Image of Disholcaspis plumbella

Description:

Gall formed by a cynipid wasp on the west coast. Can be greenish with yellow spots or lumps, or wine red with yellow spots or lumps. There is a curved pointed beak opposite the end of attachment. Occurs on blue, scrub, live, and leather oaks in late spring and early summer. Often remains on the oaks for several years. Wasps emerge November and December. - Ron Russo Field Guide to Plant Galls