Harmless Leaf Galls on Black Walnut

Identification

Soft red/green growths on black walnut leaves are insect galls (likely from mites or tiny wasps). They form when the insect lays eggs and secretes growth-regulating chemicals.

No Action Needed

• Galls do not harm the tree.
• May cause early leaf drop if numerous.
• No practical control—timing would need to be at egg-laying, and damage is minor.