Ash Tree Leaf Mystery

[Starsania]

Might someone be able to tell me what is going on with these leaves?
These bumps are on ash tree leaves. I would like to know what this would be called. Answers are much appreciated! ^_^

 

[appalachianarbo]

Ash leaf gall mite (or a close cousin to that). Cosmetic damage only. No need to worry.

The bumps are distortions caused by a chemical that the mite injects into the leaf.

You can reduce the numbers of galls by raking and destroying the leaves each fall.

 

[S Mc]

That is what I was going to say also (Aceria chrondriphora). I agree on the treatment also...rake up and destroy fallen leaves to control further infestation.

Otherwise, information I see is that it does not affect tree vitality.

Sylvia