Something is shredding my arborvitae trunks
I'm in Anoka County. Some critter is shredding the trunks of my mature Arborvitaes, just near the house, leaving piles of bark on the ground. Trees are 30' tall and we planted them 30 yrs ago. So what is doing this and how do we stop it? 2 yrs ago it happened to a dwarf apple tree when we were on vacation.. that tree is slowly dying.
My first guess would be deer. Deer rub their antlers against trees, causing this kind of damage. However, they usually choose younger trees. You might also see some signs of feeding on the lower branches. Deer typically tear branches off the tree.
My second guess would be rabbits. However, rabbit damage looks tidier. Any eaten branches would be cut neatly at a 45 degree angle. You'd also see droppings.
Of course, it would be better if you could catch the critter in the act so you'd know for sure. I'd recommend putting up fencing around this stand of trees and wait to see if your arborvitae will recover.
Read here on dealing with deer:
If you don't think the problem is deer, try this diagnostic site: