Moles
An eastern American mole (Scalopus aquaticus Linnacus). Photo by Kenneth Catania, Vanderbilt University. Courtesy of the National Science Foundation.
Moles, and the tunnels they create, are often considered a garden nuisance. These small rodents have pointed snouts and tunnel underground searching for a meal of insects and soil invertebrates. While their tunnels are an annoyance to most, some people consider these tiny mammals beneficial since they feed on potentially harmful insects like mole crickets, grubs, ants, and slugs.
Characteristics of mole damage are saucer-sized mounds of dirt and holes with a 2–4 inch diameter. While the damage from their tunneling is usually aesthetic, it can temporarily cause plant roots to be disturbed and dry out. If you're one to look on the bright side, consider that the moles could be eating true garden pests, and the tunneling loosens and aerates the soil. If you can find it in your heart to tolerate the moles in your landscape, simply press down the disturbed soil and go about your business.
Many home remedies exist that claim to rid your lawn of moles. The truth is that most of these quick fixes are not actually going to deter moles from tunneling through your landscape. In fact, some of these ineffective mole "control" measures could actually make the problem worse. For example, the castor bean seeds some people swear by can sprout and cause problems in your garden.
Mole Deterrents and Traps
If you wish to rid your landscape of moles, there are a few things you can try in order to deter them from tunneling. First, be proactive; moles prefer to tunnel in damp soils, so be sure you aren't overwatering your lawn.
Trapping is the most effective way to end mole tunneling in your landscape. There are a number of different traps designed for use with moles that you should be able to purchase at your local garden store. Be sure to set up your traps at active tunnels. Be aware that most mole traps are lethal, so have a plan for mole disposal before setting your traps.
If trapping moles isn't your cup of tea, you can also use rigid physical barriers, like hardware cloth or sheet metal, buried 1.5 feet beneath the ground. This works well if you want to keep moles out of a particular area, although it's impractical for use in your entire landscape. You can also look into commercially available chemical repellents suitable for nuisance animals. Be sure to look for a product that is specifically designed to deter moles.
Some homeowners might think to use pesticides to kill the insects that moles feed on as a method of control, but this is strongly discouraged. Using insecticides in this way is both inefficient and harmful to the environment.
While some gardeners choose to live with the moles and their tunnels, it's understandable why so many want to remove these nuisance animals. If you have questions about using traps or deterrents to discourage moles from tunneling in your landscape, contact your county Extension office.