This is the leaf of a maple tree in Cincinnati, OH. The tree is about 30...
This is the leaf of a maple tree in Cincinnati, OH. The tree is about 30 years old. As you can see, there are vertical growths on many of the leaves. I've not seen this a before and wondered if you could provide any information as to what may be causing this.
Hamilton County Ohio
This is a maple spindle-gall mite. As the factsheet below states, this is simply a cosmetic situation with the tree and very rarely needs to be controlled.
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