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Mystery Leaflet Drop on Honey Locust: Seeking On-Site Diagnosis

20-ft 'Skyline' honey locust drops healthy leaflets (no chew marks, no discoloration) from SW side (2/3 lost). No herbicide/insecticide used. No insects seen. Root collar healthy. No extreme weather. Water not an issue.

Assessment

This pattern (one-sided, healthy leaflets falling) is unusual for diseases or insects. Suggests:

Root zone moisture imbalance (e.g., SW side drier/wetter).
Girdling root on one side.
Vascular issue localized to one side.

Next Steps

Contact county agricultural extension for a site visit.
Consult local nursery/arborist with photos and history.
Monitor for progression—if spreads to other sides, urgency increases.

On-site evaluation is essential for this puzzling symptom.

Plant Diseases: Honeylocust Dropping “Seeds” and Thinning: Insect Frass, Not Seeds; Locust Trees Yellowing: Herbicide Drift or Insects?; Honey Locust Transplant Failure in Heat: Emergency Recovery Protocol; Locust Leaf Drop and Sooty Mold on Understory Plants; Locust Leaf Drop and Tiny Green Bugs: Need Clearer ID; Honey Locust Without Seed Pods: No Cause for Alarm; Honey Locust Sudden Defoliation: Water Stress or Root Rot; Honey Locust Thorn Injury: Likely Retained Splinter or Infection; Honey Locust (Gleditsia triacanthos); Honey Locust Identification: Thorny but Wildlife-Friendly

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