Yea, I just said 75 since the two dozen isn't an exact count. It's most likely more. I've got some trees also that have gotten so big the no longer need the protection of a fence and have remove the fence from them and put it around others. I like the tire idea.
I've probably got a dozen or more old Semi tires. Three to a tree of them would probably work. Might even have as many as two dozen car tires. I'll put them to use.

as I said I won't say it works 100% of the time, but I know a lot of old time farmers that swear buy it
they even use them to fence off sections of fields to keep cows out as cows too I am told won't cross over a tire with the hole causing them worries about HOW deep

when scared though I am sure they will jump em
but to protect a tree from being rubbed, I see that maybe working out better a swill keep a deer a few feet back maybe and not close enough to rub things?
maybe not the most environmentally friendly deal, but something I thought I would share with you?

also, if you WISH to still use a liquid spray
I guess you can fill inside of tire with it , and will last longer maybe than just on a tree that was sprayed with it