Sycamore Sudden Defoliation: Not Anthracnose, Check Trunk Wounds

Sycamore Sudden Defoliation: Not Anthracnose, Check Trunk Wounds

Large sycamore (50 ft, 23+ years) rapidly losing leaves in summer with white powdery material on leaf veins (normal), no trunk cracks: defoliation cause unknown but not anthracnose (which causes brown blotches).

Investigation

• Re-examine trunk thoroughly for hidden wounds, borer holes, or girdling roots.
• Check for herbicide exposure (weed-and-feed nearby).
• Assess root zone for construction damage or compaction.

Care

• Deep water weekly.
• Fertilize with slow-release tree fertilizer.
• Monitor for re-leafing (sycamores often push second flush).

Sudden summer defoliation in sycamores often traces to vascular disruption from trunk/root injury.