Oak Tree Honeydew Dripping: Aphids or Scale, Systemic Solution

Oak Tree Honeydew Dripping: Aphids or Scale, Systemic Solution

Mature oaks in E. Ontario dripping sticky honeydew spring to fall: aphids (curl leaves) or scale (bumps on twigs, foliage normal). Both suck sap, excrete sugar.

Control for Large Trees

• Soil-applied systemic insecticide (imidacloprid) for both.
• Fertilize: 1 lb 10-10-10 per inch trunk diameter, spread under canopy, water in.
• Repeat fertilizer late summer.
• Healthy trees resist pests better.

Why Not Spray

Canopy too high; soil drench moves up via transpiration. Address tree stress (drought) simultaneously.