Q: Can you tell me what this is on my maple tree? It seems to be on much of the lower foliage. Your advice on this strange phenomenon will be appreciated.

A: You have maple eyespot gall. Although it looks like a fungal disease, it’s actually caused by a midge (a small fly-like insect). The female lays eggs in the undersurface of the leaves. The maggot that hatches develops quickly and produces a hormone that causes the bright red and yellow rings around the original egg damage.

Despite its distinctive appearance, eyespot gall does not harm the tree. It’s just another natural phenomenon to file in the back recesses of your brain.

Maple eyespot gall

Maple eyespot gall

Maple eyespot gall