Last updated: Feb-2004

Moles are 6”-12” insectivores that feed on grubs, millipedes, ants and earthworms. They do not hibernate and have a high metabolic rate so require lots of food. Their main foods are grubs and earthworms. Signs of mole infestation are mounded soil and heaved runways which are most visible in fall and spring. They do not eat roots or bulbs but their tunneling disfigures lawn and gardens.

What You Can Do

• Trapping is the most effective method of control.
• Less effective methods include baiting, gassing and repellents.

Biology / Identification

Moles have velvety blue-black to gray mohair-like fur, a slender snout, needle like teeth, with flattened feet ,claws and inconspicuous ears. They can grow from 6'-12" long depending on species. Moles may be distinguished from meadow voles, gophers, and shrews by their naked, pointed nose that extends well in front of the mouth. Small eyes and ears are concealed by fur. Their spade like forefeet are wider than they are long. Discharged mounded soil and heaved runways are indicators of this pest's presence. The Eastern mole is the most common mole found in the eastern US, the most troublesome species on the coast of Oregon and Washington is the Townsend's mole , the Broad-footed mole can be found in California.

The Eastern can be found from the Atlantic to the foothills of the Rockies and from Southern Canada to the panhandle of Florida. All moles can be damaging but the Eastern mole is by far the most widespread. It is better described as the common or grey mole. It is the strongest of the group and is most often associated with tunnels and or mole mounds by residential homeowners. Moles are not rodents, but belong to a group of mammals called insectivores. Moles have a very high metabolic rate and, therefore, have to consume large amounts of food.

Its diet is restricted to ground invertebrates such as grubs, millipedes, ants and the like. However, the mole's primary food source is earthworm, so trying to control white grub and lawn insects is no protection from mole activity. Moles have a very high metabolic rate and, therefore, have to consume large amounts of food. They mate during February and March, with a single litter of three to five young born later in the spring following a 6 week gestation period. Since moles don't hibernate (they store neither food nor fat) final dispersal can result in severe lawn damage until the lawn surface freezes in winter. Newborn females will mate the following spring and the cycle begins anew.

Habits

Moles are active day and night throughout the year, but they are most visibly active during the spring and fall on damp days or following rain-showers when they push up more tunnel's and mounds. When the ground surface becomes frozen in the winter, or very dry during the summer, moles use only the deeper burrows. They produce two types of runways (tunnels ): sub-surface runways and deep runways. They build vast under ground tunnels in search of worms, insects and nesting/living space.

Tunnels often shared usually average 6" below surface. Mounds form a row of excavations unlike the random excavations of a gopher. Certain tunnels of both the deeper runways and the sub surface runways are used as major lane of travel(main runways) and may be used by several moles in the areas. Sub-surface runways are feeding tunnels just below the soil surface and commonly seen as the raised ridges running through lawn areas. The mole is capable of extending these runways at the rate of 100 feet per day. Sub-surface runs may be used daily, may be revisited at irregular intervals, or may be used only once for feeding and then abandoned. They connect with the deep runways, which are located between 3-12 inches below the surface.

As a rule, few or no mounds are produced as a result of the production of sub-surface tunnels. The deep tunnels are usually main runways, since they are used daily as the mole travels to and form the main sub-surface runways or the nest. The soil excavated from the deep tunnels is deposited on the surface through short vertical tunnels in volcano-like mounds(Mole mounds should not be confused with pocket gopher mounds which are horse-shoe shaped.) The number of mounds or surface ridges present is no indication of how may moles may be present. On the average, one acre of land will support about two or three moles at one time. But areas next to large tracts or forested areas may be subject to continual invasions by moles because such areas may support many moles.

They have large appetites and may eat up to 100 percent of their body weight in one day. White grubs, earthworms, beetles, and assorted larvae are their principal foods. Moles feed primarily on insects that feed below the ground.

Moles are usually solitary, although females and young may share the same burrow. The tunnels that the mole makes while searching for food may be used only once or may be traveled repeatedly. Moles may be active during any time of the day and seem to prefer cool, moist soil (the same as that preferred by grubs and earthworms).

Moles do not eat the roots and bulbs of flowers and vegetables, a commonly held belief. Voles and shrews will attack the roots and bulbs. In fact, they may benefit these plants by feeding on grubs and worms that can damage them. However, the tunneling activities of moles may disfigure lawns and gardens

Recommended Measures of control

There are several methods of control on the market : baiting, gassing, repellents and trapping. Trapping is the most reliable method of mole control. With all the methods and particularly with trapping, patience and persistence are the key words. Trapping is usually easiest during the spring and fall with mole activity is at a peak. Trapping in the spring can also eliminate the pregnant females, reducing population. It is completely essential to locate the main runways for successful trapping or baiting. To identify main runways look for runways which:

• Follow more or less a straight course for some distance
• Appear to connect two mounds or two runway systems.
• Follow fence rows, concrete paths or other man-made borders or
• Follow a woody perimeter of a field or yard.
• Nest are commonly found along protected areas like fence rows or hedgerows

Resources

• Moles: UC Guide to Healthy Lawns

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