What Are You Waiting For?

There are many reasons why mole control is a nice fit for pest control operators. First, the trapping techniques are not especially difficult (we probably are more challenged by some rat trapping programs). Second, the money is good, and third, the service fits into our route models. Besides, most of our questions on moles come from existing customers to whom we are already providing control services for insect or rodent problems. Why then, should we walk away from this service?

Therefore, the objective of this article remains much the same as the article which ran 10 years ago — mole control offers some great business opportunities. However, this article also provides updates in mole control techniques and considerations important for pest management professionals.

MOLE BIOLOGY AND BEHAVIOR. The origin of the word mole comes from “earth thrower.” Few mammals create as much frustration and anger around buildings as do moles when they tunnel through our turf, and push up dirt tunnels and unsightly mounds on top of the ground, ruining the look of well manicured turf.

The Eastern mole (Scalopus aquaticus) is the most numerous and widespread mole in the eastern half of the United States, (pictured above) whereas the Townsend’s mole (Scapanus townsendii) is the most troublesome species on the coast of Oregon and Washington. The broad-footed mole, (Scapanus latimanus) is a pest in some parts of California.

Because of their secretive and subterranean lifestyle, moles are among the most misunderstood of all mammals. Moles belong to the mammalian order Insectivora, and thus they are related to shrews. Shrews and moles feed mostly on earthworms, beetle grubs, ants, and other soil-dwelling insects and animals. A smaller part of their diet consists of various types of vegetation. But unlike rodents, moles do not eat roots, tubers, or flower bulbs, although they are often blamed for doing so by gardeners.

A single litter of three to five moles are born in the spring following a four- to six-week gestation period. The nests are enlargements of the tunnels and are typically located underneath the natural protection of boulders, trees, stumps and fencerows. Young moles grow rapidly and resemble the adults at about five to six weeks of age. Territories vary in size depending on the mole’s age and gender, and the abundance of resources in an area.

Mature males establish tunnel systems with lengths of up to 350 yards and containing two or more levels. Females construct systems of about 150 yards. Young moles typically use the “family” territory for several months before establishing their own independent tunnel systems. New territories often overlap parental or sibling systems or are relatively close nearby. When a mole dies, other moles in the area “absorb” the newly vacated system into their own.

Moles are active throughout all months of the year, but they are most active during the spring and fall on damp days or following rain showers. When the ground surface becomes frozen in the winter or very dry during the summer, moles use their deeper burrows. Activity periods consist of work and rest shifts alternating every several hours throughout the day and night. The greater portion of a mole’s 24-hour cycle, however, is spent sleeping or resting.

Two types of tunnels are produced by moles — surface runways and deep runways. Certain tunnels of both types are used as major lanes of travel (called main runways) and may be used by several moles in the area. Surface tunnels are commonly seen as the raised ridges running through lawn areas. These tunnels are typically only a few inches deep. The eastern mole is capable of extending surface tunnels at the rate of up to 100 feet per day. Surface tunnels may be used daily, may be revisited at irregular intervals, or may be used only once and then abandoned. Surface tunnels usually connect with the deep tunnels, which are located between 3 and 12 inches below the surface.

The deep runways are the main runways, since they are used daily as the mole travels to and from 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 horseshoe shaped.)

MOLE CONTROL. Many do-it-yourself home remedies are still used against moles. Out of frustration, homeowners insert chewing gum into the tunnels (thinking moles eat the gum, and the gum clogs their intestines!), pour obnoxious chemicals (ammonia, bleach, lye, etc.) down the tunnels, hook up car exhaust, flood the tunnels with water, and try other “weekend warrior” mole-war strategies too many to mention. But none provide any dependable control, and some probably kill or harm non-target organisms. Peanuts poisoned with strychnine and zinc phosphide are still available off the shelves in some hardware stores. But because moles are not rodents, nuts are not very attractive to them, and thus control with these types of products are not very effective. Many dogs have been poisoned over the years as a result of the dogs digging the nuts out of the tunnels.

Various chemical and mechanical repellents have also been tried to fend off moles. Ultrasonic machines and other electronic gizmos claiming to repel moles, voles, gophers and other mammals from yard and garden areas are still available through a variety of catalogs. Many homeowners still try spinning daises and vibrating windmills. The presumption is that moles which are seen actively tunneling in a yard, are noted to “freeze” in their tunnels when footsteps or some type of typical house noise occurs (e.g. lawn mowers, car motors, garage doors, etc.). But moles acclimate to repeating sounds (as do most animals and birds). I’ve watched moles continue to work while I was mowing the lawn within 10 feet of them. Sound repellents provide no value in controlling moles.

Several years ago a chemical repellent containing castor oil and detergent emerged as a mole repellent. One product, was field-tested by Michigan State University in 1994 and the researchers found some mole repellency in 26 out of 27 mole sites. But for pest management professionals considering offering mole control services, the callback potential associated with the use of a chemical mole repellent is likely to be significant.

The effects of castor oil are highly variable and depend on soil conditions, weather, area to be treated, and surrounding mole pressure. For example, a castor oil treatment is said to last between 30 to 70 days and may need to be re-applied after rain. Is a homeowner to consider possibly having the repellent applied once a month, March through October, and after every rainstorm in the spring and summer? Considering the wet spring experienced this year in many areas, this might mean several re-applications. Moreover, it can take from three to seven days for repellency to occur after each treatment. Thus, damage may continue while waiting for repellency to occur (if it even does). Considering this repellent costs approximately $ 60.00 to treat 40,000 square feet, it is hard to imagine fitting this chemical into a pest management professional’s program.

At best, chemical repellents may have utility when applied by homeowners on small turf or garden plots or those needing temporary protection until a more professional approach (i.e. trapping) can be conducted. But the choice to use chemical repellents are best left with homeowners. Whether they spend their money wisely or not for do-it-yourself pest control is their choice. Most of us know how that goes.

Still today, kill traps are the most cost-effective services a professional can offer their clients. With several mole traps correctly placed, the mole can be captured within a day or within a day or two, and both the current and future damage is halted. What is more, the customer can be shown the results of your effort. As this article is an update in mole control, a detailed discussion on mole trapping is not provided here. However, many excellent university fact sheets, trapper association booklets, and “how-to videos” are now available.

Overall, the key to successfully trapping moles, is to use several traps (e.g four to six per average residential job), and to place the traps in the mole’s high activity areas. These include areas such as fence rows, mulch beds and borders, and runways which follow structural borders. Professional mole trappers use both the harpoon traps and the scissors jaw traps. In most cases, when the traps are correctly set and well located, one or more moles are trapped by the very next day. For the inexperienced trapper, it takes a few times to learn how to “read a yard” for selecting the best places to locate the traps, but it becomes easier with time.

Because moles produce their litters in the spring (March through May), spring trapping programs are most cost-effective.

MOLES AND MULCH. Landscaping practices over the past ten years have resulted in an abundance of mulch being used around the perimeter of structures, and as a decorative cover and accent for gardens and trees.

Mulch beds result in providing many arthropods and other invertebrates with ideal harborage and the necessary moisture for their survival. It also protects these animals from the heat and desiccating effect of the sun.

Thus, many invertebrates proliferate and remain active and “working” the soil below the mulch. From the mole’s perspective now, the soil becomes less compact, porous, and rich in the foods the mole seeks. Consequently, moles are often found “patrolling” mulch beds and borders for fast food. In fact, I refer to mulch beds as McDonalds-for-moles. Has to be over a billion worms eaten — no doubt about it. Hence, mole trapping in and around mulch beds is one of the key areas to locate traps.

A while back, I spent a couple of days tagging along with a professional mole trapper from Cincinnati while he worked. His name is Tom Schmidt, AKA, The Mole Man. Tom is quite the craftsman when it comes to trapping moles. In fact, it would be hard to imagine anyone in the United States who has trapped more moles than Tom during the past 15 years. While we were driving along one day, Tom pondered as to how there are herds of cattle, packs of wolves, schools of fish, gaggles of geese and so on. His term for a family of moles: A dig of moles.

The author is a contributing editor to PCT.

SOURCES OF INFORMATION ON MOLES

For those wishing for more information on moles and how-to trapping guides, the following pamphlets, books, and videos are excellent.

Books
Gorman, M. L. and R. David Stone. 1990. The Natural History of Moles. Comstock Publishing Associates. Cornell University Press. Ithaca. 138 pp.

A comprehensive guide to the biology and behavior of moles with outstanding photographs and research data. Most of the emphasis is on the European mole. Some discussion on control.