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Oak trees #939538
Asked July 16, 2026, 8:41 PM EDT
Cass County Minnesota
Expert Response
Thanks for the question.
Your oak trees are obviously stressed. From your photos it looks like you may have two-lined chestnut borers. Your trees can be treated for this.
I recommend that you have a tree care professional come out to evaluate them and give you a recommendation. Only in person can they be sure what is going on here.
https://extension.umn.edu/planting-and-growing-guides/how-hire-tree-care-professional
https://hort.extension.wisc.edu/articles/two-lined-chestnut-borer/