Maple Tree with black spots on leaves

Asked September 20, 2018, 3:35 PM EDT

I have a maple tree that is now 15 years old. The past four years in late summer early fall the leaves develop black spots. Is it dangerous to the tree? Do I need to treat it and if so with what?
Thank you for your time.
Kimberly Groce

Washtenaw County Michigan

1 Response

What you are seeing on your maple leaves is a fungal disease called Tar Spot. Tar spot on maple leaves is a cosmetic problem and a yearly occurrence in Michigan.

To avoid infection next year, MSUE recommends you rake up and destroy the fallen leaves this summer to prevent overwintering of the fungal spores. Even then, if your neighbor's trees have Tar Spot, the spores can be carried by the wind onto your maple leaves next year. The good news is that this disease causes no harm to your tree and requires no action on your part other than raking and destroying fallen leaves as mentioned above.