Pest profile: Moles

When you dedicate time and effort into maintaining a beautiful landscape, it can be disheartening to see that hard work torn up by moles' enthusiastic tunneling. The frustration moles cause is immense, and, as a result, incites people to try a wide array of techniques in an attempt to eliminate moles from a landscape. Unfortunately most methods employed are ineffective.

While there are seven species of moles in the U.S., the most common species in the landscape is the eastern mole (Scalopus aquaticus L.). Its range is the eastern portion of the country. Some portions of the eastern moles' range overlap with pocket gophers' range. It is essential to differentiate the two pests in order gain control.
 

Understanding Moles. Pocket gophers are rodents that create large irregular mounds. Unless the soil is shallow, the tunnels used by this pest are excavated below the ground and remain unseen. There will often be a plug to one side of the tunnel. Gophers eat plant material, so if chewed roots and missing plants are observed, then the problem is not moles.

A mole will spend most of its life underground feeding on invertebrate animals living in the soil. Its diet sharply reflects the diversity of the fauna found in its environment. In Arkansas, moles primarily feed on earthworms and insects, but elsewhere grubs may be the principal source of nutrition. Moles lack the dental structure to chew plant material for food, and, as a result, subsist strictly as a carnivore.

This has important control implications as most bait on the market cannot be consumed by moles.
 

Control Measures. By far the most effective, consistent control technique of moles is trapping. Trapping moles is not hard, but it does take some practice to find a good place to set a trap. The key to successfully trapping a mole is to locate a tunnel that is revisited often.

These tend to be below the surface, but are not necessarily deep. In Arkansas, we find this sort of tunnel about 4-6 inches below ground, but this varies by region.

Because tunnels are important in food collection, moles keep them open and clear. Mole traps work by using a blockage to a tunnel as a means of triggering a trap. Air flow, foreign objects and light may cause a mole to dig around a trap. As a result, soil makes the best blockage.

There are several traps available. The most common type used by professionals is the scissor trap. The scissor trap is widely used and has performed well in tests. Scissor traps are set into the ground around a tunnel blocked by soil.

Another effective method of mole control is the use of soft, worm-shaped baits. To properly use these also requires locating revisited tunnels and careful placement. Because they are poisonous and require nearly the same work as setting traps, these are best used in locations where traps cannot be visible such as golf courses and along public paths. Mole baits are not legal for use in many states.

With some persistence, it is possible to eliminate moles in your landscape. At first expect a 30 percent success rate with your control attempts, but over time this will improve. L&L

The author is county extension agent for Sebastian County, Ark.