I have 2 10+ year old Autumn Blaze Maole trees that are generally heathy but...
I have 2 10+ year old Autumn Blaze Maole trees that are generally heathy but this year there are these red dots/bumps on many of the leaves. The bumps are bright red and some of the leaves are so covered in them they are curling up. The bumps are almost exclusively on the front side of the leave. The leaves otherwise seem healthy - they a re not turning brown but with excess curling up. The problem seems to be worse on the lower branches. I can't check the top of the tree to confirm there are none but it looks normal toward the top and I don't see the curling leaves. My guess would be some kind of bug eggs but I've never seen this before and don't see it listed anywhere. What is it? Will it harm the tree? Will it spread? Do I need to or can I 'treat' it?
Hennepin County Minnesota
Maple bladder gall ,Vasates quadripedes, are the plants response to a mite. Nothing can be done once they are formed.