aphids. Controlling aphids eliminates mold and ants.

Trees: Saving a Sick Apple Seedling: Powdery Mildew Diagnosis and Treatment; Woolly Aphids on Big Maple: Systemic Soil Drench Stops Honeydew; Globe Willow Aphid Infestation: Sooty Mold and Systemic Control; Aphid Honeydew on Beech Tree: Identification and Control; Sticky Maple Sap on Cars: Aphid Honeydew Solution; Hackberry Dripping Sticky Residue: Aphids and Sooty Mold; Why Your Mature Jade Plant Is Losing Branches: Natural Self-Pruning vs. Root Rot; Diagnosing Leaf Drop in a Mature Rubber Tree; Ficus benjamina Dropping Leaves: Light, Water, Pot Size; Woolly Alder Aphids on Elm: Honeydew, Sooty Mold, and Control Options

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