Tree Squirrels

SANTA CLARA COUNTY has three (3) species of tree squirrels. The native Western Grey and the introduced Eastern Grey and Eastern Fox Squirrels. All three squirrels may cause damage around homes and gardens. Squirrels will gnaw on electrical wiring and gnaw through shingles and other roofing materials to gain access to homes. All three squirrels will occasionally build nest in attic spaces of houses. In yards and gardens they will gnaw the bark of trees and ornamental shrubs, sometimes doing considerable damage. In gardens, squirrels may eat newly planted seeds or seedlings. Yard lawns may be damaged as squirrels dig holes to hide nuts for later use. Squirrels will take food from yard bird feeders. Squirrel activity occurs during the daylight hours and tree squirrels in residential areas may be seen running along power lines, moving about on back fences, in trees and foraging for food on the ground.

The Eastern Fox Squirrel is rather large, 18 to 23 inches long and up to 2.25 pounds. Color patterns are variable. The most common bay area color seems to be a russet color coat and reddish tail although all black individuals are seen.

The Eastern Grey Squirrel is smaller, 18 to 20 inches and up to 2.25 pounds. The color pattern is usually a white underbelly with upper parts grey with a reddish wash.

The Native Western Grey is the largest of the three (3) tree squirrels at 20 to 24 inches and up to 2.75 pounds. The color is white underbelly with a silvery grey uppercoat.

These squirrels will have 2 broods a year in times of abundant food with usually about three (3) young per litter. Litters may occur in mid December to late summer depending on species.

Control of tree squirrels

NO POISON BAIT is registered for use against any tree squirrel. Trapping may be done with permits from California Department of Fish and Game. The best form of control is habitat modifications and squirrel proofing:

  • Close openings with 0.25 inch hardware cloth or make other suitable repairs.
  • Prevent squirrels from traveling on wires by installing two-foot sections of lightweight 2 - 3 inch diameter plastic pipe. Slit the pipe lengthwise, spread opening and place over wire The pipe will rotate on the wire and cause traveling squirrels to tumble.
  • Trim trees appropriately to prevent squirrels from jumping onto roofs.
  • To prevent squirrels from climbing trees, encircle them with a two-foot wide collar of metal six feet from the ground.
  • Human hair from a barber shop seems to be as good a repellent as any, when scattered around nest in attics or other parts of a building.
Last Updated: Apr 20, 2012