Q.Baby Apple Trees/Vole Damage
Last year I planted nine bare root fruit trees and this year I discovered major bark damage. The top layer of bark has been eaten away almost completely from the ground up to about six inches and nearly all the way around. Upon further investigation, I have discovered the demon of my orchard is a ‘vole’. My question is, since they are leafing up and producing flowers just as normal, could the damage I see be not as bad as I’m thinking it is? Or are these trees dead and just don’t know it yet?

Certified GKH Gardening Expert
Voles aremostly herbivorous, feeding on a variety of grasses, herbaceous plants, bulbs, and tubers. Voles do not typically eat tree bark up six inches high. Vole damage to tree trunks normally occurs from a few inches above ground to a few inches below ground. If the damage is below ground, you will need to remove soil from the base of the tree to see it. Gnaw marks about 1/8 inch wide and3/8 inch long found in irregular patches and at various angles, taken inconjunction with other signs (droppings, runways, and burrows), indicate vole damage. If voles are not the problem, then most likely your culprit is due to rabbits. Rabbits feed on and damage the bark and twigs of landscape plants. Their chewing can permanently disfigure or even kill a tree. Some favorites of rabbits include fruit trees, leafy vegetables, and grasses. As long as the trees are thriving, they should be fine. However, removing or reducing the vegetative cover around your trees will help deter these pests, and placing plastic or metal cylinders around the base of the trees (bury them a few inches below soil) should help alleviate any future damage.
This article will help with repairing tree damage: https://www.gardeningknowhow.com/ornamental/trees/tgen/repairing-tree-bark-damage.htm