We have had many complaints about ground squirrels this year. Here are a few tips.
It is easy to identify ground squirrels, since they forage above ground near their burrows. Their fur is brownish gray and speckled with off white along the back. Although ground squirrels look similar to tree squirrels and can climb trees when frightened they always will retreat to a burrow.
Ground squirrels live in a burrow system where they sleep, rest, rear young, store food and avoid danger. They are active during the day, mainly from midmorning through late afternoon, especially on warm, sunny days. During the winter months most ground squirrels hibernate. During the hottest times of the year most adults go into a period of inactivity that can last a few days to a week or more.
Ground squirrels damage many plants including ornamentals, fruit and vegetables. They can damage young shrubs, vines and trees by gnawing bark, girdling trunks, eating twigs and burrowing around roots. They also will gnaw on plastic sprinkler heads and irrigation lines. Their burrows can be quite destructive and hazardous to people, machinery and livestock.
Squirrels can harbor diseases. If you find unusual numbers of squirrels or other rodents dead for no apparent reason, notify public health officials. Do not handle dead squirrels under these circumstances.
The control procedure you select depends heavily upon the unique life cycle and behavior of the ground squirrel. For example, baiting with treated grain is effective in summer and fall, because squirrels feed on seeds during this time. Fumigation is most effective in spring when moist soil helps seal gasses in the burrow.
Traps are practical for control when numbers are low to moderate. Set the traps correctly. Live-catch traps are not recommended.
Fumigation is a relatively safe method of control. As with any pesticide, read and follow label instructions. Fumigants are used when the squirrels are active and the soil is moist.
Toxic baits are also available.
— For more gardening information go to cecolusa.ucanr.edu/Master_Gardeners.