Knowledgebase
Maple leaf bumps #872540
Asked June 11, 2024, 12:19 AM EDT
Hennepin County Minnesota
Expert Response
Hi Rolf,
These are maple leaf galls. There are tiny insects inside of those bumps, but they're harmless and only a cosmetic problem. The tree may lose a few leaves but the galls are no threat to you tree's health.
See more information here:
https://hort.extension.wisc.edu/articles/maple-gall-mites-eriophyidae/
Thanks!
You’re welcome!