deer chews bark

Asked May 21, 2018, 4:50 PM EDT

A few weeks after planting a Showy Mountain Ash, a deer chewed a significant amount of the tender new bark. Remarkably the tree survived the winter and looks healthy in spite of the exposed area. I am wondering if there is something I should do to protect the trunk, something that would seal the wound and protect it from insects and the hot sun. Thank you Ginny MacKenzie (651-489-2386)

Ramsey County Minnesota

1 Response

In general, if the bark is stripped more than 50%, a tree replacement may be warranted, but it sounds like your Showy Mountain Ash has survived the bark that was chewed off of it.

If the damage is restricted to one side, with less than 20 percent of the trunk girdled, then the tree may be able to heal over the wound during the next few years. Much larger wounds may never heal entirely. The exposed wood will be a target for insects and diseases. For now, trim away loose bark and branches. Take a sharp knife and cut off any jagged edges to promote optimal healing.

Do not use pruning sealer, tree-wound dressing or paint, as that instead will slow down the tree's own healing process.

Below are two more answers to your question from other extension associates that may be helpful to you:
-Sherry Schoewe MN MG
“It is possible that your tree will be ok. If the deer haven't eaten the bark going all the way around the trunk it should still be ok. It does depend on how big the trunk is and the size of the strip that is torn away. The eating of the branches isn't a serious problem usually. It does make the tree look unbalanced but it will regrow from the points where it was chewed. Wrapping the trunk with tree wrap in the fall is good to keep the rabbits, voles and deer from chewing on the bark. When the snow is deep it is difficult to prevent damage because the snow height allows them to reach higher. Sometimes a fence put around the tree about 3-4 feet out is about all that can keep the deer away. About all you can do at this point is hope for the best and if you can still wrap the trunk I would. There are also some sprays that deter deer and rabbits but they have an odor. Any damage done is not reversible and the tree will heal itself over so don't apply any paint or pruning sealer.”

-CHarker former Program assistant Fayette County, Kentucky
“As the saying goes, "once the damage is done, it's done." Once mechanical damage (including damage from weed whackers, lawn mowers, animals, etc.) has occurred to a tree trunk, all a person can do is wait to see if the tree will recover. Tree recovery is dependent on the extent of damage and the health of the tree before it was damaged. Once a tree has been subjected to this type of damage, however, its susceptibility to attacks from insect and disease pests goes up. Therefore, it is important to prevent other potential stressors from occurring at this time--so keep trees adequately watered, avoid other sources of mechanical injury, and consider applying some nitrogen fertilizer in the spring to improve plant vigor. Future deer damage can be prevented by wrapping tree trunks with commercial tree wrap, plastic tree guards or tall cylinders of chicken wire around the trunk of the tree.”

Below is a link to the University of Minnesota Extension website with useful information on “Coping with deer in home landscapes”:
https://www.extension.umn.edu/garden/yard-garden/wildlife/deer-in-the-home-landscape/

I hope this information is helpful to you.