how high up the tree is the damage ... in other words.. how big of an animal would it have to be???

can we rule out exuberant children?

in regard to this alone.. there is nothing to do ... once exposed to the air.. it should weather to match other stuff ... how long it takes.. who knows ...

the odds of 3 trees in a group would all have the same damage.. is significant to me ... that 3 would suffer some malady all at the same time.. seems a bit coincidental ...

ken

I totally agree with
ken_adrian Adrian MI cold Z5

Hope that's not an ash -- borers pushing out of the wood makes infected ash trees look like that. Woodpeckers or nuthatches can sometimes peck under & release loose bark pieces -- seen that happen on white oaks.

I just googled it and read that some animals like squirrels, voles and porcupines may chew off bark for food or medication. And to stop them wrap the tree with something. I have stopped my beloved little squirrels that like to nibble on my Cut Leaf Japanese Maple by smearing some Vaseline with fine ground cayenne hot pepper in it on the branches and they leave it alone now and stick to the seeds I give them. For a large tree like yours I would wrap it with some chicken wire for a year or so to break the habit or spray it with a product that would not be notices like ugly as Vaseline with hot cayenne pepper. I bought a brand called "I Must Garden" , "Squirrel Repelant and sprayed other trees with it. and it seems to work. (photo below) I got it on amazon.

The animals are just trying to survive, so I only use these deterrents when necessary and live and let live. But note the spray has to be replenished after a rain, and the Vaseline and cayenne do not...and is cheaper! Hope this helps.

Most of the dead leaves on the ground are oak.

Wow I found a photo of an ash with bark damage that looks like red pinkie photo- but it was an Ash. Not an Oak, and there are a lot of Oak leaves at the base of the tree. Interesting to learn about all the same.

https://dnr.maryland.gov/forests/Pages/ForestHealth/Signs-of-Emerald-Ash-Borer.aspx

So
floral_uk z.8/9 SW UK's obeservation of Oak Leaves and
mad_gallica's info on boring insects put me on the trail of Oaks, and I found this photo and article from Davey Trees:

https://blog.davey.com/2018/09/what-causes-tiny-rows-of-holes-in-tree-trunk-maple-oak-apple/

The main difference between animals or kids doing this and insects seems to be HOLES.

So, red pinkie look for holes as a clue to the origin of your damage.

What mad gallica said. This is a white ash (Fraxinus Americana) and the “blonding” or lighter patches caused by damage to the outer bark as woodpeckers try to get at the emerald ash borers inside and the bark coming off in chunks are indicators that your trees are infested with Emerald ash borer, a nonnative insect that is decimating ash trees. You can see the borer holes in your second photo. Once they have gotten to this stage, there is nothing you can do to save them. There is an insecticide that can be injected into healthy trees to prevent the damage, but yours are not able to be saved at this point.

Sorry for the bad news, but it has been a problem here for several years, and this is an unfortunately familiar sight to me. On Friday I went walking in the woods on someone else’s property and all the ashes looked like this. On my property DH took down the remaining ash and fumed the wood to kill the larvae after turning it into cordwood.

That's sad about walking in the woods and seeing the Ash trees dying. I have an old Linden tree with a ton of holes in horizontal lines but no falling bark...do you know if Ash borer can get to Lindens too?

No, ash borer doesn't attack Lindens. Holes in horizontal lines sounds like Sapsucker. We don't have them here but I've seen pictures on these forums.

As Floral says. Sapsuckers don’t cause permanent damage, and one interesting fact about them is that as hummingbirds head north, often before there are many blooms, they rely on the fresh sapsucker wells for some of their food.

NHBabs z4b-5a NH and floral_uk z.8/9 SW UK Thanks for that Sapsucker info. Glad I don't have Ash Borers, and I do have hummingbirds so that's interesting to learn that they can use that as food, although I do have feeders out early each year.