Plum Tree bark issue

Question: Hello. We have a Mt. Scott plum tree in a sunny area of our back yard. It was planted about 4 years ago, and has done well, even producing plumbs the year before last. During a very cold spell this past winter we wrapped it with tree wrap (which may or may not have been a good idea). We just removed the wrap and discovered a sizable section of bark on the north side (photos attached) where the bark is missing and there are what looks like insect trails on the bared tree. Do you know what this might be, and how should we treat this to help this tree recover/survive? Thank you!

responder: Hania Oleszak  Replied March 30, 2023, 12:51 PM EDT
response: Hi there, This damage appears consistent with squirrel damage - is it possible that squirrels were able to get beneath the tree wrap? Here is a blog from Ohio State that gives different examples of squirrel damage, just to get an idea of what that can look like. Here is another resource that describes how to manage squirrels in the future (https://tfsweb.tamu.edu/uploadedFiles/TFS_Main/Urban_and_Community_Forestry/About_Urban_and_Community_Forestry/Urban_Forest_Information_Sheets/Tree%20Health%20-%20Injury_Squirrel%20and%20Other%20Small%20Animals.pdf), but, unfortunately, the damage that has been done, is done. Luckily the damage doesn't span around the entire trunk which would girdle the tree, but it still may be large enough to cause issues for the tree down the road. Let me know if you have any other questions! Hania

responder: The Question Asker Replied March 31, 2023, 4:58 PM EDT
response: Hello,Thank you for your reply. I don’t think it is squirrel damage. The wrap was too tight for a mouse, let alone a squirrel. I am attaching a close-up picture. In addition to the bark missing, it looks like there are tracks or trails on the bare wood, which seems like insect damage of some sort.Thanks for taking another look!Joe Fretz Sent from Mail for Windows From: Ask ExtensionSent: Thursday, March 30, 2023 10:51 AMTo: jnelfretzSubject: Re: Plum Tree bark issue (#0093766)

responder: The Question Asker Replied March 31, 2023, 4:59 PM EDT
response: Hello, Thank you very much for your reply. I don’t think it is squirrel damage. The wrap was too tight for a mouse, let alone a squirrel. If you look at the pictures I originally attached, in addition to the bark missing, it looks like there are tracks or trails on the exposed bare wood, which seems like insect damage of some sort. Any other thoughts? Thanks for taking another look!

responder: Hania Oleszak  Replied March 31, 2023, 7:09 PM EDT
response: Hi Joe, I believe the tracks/trails you're seeing are actually incisor marks from a critter. For reference, here is another resource that shows similar damage from a porcupine gnawing on the bark: https://extension.usu.edu/forestry/publications/utah-forest-facts/038-porcupine-damage-to-trees. The incisor marks left by squirrels, as well as rabbits, are usually about 1 cm wide (smaller critters, like voles and mice, leave marks closer to 4 mm wide). How wide are the marks you're seeing? How far above the ground is the damage? Did you notice the damage immediately upon taking off the tree wrap? Is it possible that the damage was there before you put on the tree wrap or appeared after taking off the tree wrap? Thank you! Hania

responder: Hania Oleszak  Replied March 31, 2023, 7:14 PM EDT
response: Another consideration is that this could be a result of deer feeding/antler rubbing - the answers to the questions above might help us figure that out! Hania

responder: The Question Asker Replied March 31, 2023, 7:53 PM EDT
response: Thanks again for your reply. The questions you ask are great, and I will try to answer them:The individual marks are about 1/16” wideThe damage starts about 10” above the ground, and extends up to about 25” above the groundI noticed the damage immediately upon removing the tree wrap. However, I wrapped the tree in the dark in about 10 degree temperatures, so it is very possible I was not paying attention to or didn’t see them if they were there before.We do have groups of deer move through our yard every few weeks, sometimes more often. And we did have an incident years earlier where a deer had rubbed his antlers along the trunk of a young maple tree, causing significant damage.Hopefully this information will aid in narrowing down the options for avoiding similar damage to this tree in the future. Another question I have is would it help to wrap the tree again for awhile, to avoid incurring more damage? Thanks!Joe Fretz Sent from Mail for Windows From: Ask ExtensionSent: Friday, March 31, 2023 5:14 PMTo: jnelfretzSubject: Re: Plum Tree bark issue (#0093766)

responder: Hania Oleszak  Replied April 04, 2023, 4:38 PM EDT
response: Hi Joe, Thank you for your replies! Damage from antler rubbing often occurs on trees up to 3 feet off the ground, and typically occurs on younger trees that have thin, smooth bark. Considering that and the fact that you do have groups of deer that travel through your area, it seems likely that this is, in fact, damage from antler rubbing.  This happens most frequently in fall/early winter, when bucks are trying to remove the velvet off of their antlers, so I imagine the rubbing occurred before you put the tree wrap on.  For future protection, the best defense is exclusion of the deer via (tall!) fencing. As that isn't always possible, materials that create a physical barrier between the deer and tree are other helpful management practices (i.e., tree wrap, stakes around the trees, etc.). Installing these barriers during times of higher deer activity/antler rubbing (fall-winter) should suffice, so I don't think you need to wrap the tree again at this time. There are various repellents and deterrents on the market, but these have not shown to be effective long-term. Hopefully this helps! Hania