I find that the mice borrow down underground right at the base of a tree and
chew the roots to ribbons and I have not been able to stop this. I can have
a
nice tree guard in place, but it can't protect the roots.
We have LOTS of hawks and owls and cats etc...but the voles are winning.
Mouse bait is a sometimes answer and have not noticed that it helps much.
My apples are especially at risk..though they seem to graze on plum and peach
bark often enough as well..
I guess since it helps keep the age of my orchard on the younger side I
should be glad as i use less of my ladders for trimming. :(
Karl Olson, Zone 5 sw Connecticut