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Crab apple tree #870890
Asked May 31, 2024, 7:38 AM EDT
Carver County Minnesota
Expert Response
Thanks for the question. What you describe is apple scab. A fungal disease very common on older varieties of crab apple trees. Typically, will not kill the tree. Crab apple trees are typically grown for their spring beautiful blooms. So he could leave it and enjoy the spring show. He could replace it with an apple scab resistant variety. Here is a link for more detailed information: https://extension.umn.edu/plant-diseases/apple-scab
Paul
Tree Care Advisor volunteer