Control Tree Squirrel Damage

Control Tree Squirrel Damage

Tree squirrels are an attractive quarry to hunters wherever they are found. They are valued for their meat and fur. In 2006, Nebraska squirrel hunters harvested 17,500 tree squirrels. In addition, many people enjoy watching squirrels in public parks and in their own yards. On the negative side, tree squirrels damage personal property and cause an estimated loss of $500,000 per year to public power facilities in Omaha alone.

Flying squirrels are protected in Nebraska. Fortunately, they rarely conflict with human interests. Residents living in southeastern Nebraska should understand that activity by flying squirrels is frequently misattributed as mice.

Tree squirrels can cause a variety of problems, including damage to trees, flowers, lawns, gardens, vehicles and structures. Everyone who feeds birds is aware of the voracious appetite of tree squirrels for birdseed. On structures, the ability of squirrels to gnaw, enter small holes and climb a variety of surfaces make them a significant challenge. Squirrels can cause extensive damage to structural insulation and electrical wires in homes, vehicles and power lines.

Exclusion

Trim tree limbs at least 8 feet way from buildings to prevent squirrels from jumping to roofs. Failure to trim upper branches may simply allow a squirrel to leap down to the roof from a higher branch. To prevent climbing on buildings or trees, install three horizontal rows of porcupine wire spaced so that the points are 1-inch apart. Porcupine wire is extremely sharp. Prevent potential human injuries by installing the wire at least 9 feet off the ground. Plant seedless varieties of trees to lower the amount of available food to reduce squirrel populations.

Help for Bird Feeders

Despite popular belief, squirrels can be excluded from bird feeders. The key to squirrel-free feeders is to respect the athletic abilities of squirrels. A gray squirrel can jump sideways 8 feet, straight up 4 feet and down 15 feet and then hang on where it lands. Fox squirrels have similar abilities and present similar challenges.

Avoid hanging bird feeders from trees. Instead, use a large-diameter metal pole, with accompanying baffle, to elevate a bird feeder at least 5 feet off the ground and 10 feet away from branches or other structures from which a squirrel could leap. Hang the bird feeder by a chain or cable from an arm of a pole with a properly placed baffle. Alternatively, metal flashing or a stovepipe can be placed on poles below platform bird feeders. Bird feeders also can be hung from a horizontal wire with plastic pipe sleeves as protection on either side.

Greased poles and sliding two-part poles usually fail. Enclose an entire birdfeeder with 2-inch wire mesh to permit small birds to feed while preventing squirrels. Using squirrel-resistant feeders, such as those with weight-activated perches, can also reduce the stealing of seed by squirrels. Capsaicin, mixed with bird seed, may be effective in repelling squirrels.

Landscape Protection

Tree squirrels also cause damage to gardens, flowers and lawns. They chew on spring-planted potted plants, bury nuts in turf or landscaped areas, dig up seeds and bulbs of garden vegetables and flowers and eat ripened fruits and grains.

Wire mesh fences topped with electrified wire or mesh enclosures may be practical for keeping squirrels out of small areas. Electrified wires aren't recommended for use around children or pets. Little else can be done with squirrels in larger areas, other than removing the offending squirrels by cage trapping or shooting where safe and legal.

Repellents

Taste repellants, such as Ro-pel and capsaicin, can be used to treat seeds, bulbs and flowers not destined for human consumption. Polybutenes are sticky materials that repel squirrels by touch, but they are only marginally effective and are messy to use.

It is ill-advised to feed squirrels. Well-fed squirrels quickly fill available nesting areas and are more likely to invade structures. In addition, the gathering of squirrels by feeding may increase the transmission of sarcoptic mange among the squirrels.

Squirrels are susceptible to parasites, including ticks, fleas, bot flies and mange mites. The latter causes a disease called sarcoptic mange that produces scabs and severe hair loss. The scabs become thick and wrinkled, giving the squirrel a startling appearance. The disease can cause death by exposure. Sarcoptic mange mites typically are species-specific so mange doesn't ordinarily spread from squirrels to people or pets. Report to authorities any squirrel that is acting extremely aggressive or is convulsive. 

Stephen Vantassel
Wildlife Damage Management
Stephen M. Vantassel was a Program Coordinator for Wildlife Damage Management at the University of Nebraska-Lincoln. Among his many duties, Stephen was responsible for managing the Internet Center for Wildlife Damage Management, http://icwdm.org, the nation’s leading source for research-based wildlife damage information on the web.