What is wrong with this Oak tree?

Asked June 14, 2020, 5:14 PM EDT

I believe this is a Burr Oak. Can you please tell me if this is Oak Blister or something else? Taken in Cumberland, WI Thank you.

Barron County Wisconsin

1 Response

These are leaf galls, formed when an insect feeds on the leaf. They are harmless on healthy mature trees. Read here: