Jumping Oak Gall

Oak trees develop small, round, spiky galls on leaves and twigs that look like tiny seed pods or burrs, typically appearing in late spring and summer. The galls are created by gall wasps developing inside plant tissue. The distinctive characteristic is that these galls detach from the leaf and fall to the ground where they continue developing. You notice clusters of these round, bumpy structures on oak foliage.

Gall formation involves a complex alternate-generation cycle; most oaks tolerate the cosmetic damage without serious impact. Rake and remove fallen galls from the ground in late summer to disrupt the lifecycle. Prune out heavily galled twigs during dormancy if appearance is a concern. No chemical control is warranted since galls do not cause significant plant damage.