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Locust Tree Honeydew on Vehicles: Aphid/Scale Control

Source of the Sticky Mess

The "sap" coating your car is honeydew from aphids or soft scales feeding on the locust. These insects suck phloem sap and excrete sugar-rich waste that drips onto everything below.

Effective Treatment for Large Trees

Spraying a 35-year-old locust is impractical. Instead:

Apply Bayer Advanced Tree & Shrub Insect Control (imidacloprid) as a soil drench around the dripline.
Roots absorb and translocate insecticide to canopy—kills feeding insects systemically.
Treatment lasts full season; takes 1–2 weeks to reach top of large trees.

Product: Bayer Advanced Insect Control

Vehicle Protection in the Meantime

Park as far from tree as possible.
Wash weekly—honeydew itself doesn't damage modern clear coats if removed promptly.
Removal tips: Yellow NZ Guide | US Auto Parts Guide

Key Point

Control the insects, and the honeydew stops. Soil-applied systemic is the only practical solution for large trees.

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