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Maple Dripping Sap on Car: Aphid Honeydew + Wetwood Combo

Maple Covering Car in Sticky Sap? Two Separate Issues

A maple oozing from trunk cracks (wetwood) AND dripping sticky mist on cars (aphid honeydew) has two problems. Wetwood foam comes from bark cracks; honeydew rains from canopy where aphids feed.

Issue 1: Aphid Honeydew (Sticky Car)

Control aphids with systemic soil drench (imidacloprid, dinotefuran).
Honeydew stops → sooty mold stops → car stays clean.

Issue 2: Wetwood/Slime Flux (Trunk Foam)

Bacterial fermentation in heartwood.
No cure; self-limiting.
Clean loose bark; flush with dilute bleach.
Maintain tree vigor.

Yellow Jackets and Flies

Attracted to both honeydew and wetwood sugars. Both will diminish when aphids are controlled and flux subsides.

Treat the soil for aphids; let the wetwood run its course.

Plant Diseases: Yellow Sap Oozing from an Old Red Maple: Bacterial Wetwood?; Honeydew and Sooty Mold from Aphids on Street Trees: City Management; Oak Tree Dripping Sap? It's Honeydew from Aphids or Scale; Maple Dripping Sap: Aphids or Scale and Systemic Fix; Maple Tree Dripping Sticky Sap? It's Likely Slime Flux, Not Aphids; Maple Honeydew on Property: Systemic Scale/Aphid Control; Aphid Honeydew Causing Maple Sap Nuisance; Sticky Maple Leaves: Aphid Honeydew and Pruning Timing; Maple Sap Flow After Spring Pruning: Normal and Manageable; Managing Maple Tree Sap on Driveways and Vehicles

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