When you see a series of 3- to 5-inch rounded, raised ridges breaking the surface of your lawn that are accompanied by tiny dirt volcanoes, you know you have moles tunneling below ground.
Moles cause little damage to the environment at large. Plus, they naturally aerate soils and eliminate the larvae of destructive insects. They only become a problem when they invade lawns and gardens, tearing up expanses of green grass and uprooting plants. Because mole tunneling destroys grass roots, the ridges brown quickly. The most effective way to get rid of moles is to kill them with a trap.
Moles are burrowing insectivores. They grow to be 6 to 8 inches long and have gray to black velvety fur, slender hairless snouts, and small eyes and ears. Moles' large front feet have long claws that dig much like a hoe. Except for breeding season in early spring, moles tend to live alone, so the multitunneled pattern in your yard is likely home to only one mole.
Moles build new feeding tunnels constantly and may not use the same one twice. You may find entry and exit mounds, which are usually round and symmetrical, pushed up volcano-fashion by the mole. The hole usually has dirt in it but remains visible.
The mounds are connected to main runways, which moles use repeatedly. The runways are 12-18 inches underground and not usually visible.
Moles feed on insects and insect larvae, but their preferred dinner includes earthworms and white grubs. Given a choice, moles pick moist, sandy loam soils over dry, heavy clay soils. They are most active during warm, wet months, although they live underground year-round.
Homeowners sometimes mistake mole tunnels for those made by pocket gophers, small rodents that also tunnel underground.
Gophers, however, do not create lawn ridges. They eat the roots of grass and other plants, pulling them down into underground burrows, which tends to push soil out to the side. Their tunnels look more flattened, with fan-shape or semicircular mounds. Each mound may contain a visible hole, although earth clumps can camouflage the hole.
Mesh barriers, traps, and poison baits can be used to eliminate pocket gophers. Avoid baits that contain strychnine because predators that eat the poisoned gopher may also die.
The only sure way to eliminate a mole is to use a mole-specific trap that will kill the animal. Repellants, poisons, fumigants, and home remedies are less effective.
Above- and below ground traps are available. Follow the package directions for correct placement, and move the tunnel traps daily if the mole is not caught. Try inverting a bucket over the trap to conceal the trap and prevent tampering.
Spring and fall, when the ground is moist but not frozen, are the best times of year for control because moles are most active then.
In all but the worst cases, removing just one or two moles usually solves the problem because moles don't live in communities.
Although moles like to eat grubs, using a chemical control against grubs won't get rid of moles because a mole's diet also includes earthworms (which are good for your soil) and other insects. Avoid using insecticides on lawns, as it may kill beneficial insects.
To protect small, enclosed areas such as a garden, you can use a barrier method. Bury a 24-inch metal or hardware cloth barrier at least 1 foot below the surface and bend the bottom out at a 90-degree angle.
Because moles like moist areas, you can try improving soil drainage to discourage them.
If the problem is not severe, you can simply wait it out: Moles live less than three years.