This is Colorado, and there are lots of different animals out there. Many of them leave their signs on trees. Porcupines, voles, and squirrels may chew bark off for food or medication. Woodpeckers drill holes in thin barked trees like birch to drink sap and eat the insects that are attracted to it. Shrubs with shredding bark, like honeysuckles, may be stripped for nesting material by birds. Elk, moose, or deer may rub their antlers on trees, wearing the bark off.

Tree Damage

The location, height and pattern of the damage and even the type of tree can help reveal the animal responsible. Chewing or other damage that fully encircles a branch or trunk will result in the death of that limb above that damage. If the damage is to the trunk, this could include the death of the whole tree.

  • Squirrel Damage: usually shows as chewed areas, typically high in a tree and on the upper portions of a branch. As long as the damage doesn’t completely go around the circumference of the branch, the tree will probably be able to survive the wound.
    squirrel-damage
  • Porcupine Damage: can be quite extensive, the long chiseled tooth marks are distinctive. They tend to like fairly thin bark and will often sit on a branch where they can feed leisurely. They eat a variety of plants, including the foliage and bark of conifer trees. It’s particularly easy for them to strip the bark from conifer trees in the spring when the bark is relatively lose and pliable.
    Porcupine
  • Vole Damage: Voles are small, typically burrowing, mouse-like rodents. While voles do not climb trees, they may chew off the bark at the base of shrubs or small trees during the winter. Chewing that completely encircles a branch will cause that branch to die. Voles rely on the cover of snow, dense shrubbery, or mulch around the base of a small tree to access the bark. They may also chew the bark from young thin-barked trees in winter.
    VoleTree
  • Bird Damage: on honeysuckle or other shredded-bark shrubs can be quite extensive. Woodpeckers can wreak havoc on trees as well. Viewing the damage, it’s had to believe that a bird could be responsible!
    damage3

Control Measures

  • Voles can be trapped much like mice
  • Protect smaller trees and shrubs by keeping mulch away from the base in winter. You can also pack the snow down around trunks to block voles pathways under snow cover.
  • Use plastic tree protectors or chicken-wire cages around trunks.
  • Use a commercial animal repellent.
  • Use fencing or barriers.