Treatment for possible anthracnose on our maple tree - Ask Extension
We live in White Lake Michigan and have a maple tree roughly 7 years old. Suddenly this spring, it has black areas (not raised) on the leaves. It's al...
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Treatment for possible anthracnose on our maple tree #933539
Asked May 30, 2026, 1:00 PM EDT
We live in White Lake Michigan and have a maple tree roughly 7 years old. Suddenly this spring, it has black areas (not raised) on the leaves. It's also producing seeds. I suspect it's Anthracnose. Assuming so, is there any treatment we should give it this year as well as early next spring to prevent future breakout. Thank you.
Oakland County Michigan
Expert Response
Hello
Anthracnose on established maples is cosmetic and needs no treatment. If treatment were warranted it is too late this year to do so. Preventative fungicides applied in early spring every 2 weeks can reduce anthracnose on maples.
You can keep fallen leaves raked up now, through the season( if any) and in fall to reduce chances of anthracnose. If the tree is very densely branched, correctly thinning the canopy to promote air circulation can be helpful. Keeping the leaves dry by redirecting lawn sprinklers, or by watering early in the morning so leaves dry quickly in the sun, is helpful, too.
Here are pictures to compare with what you see on your leaves. https://www.canr.msu.edu/news/maple_leaf_blister_and_anthracnose_two_foliar_diseases_that_can_appear_on_s
Anthracnose on established maples is cosmetic and needs no treatment. If treatment were warranted it is too late this year to do so. Preventative fungicides applied in early spring every 2 weeks can reduce anthracnose on maples.
You can keep fallen leaves raked up now, through the season( if any) and in fall to reduce chances of anthracnose. If the tree is very densely branched, correctly thinning the canopy to promote air circulation can be helpful. Keeping the leaves dry by redirecting lawn sprinklers, or by watering early in the morning so leaves dry quickly in the sun, is helpful, too.
Here are pictures to compare with what you see on your leaves. https://www.canr.msu.edu/news/maple_leaf_blister_and_anthracnose_two_foliar_diseases_that_can_appear_on_s
