Oak leaf gall / egg cases id

Asked July 15, 2015, 12:01 PM EDT

Hello! Mature oak tree spotted w/ tan-colored lumps on the leaves. Texture is like that of hardened foam sealant, approximately the size of a pea. Each leaf had from 1-3 galls ((or egg cases?). Also spotted were small fuzzy, reddish bumps - couldn't tell if they were insects or fungi or others. Each approximately the size of 1/2 a pea, and also from 1 - 3 per leaf. Tree roots are partially compromised- half of them in compacted soil, the other half in unused park space. All nodules seem to be located on the lower branches, approximately 6' from the ground. Couldn't see many nodules higher than that, but I also couldn't really see the top side of the leaves higher than 6'. This tree is located on Hoover Road NE, between Lawrence and Monroe Streets NE.

District of Columbia County District of Columbia

1 Response

Based on your photo this looks like a gall on the leaf most likely produced by a wasp. There are many types of leaf galls. Chemicals produced by the egg laying and feeding activities cause most insect and mite galls. The chemicals cause the affected plant cells to swell. No control is necessary. See our website for photos and more information https://extension.umd.edu/hgic/shade-tree-galls
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