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Maple tree, bark falling off #934465
Asked June 06, 2026, 4:50 PM EDT
Anoka County Minnesota
Expert Response
Thanks for the question. That is winter damage due to sun scald. Quite common on young maple trees, not so common on mature maple trees. No need to treat it. You can see that the inner bark is already starting to grow over the bare area. Without repeat damage it will eventually be totally enclosed. Here is a link to more information on sun scald: https://extension.umn.edu/planting-and-growing-guides/protecting-trees-and-shrubs-winter#sunscald-1263860
You need to protect/shade that trunk to prevent repeat damage in the future. I place a board (1x8 or similar, or cardboard) on the southwest side of the trunk for the winter/ December through April to prevent direct sunlight to the trunk. Smaller trees would use a white tube.
Paul -Tree Care Advisor volunteer