what is wrong with my tree? - Ask Extension
Not sure the kind of tree I have, but it has had weird bumps on the leaves for several summers and it seems to be spreading.
Knowledgebase
what is wrong with my tree? #772025
Asked September 17, 2021, 9:09 AM EDT
Not sure the kind of tree I have, but it has had weird bumps on the leaves for several summers and it seems to be spreading.
Stearns County Minnesota
Expert Response
Those are called nipple galls. They are not harmful to your tree and there is nothing you can do to prevent them. Some years there are a lot and some years very few. You can make sure to completely clean up any leaves that fall. They are the tree's reaction to a tiny insect laying eggs on the leaf (think of a scab on a wound). Insect and mite galls | UMN Extension
