Tree squirrels are simultaneously among the most beloved and hated of suburban and urban wildlife, as their antics can draw both admiration and scorn from homeowners. While squirrels are undoubtedly fun to watch, the truth is they can cause significant damage to both ornamental and nut-producing trees. Below is more information on tree squirrels native to the Chicago area, what kind of damage they can produce, and what can be done to prevent them from harming trees.Understanding Squirrels and How They Can Cause Harm to Your Trees

The Squirrels of Chicago

There are four tree squirrels native to Illinois, and though they look similar, there are distinct differences between the species. Below is more information on the four species.

Fox Squirrel

The king of all tree squirrels, fox squirrels are the largest species in North America. Fox squirrels are identified by their rust-colored fur and long body lengths that can exceed 20 inches. Fox squirrels inhabit both rural and urban areas and can be found in the hearts of cities and towns.

Gray Squirrel

The gray squirrel is distinguished by their monochromatic fur colors: white, gray, and even black at times. The second largest squirrel, adult gray squirrels can weigh between one and one and a half pounds. Gray squirrels are also quite successful in adapting to the urban landscape and lifestyle.

Red Squirrel

A much smaller squirrel that rarely exceeds one half of a pound in weight, the red squirrel has decidedly red fur and is not common in urban areas.

Flying Squirrel

The smallest of all Illinois species, the flying squirrel is known for its remarkable ability to glide from tree to tree. This species is also rarely seen in an urban habitat.

Lifestyles of the Tree Squirrels

Both fox squirrel and gray squirrel females are capable of having two litters of offspring per year, and each litter contains anywhere from two to four pups. Squirrels will typically nest inside tree cavities or create nests using twigs and other materials, and the young will remain in the nest for two months or longer before venturing out on their own.

Squirrels are active in the daylight hours, unlike other many rodents, and will spend their time endlessly searching for food to eat or store. If food becomes scarce in a given area, squirrels have been known to wander dozens of miles to search for new habitats.

The Downside: How Squirrels Can Become Nuisances

Unfortunately, squirrels can be a big source of trouble when it comes to trees. Since fox squirrels and gray squirrels are both inhabitants of urban areas, their actions are particularly problematic. Here are some of the ways squirrels can damage or even kill trees.

Stripping Bark

Squirrels will consume tree bark, especially if there is strong competition for available food. This bark removal can make trees vulnerable to parasites and microorganisms that enter through the exposed xylem.

Eating Buds

The tender buds of emergent tree limbs and leaves are vulnerable to hungry squirrels. If too many of these are eaten on a particular tree, growth of the tree is stunted and could result in disfigurement of the tree, as well.

Consumption of Nuts

The tendency for squirrels to harvest nuts in large amounts can be a problem for people who collect them for food or other purposes. In areas where trees reseed without human involvement, squirrels can actually hinder normal reproductive processes by removing too many nuts.

What Can Be Done about Squirrels and Your Trees

If you are experiencing problems with squirrels damaging your trees, then you will need to contact a tree service for help. There are several actions that can be taken to keep squirrels from doing grave harm. For example, trees can be fitted with large metal bands that make climbing difficult or impossible.

In addition, special chemical repellents can be applied to keep squirrels away from your trees. Or, depending on the location of the tree when compared to other structures or power lines, limbs can be carefully trimmed to prevent squirrels from gaining easy access.


It’s best not to hesitate when facing squirrel trouble. Tree services can provide guidance and concrete assistance with the problems caused by squirrels and will help rehabilitate trees that have already been damaged.