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Pruning a mature pin oak tree #822899
Asked March 20, 2023, 12:32 PM EDT
Oakland County Michigan
Expert Response
These photos of the pin oak were taken 3/20/23
Hello Laura
We had this question asked on Feb. 28th and here is MSU Professor, Forest Ecology, Deborah McCullough’s reply:
“Pruning oaks should not be a problem at this point( Feb. 28th). I would be very surprised if the tiny nitidulid beetles that can vector Oak Wilt are active yet. They would have to warm up to the point where they could fly - which takes quite a bit of heat accumulation. Then they would have to find a mycelial mat on a tree that died last year and the mat would have to be producing spores - too early and too cool for much of that. It is unlikely that many trees are producing mats, let alone spores. Given all that would need to happen, I think you have a month or so for pruning.”
Based on that, if you cannot prune before April 15, which is the beginning of Oak Wilt season, then do not prune until after Oak Wilt season ends — middle July or beginning of August. Waiting until after several freeze events in fall, through the winter, is the safest time to prune.
https://www.canr.msu.edu/news/smart-gardening-to-prevent-oak-wilt
If you must prune for a safety concern, then be prepared to immediately( in under 5 minutes) paint each cut on the tree with household latex paint. A pruner sealer may also be used but, household latex paint works as well.
( removing full name, piblic database)
From: Ask Extension <<personal data hidden>>
To: Laura Flanagan Sawyer <<personal data hidden>>
Sent: Mon, Mar 20, 2023 1:29 pm
Subject: Re: Pruning a mature pin oak tree (#0092827)