Sugar Maple Leaf Black Spots

Thank you for writing.
That looks like anthracnose.
https://extension.umn.edu/plant-diseases/anthracnose-trees-and-shrubs
https://www.umass.edu/agriculture-food-environment/landscape/fact-sheets/maple-anthracnose
Please have an arborist (see my signature line) see this tree soon.

Steve Miles, Master Gardener, Hennepin County, (I am a volunteer human being: not a bot, not AI). I'm an avid gardener but not a degreed or certified horticulturist or arborist. I will do much better if you also send a photograph. I like follow-up questions. The University' garden soil tests are excellent. https://soiltest.cfans.umn.edu/testing-services/lawn-garden This is how to find a tree expert. https://extension.umn.edu/planting-and-growing-guides/how-hire-tree-care-professional The Minnesota Landscape Arboretum is a wonderful place to see and learn about plants that grow in Minnesota. https://mngardens.horticulture.umn.edu/minnesota-landscape-arboretum Replied June 29, 2026, 2:56 PM EDT

Hey Steve,

Thanks for your help. I did attach a photo of a small leaf that fell off my tree last week during a storm. To me it really looks like the anthracnose, but my leaf looks a little more brown than black. But it could be because it is "new" and hasn't gotten to the black part. I may take a close look at other leaves on the tree. Let me know if I may be way off. Thanks for all your help and volunteering!

Thanks,

Dave

From: ask=<personal data hidden> on behalf of Ask Extension
Sent: Monday, June 29, 2026 1:56 PM
To: David Rowley
Subject: Re: Sugar Maple Leaf Black Spots (#0207137)

The Question Asker Replied June 29, 2026, 3:30 PM EDT

Thank you for writing back.
You could be sure of the diagnosis by using the plant disease clinic. There is fee for testing.
https://pdc.umn.edu/
Fungal diseases, including anthracnose, can be managed. https://pdc.umn.edu/
https://www.canr.msu.edu/news/maple_anthracnose
https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/insects-pests-and-problems/diseases/anthracnose/anthracnose-of-trees
https://ask.extension.org/kb/faq.php?id=933539
The question of management strategies would be made by an arborist, not the diagnostic clinic.
Best to you,

Steve Miles, Master Gardener, Hennepin County, (I am a volunteer human being: not a bot, not AI). I'm an avid gardener but not a degreed or certified horticulturist or arborist. I will do much better if you also send a photograph. I like follow-up questions. The University' garden soil tests are excellent. https://soiltest.cfans.umn.edu/testing-services/lawn-garden This is how to find a tree expert. https://extension.umn.edu/planting-and-growing-guides/how-hire-tree-care-professional The Minnesota Landscape Arboretum is a wonderful place to see and learn about plants that grow in Minnesota. https://mngardens.horticulture.umn.edu/minnesota-landscape-arboretum Replied June 29, 2026, 6:06 PM EDT

Sugar Maple Leaf Black Spots #937222

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