White Pine Sapling - What causes this?

Hi All,

First time posting here, thanks for having me.  My family and I live in Jefferson County PA and we have a bunch of white pine trees on our property.  I was on a walk last night and I noticed that one of the saplings, maybe about 9' tall, has bark removed around almost the whole top of the tree like 7' off the ground.  It looks almost like a deer rub, but that obviously seems impossible.  I attached some pictures for reference.  Would love any feedback on what type of critter, bug, or animal could do this?  I didn't notice it on any other trees.

Thanks for your help!
Piney

I'd guess a porcupine, since that's what they like to eat, but I read that can groundhogs also do this, incredibly.  You'd think with the name "ground" hog...  This person had a very similar looking problem and only saw raccoon tracks, though.  But the extension person thought it was likely a porcupine:

What's gnawing the bark off our pine limbs?



Here's a site that tells what porcupines eat and their lifestyle:

Porcupine info

And one caught in the act:

Thanks so much!  Never would've guessed that was the answer. Really appreciate your time! Have a great day.

Kim Goodwin wrote:I'd guess a porcupine, since that's what they like to eat, but I read that can groundhogs also do this, incredibly.  You'd think with the name "ground" hog...  This person had a very similar looking problem and only saw raccoon tracks, though.  But the extension person thought it was likely a porcupine:

What's gnawing the bark off our pine limbs?



Here's a site that tells what porcupines eat and their lifestyle:

Porcupine info

And one caught in the act: