Q:
Moles are burrowing through my garden, and they have eaten almost all the roots of my plants. How do I get rid of them? Do owls find moles a delicacy?
Susan Tawfik, Fairfax Station, VA
A mousetrap is one way to rid your garden of voles.
Photo/Illustration: Christine Erikson
A:
Tanya Drlik, I.P.M. specialist at Bio-Integral Resource Center in Berkeley, California, replies: I don’t believe that moles are your problem. They are carnivores that feed on earthworms, beetles, ants, and lawn grubs, and only damage plants inadvertently when their tunnels disturb roots or bulbs. Try to think of moles as beneficial animals in your soil because they act as aerators and move subsoil closer to the surface, where its nutrients are more available to plants.
It sounds more like voles are feeding on your plants. These small, stocky rodents—sometimes called field or meadow mice—feed on a wide variety of plants, seeds, bulbs, and rhizomes and can girdle trees by feeding on the bark. They travel on surface runways that connect their shallow burrows. The runways, and the fact that voles don’t leave mounds of excavated soil at the entrances to their burrows as moles do, are important clues of their presence.
Ridding a garden of voles is not easy. There are no effective repellents, and large scale fencing is impractical. Modifying their habitat may help. Voles like to have cover when traveling aboveground on their runways, so remove weed-control fabric, keep mulch to 1 inch or less, mow your lawn often, and open up your flower beds so voles will feel more vulnerable to suburban predators like cats and raccoons. It has been noted that owls feed on voles, but while they can help prune the population, they will not eliminate it.
Voles can be trapped using old-fashioned mouse snap-traps set perpendicular to the surface runways with the trigger positioned in the runway. Be sure that the trap is not wobbly—you don’t want the vole frightened by any movement. Peanut butter or oatmeal make an attractive bait. Voles can carry disease, so don’t pick them up with your bare hands. Also, to prevent birds from toying with your traps, camouflage them with grass clippings or a shoebox.