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WHAT IS WRONG WITH MY RED OAK TREE #931841

Asked May 15, 2026, 2:48 PM EDT

MY RED OAK, WHICH IS CLOSE TO TWO SMALLER OAKS, IS DYING. IT IS ABOUT 2 FEET IN CIRCUMFERENCE AND HALF IS DYING. THE BRANCHES ARE FALLING. I WILL INCLUDE THREE PHOTOS AND I HOPE YOU CAN IDENTIFY THE DISEASE. THANK YOU!

Ramsey County Minnesota

Expert Response

Hello Steven, I will send to you links from the DNR and from U of M Extension.  Oak wilt needs to be diagnosed definitively by a lab such as the U of M Plant Disease clinic.

https://extension.umn.edu/plant-diseases/oak-wilt-minnesota

https://www.dnr.state.mn.us/treecare/forest_health/oakwilt/identification.html

Address: Stakman Hall, 1519 Gortner Ave #105, Falcon Heights, MN 55108Get There:22 minPhone: <personal data hidden>  for the plant disease clinic.  I would contact them ASAP.

For future reference, avoid pruning oaks between April and July when 1 of 2 sap beetles can transmit the fungus:  immediately paint any oak wounds ; and avoid moving firewood.  I hope that you can save some of your oak trees.

Joan Replied May 15, 2026, 5:28 PM EDT

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