Trimming Oak trees
When is the best time to trim pin oak trees to avoid spreading disease? I heard experts have altered their recommendation from fall/winter trimming.
Oakland County Michigan
You are correct that the recommended time to prune oaks is in winter when the tree is dormant. This is when the sap beetles are certain to be inactive and can no longer spread the fungus to oak trees. Early spring and summer are the riskiest times to prune, this is when the beetles are most likely to be active. .
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