Honey Locust Sudden Defoliation: Water Stress or Root Rot

Year-old honey locust leafed well, then yellowed and dropped leaves in showers after 5 weeks. Drip + sprinkler irrigation; basalt rock mulch. Other trees fine.

Diagnosis

Tree is stressed, shedding leaves to conserve energy. Two main possibilities:

1. Overwatering/root rot: Saturated soil kills roots.
2. Environmental adjustment: Leaf drop compensates for site change.

Action Plan

• Reduce watering: let root ball dry significantly, then deep soak.
• No fertilizer except organic (compost, dry molasses).
• Check root flare: should be visible at base. If trunk goes straight in like a post, excavate soil to expose flare—buried flare impairs water/nutrient uptake.