I have several oak trees in my forested back yard that are in various stages of loosing a thick outer layer of bark, revealing thinner whitish bark underneath. Once this bark is lost, it doesn't appear to grow back. The the tree in the photo below is in the middle stages of this process: most of the other oak trees I have have nearly totally lost the thick bark (except for patches here or there), and a one or two haven't lost any.

I had the city arborist over a few years ago for a different reason, and he mentioned offhand that this didn't look normal. I believe he said my trees were Bur Oaks.

Is this condition normal, or is it the result of a disease or pest?

peeling oak tree bark

2 Answers 2


There seems to be new bark growing where the old has come off.

If the bald area extends right round the tree and there is no new bark growing underneath, the tree will not live long, but you don't mention any other visible problems with your trees so that seems unlikely. Your picture only shows half the circumference of the tree trunk, of course.

If there is new bark developing, there is nothing to worry about. The cause is probably that the trees have had exceptionally good growing conditions for a year or two, and the trunk is growing faster than the old bark can expand.

There are some fungus and virus diseases which cause this, but they are likely to produce either liquid oozing from cracks in the bark, or discoloured wood (e.g. bright reddish brown) on the bald patches. If that is the case, the only "cure" is to remove the tree before others nearby become infected as well.

Another option which has been observed is damage caused by squirrels - though why they do this isn't very obvious!

  • 1
    I think the whitish gray stuff is bark, it's just a lot thinner and has a different feel to it. Some of the trees pretty much only have that kind of whitish bark (like the background tree just to the left of the foreground tree in the picture).
    – Kaypro II
    Jul 16, 2020 at 1:18
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    I'll look for oozing, but I haven't noticed anything like that before. Do you have any websites that describe the diseases with pictures? I also have a ton of resident squirrels (probably due to the acorns). They're almost always up there throwing their garbage down at me.
    – Kaypro II
    Jul 16, 2020 at 1:23
  • That is odd. I've never seen damage like that. I'd suspect a windstorm a few years back, but the other trees look fine. Jul 16, 2020 at 15:09

To me, this looks like normal growth, these trees will go through the natural "shedding" process as they grow. Those trees do not appear to be even close to full-grown yet and if there are not small brown fungal spores that turn grey or black then that's good if you notice that they do contract the disease, unfortunately, the best thing to do is burn it and cut it out of the area. If there is any dark smelly fluid draining from the cracks in the bark The bark will usually fall right off then you could be dealing with something known as slime flux the recommended thing to do is drill a 1/4" hole into the tree and put a copper tube in to let it drain. I think you should be fine the new bark looks healthy

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