Several observations of tree bark damage like this have been reported to the University of Maryland Extension’s Home & Garden Information Center (HGIC) recently.
Q: I was walking in the woods near my house and noticed bark trimmed off a tree. It looked like a buck rubbing with their antlers, but it was up high, about 10 feet. A couple weeks later, I was in my back yard and noticed the same thing on one of my trees. Can someone please help me figure out what is going on? Thanks!
A: This looks like damage from woodpecker feeding. Judging from the bark pattern of the tree, this looks like an ash tree. Many ashes in Maryland are becoming infested with the invasive emerald ash borer (EAB). Taking a close look at the photo, it appears there are borer holes in the trunk where the bark was removed. The EAB larvae that feed on the nutrient transporting layers under the bark are a good food source for birds such as woodpeckers. This woodpecker impact is being seen and reported more and more frequently.
Emerald ash borer is a non-native invasive insect which has killed many millions of ash trees in the U.S. They are lethal to ashes unless pesticides are applied to trees in the early stages of an infestation and then once each year thereafter. Unless this is an extremely valuable ash tree, we recommend removal and replanting with another native species of tree.
Dead ash trees become very brittle and hazardous as soon as they die, and their removal can become expensive. You may want to remove affected trees before they die or immediately thereafter.
By HGIC’s Certified Professional Horticulturists
- Emerald Ash Borer | Home & Garden Information Center
- Goodbye Ash Trees of the Potomac: Emerald Ash Borer (EAB), Agrilus Planipennis | University of Maryland, Bug of the Week
- Saving Your Ash Trees From the Emerald Ash Borer Beetle: A Homeowner’s Guide | Maryland Department of Natural Resources
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