Gray squirrel gathering cedar bark for its nest

Occasionally we visit a property where something has been pulling bark off of trees. The owners are of course concerned that their trees will die and they demand to know who is responsible.

The Possible Culprits

There are a number of animals that sometimes remove bark from trees, ranging from black bears, to porcupines, beavers, rabbits, and squirrels. Deer can remove bark with their antlers during rutting season. Beavers and rabbits don’t climb so can only strip bark as high as they can reach. Voles and deer mice sometimes chew on the trunks of trees in winter, especially low, below the snow line (see Preventing Winter Lawn Damage From Voles).

In our region though, squirrels are the main culprits when bark is stripped from trees in residential yards. Fox squirrels are more likely to strip tree bark, although gray squirrels and red squirrels can cause the damage as well. Fox squirrels look like a cross between gray squirrels and red squirrels but they are larger than either one.

Squirrels Will Strip Bark and Clip Twigs

Squirrels tend to strip bark in late winter. They seem to prefer deciduous trees with a smooth bark but dozens of different trees are reported to have been damaged by squirrel strippers. The stripped areas usually measures ½ inch wide and 3 to 6 inches long and is usually on a horizontal branch rather than on the trunk. Trees can generally survive some stripping damage but if the trunk is girdled by more than 50%, the tree may die.

Squirrels also clip twigs in spring (for nest building) and early fall (to reach nuts or cones). Twigs or small branches that are 1/4 to ½ inch in diameter are sometimes clipped and dropped to the ground.

Why Do Squirrels Strip Bark?

No one is sure why squirrels remove bark but there are several possible reasons:

1. Collecting soft material to use in nest building.
2. Looking for food or additional nutrients in bark. For example, red squirrels like to clip branches of maples to get to the sweet sap.
3. Pregnant females may strip bark prior to giving birth as a distraction from the pain.
4. Just because they can and because they like to do it. Squirrels like to gnaw and for bored squirrels, stripping bark might be like popping bubble wrap for people.

If you have one or two squirrels or another animal that is damaging your trees, give Colonial Pest a call. We humanely trap and remove nuisance wildlife.

Photo Credit : lucycat | ©