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Locust Trees Yellowing: Herbicide Drift or Insects?

Three 8-year-old locusts (25 ft) yellowing from south side inward over 5 days. New stems affected. Herbicide used across road—no other yard damage, no field yellowing.

Herbicide Pattern Check

Drift shows directional pattern (brown toward source, green away). "Weed & Feed" near trees kills them. If no pattern, check insects.

Insect Suspects

Honey locust plant bug: Distorted, chlorotic leaves, premature drop, second flush usual. Unpredictable yearly.
Leaf miner: Leaves look turned but partially eaten inside.
Links to UWEX and SC Forestry fact sheets provided. Photo would help.

Plant Diseases: Ash/Hickory Leaf Spot: Fungal Disease Management and Tree Identification; Locust Tree Bark Splitting and Dead Branches: Heat, Drought, and Proper Pruning; Locust Leaf Drop and Sooty Mold on Understory Plants; Locust Leaf Drop and Tiny Green Bugs: Need Clearer ID; Key Lime Leaf Drop in the Florida Keys: Water, Wind, or Fungus?; Honey Locust Leaf Drop: Root Stress from Weather Extremes; Cottonwood Leaf Drop: Aphids, Borers, or Rust?; Locust Leaf Miner: Cause of Brown, "Fired" Foliage; Goldenrain Tree Seasonal Leaf Drop: Normal Compound Leaf Shedding; Crapemyrtle Leaf Drop Caused by Pressure Washer Bleach Overspray

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