Mounting a battle against mole hills

I have been bombarded with questions about moles, voles, and pocket gophers lately. Identifying which mammal is causing damage seems to be a major problem among lawn owners. Therefore I will try to explain differences among the signs so that you can tell what you are dealing with, should your lawn become home to one of these subterranean mammals.

Voles, or field mice, produce holes in the lawn or shrub bed that are a little larger in diameter than a quarter. No raised runs are present. In field situations where tall grasses have laid over in the winter, you can find surface runs, over which they move quite readily.

These surface runs also will be found when snow melts in the spring. Voles can run along the ground, below the snow. When the snow melts these often-used surface runs become evident.

Voles can cause considerable damage to trees and shrubs, because they feed on bark at the ground line. I have seen the stems of Christmas trees in plantations completely girdled by an infestation of voles. When food sources are scarce, especially in winter when snow and ice are present, voles can cause considerable damage to bark on the trees and shrubs in landscapes.

Moles are larger animals that spend most of their time below the soil surface. The most obvious sign is raised runs of soil found in your lawn or landscape. These raised burrows are made while looking for food. You also will find large mounds of soil in locations where they come to the surface.

Moles primarily feed on worms and soil insects although they will eat some vegetation. If moles are present in your lawn, you can rest assured that grubs, damaging lawn insect larvae, also are present.

Although gophers are found in this area, their population is not plentiful because we live on the extreme eastern edge of their natural range. Gophers produce no surface runs. Although their tunnels are usually 4 to 18 inches below the soil surface, some have been found as deep as 5 feet.

Gophers produce large mounds of dirt on the soil surface at the end of their lateral tunnels. These mounds are fan shaped, and have a distinctive plug of soil that fills up the actual hole into tunnels.

Gophers feed primarily on vegetation. They eat roots found while excavating their runs and surface foilage found near the surface mounds produced. They also are known to pull entire plants from the soil surface into their runs.

Although the signs produced by each mammal is different you can usually use similar control methods to eliminate them. For voles, place from three to five mole and gopher bait pellets into each hole. Do this on a weekly basis until no more new holes are found in your landscape.

For moles, tamp down all the surface runs that you find. The next day, look for new burrows that have appeared. Along these surface runs, place three to five mole and gopher bait pellets into the run at 5 foot intervals. Use a probe such as a stick or screwdriver find the tunnel in the mole mound and then place a few mole and gopher bait pellets into it.

If you have gophers in your landscape, you can place mole and gopher bait pellets in the mound that they excavate in a manner suggested above for moles.

Several gardeners have told me that they have successfully eliminated moles, gophers and voles by using a a fumigant. These "bombs" are ignited and a gas is produced which pervades in the runs of all three mammals. This product works best after a rain and in soils which have a high clay content. If you are working in porous soils, the gas will escape to the atmosphere readily, and no control will be accomplished.

Traps are generally successful for moles if handled properly. Most mole traps have detailed instructions on use on the package. A trap has been suggested for use on gophers, but these traps are not readily available for purchase.

Of course, there are other methods of control that have been suggested, such as the use of castor oil as a repellent, chewing gum, pinwheels and electronic vibrators. Reports of success or failure with these products are quite varied.

If you find burrowing mammal signs in your lawn or landscape such as burrows, mounds of soil or holes, try to identify the culprit causing the problem. Then use prepared mole and gopher baits to eliminate the mammal. If you prefer there are other methods of control that you can try.

Send your gardening and landscape questions to Paul Schnare at P.O. Box 699; Cape Girardeau, Mo. 63702-0699 or by e-mail to news@semissourian.com.