Homeowners are sometimes confused regarding what is causing damage to their lawns and flowerbeds. Many will blame moles for damage in their yards when a separate species, the vole, is the culprit. Moles are fossorial (found digging and living underground), and landowners most often see evidence of moles in the raised ridges, surface tunnels or mounds they create.
Voles are semi-fossorial (partly or sometimes found digging and living underground) and are most often noticed by runways through grass, thatch, mulch or leaf litter above the soil layer instead of by the raised tunnels produced by the burrowing moles.
Voles are rodents that feed on vegetation, fungi, fruits, nuts and seeds. Their runways are found in the deep thatch, mulch, loose dirt and leaf litter. They often leave grass clippings behind in these runways. Voles will enter short underground burrows to nest; however, their runways are mostly above the surface of the soil.
The most identifiable sign of voles is their extensive surface runway system through flowerbeds or lawns. Voles are active both day and night year-round. They do not hibernate and continue to feed and produce tunnels beneath snow.
Landowners most often notice vole damage by finding girdled plants or shrubs and trees that are gnawed on right at, or slightly above, ground level. Voles will climb up into vegetation and bite off branches, or feed on fruits and vegetables.
White-tailed deer are often blamed for vole damage. Deer do not have upper incisors and will leave a small tendril of vegetation when they bite and tear the plant.
Voles have pronounced upper and lower incisors resulting in a clean cut. Voles will eat small portions of fruits and vegetables, leaving them on the vine or stem. Deer, however, normally break fruits and vegetables off the stem or vine.
Habitat modification practices, such as removing thatch, leaf litter or mulch, in areas that support voles can reduce the likelihood of vole damage. Regularly mowing lawns or turf to reduce grass height and cover can also help reduce vole damage, as can clearing mulch from flowerbeds or around the base of trees to a 3-foot radius.
Hardware cloth can be used to exclude voles from seedlings, trees and shrubs. The mesh size should not be any larger than ¼ inch and it may need to be buried about 6 inches to prevent voles from burrowing under.
Trapping can be effective in areas of small vole populations. Place mouse snap traps perpendicular to runways with the trap pan in the runway. Pieces of apple or peanut butter and oatmeal can be used as bait for voles, but a non-baited trap will also work.
Toxicants to control voles are available at your local home and garden stores. Use these with extreme caution, as non-target animals, such as pets and beneficial animals, may pick up the toxic bait or eat the contaminated carcasses of deceased voles.