Hickory petiole gall
Phylloxera caryaecaulis

• Round galls, up to 1" across, found on leaf petioles and occasionally on leaflet midribs
• Galls begin to appear in early May and are fully-formed by mid-May
• Numerous galls may deform leaves
• Leaves fall prematurely late in summer and canopies appear thin
• More information on Hickory petiole gall...