Molehills in home lawns look like mountains to some homeowners

Yards are greening up and molehills look like mountains to some homeowners making early lawn mowing passes.

I often receive calls from homeowners having consternation with moles. Their first reaction is typically to get out the roller and flatten everything out. What people may not realize is that the flattening process, especially with heavy rollers and saturated or clay soils, can cause soil compaction and increase soil moisture stress to grass plants in summer. So, your actions may be to the detriment of healthy grass. If you must use a roller, use a light one when conditions would be right to work soil for a vegetable garden. I once saw a picture of a guy using a road construction-size steam roller on his lawn (staged or not, I don’t know). Do I really need to explain how damaging that would be, with effects lingering for many years, and potentially decades?

So, what can you do to control moles?

A common misconception about mole control suggests that if you control grubs, you’ll take care of the moles. Grubs make up only a portion of the mole’s diet, which also includes earthworms and other soil animals. Moles may not move far from a treated lawn and may periodically re-invade the area in search of food or a mate.

Trapping is the most reliable method of mole control. However, it does take practice, patience, persistence and perhaps a bit of luck. Mole traps are available at several local retailers. Two main types of traps exist: the harpoon trap and the scissor trap. The harpoon trap has the trigger placed on the soil surface over a slightly depressed mole run. When triggered, spikes impale the mole vertically down. Scissor traps are placed in the mole run. A trigger in the middle of the trap enables capture of the mole via scissor-like jaws whether he advances or retreats. Other trap designs may also be available. Choose a well-used mole run to set one or more traps. In general, multiple traps increase your chances of success.

Until recent years, most mole baits have provided inconsistent results. However, a product introduced a number of years ago has shown some effectiveness. It mimics a favorite food of moles: earthworms. When the poison gel-type “worm” is placed inside a mole run, the mole consumes the poison worm and later dies. The product typically contains the active ingredient, bromethalin. Be sure to read and follow all label directions, and heed precautions. Several brand names now offer this product.

For the not-so-do-it-yourselfer, you can always hire someone to do the dirty work. A list of Nuisance Wildlife Control Operators that serve various Indiana counties is available at in.gov/dnr/fishwild/2351.htm. Of course, a fee is involved for their products and services.

Other mole control options include direct removal, live capture, using predators and employing mole barriers to protect an area like a garden.

To understand moles, first realize that moles are not rodents, like voles, mice or rats. They belong to the group of mammals known as insectivores, and thus are related to the shrew. They eat earthworms, white grubs, ants and other soil insects. And, they hunt their food in shallow burrows through lawns and other areas.

Moles are most active in yards in spring and fall, and after rain showers. They use deeper burrows in dry summer conditions and in winter. Mating occurs during February and March, with a single litter of three to five young born later in the spring following a six-week gestation period. Young moles grow rapidly and leave the nest to fend for themselves at about one month of age.

Nests are 4-16 inches below ground, usually in a protected area, like under a stump or a rock. Surface runways and deeper runways occur 3-12 inches below surface. The soil excavated from the deep tunnels is deposited on the surface through short vertical tunnels in volcano-like mounds.

It is worth mentioning that several people swear by various home remedies and frightening devices — and perhaps more of these “miracle cures” exist for moles than for any other pest. In the Purdue Extension publication, “Moles,” it says, “Desperate homeowners and gardeners have tried placing various materials irritating to moles in the runways. In general, these home remedies have no value in mole control.”

In fact, some can be hazardous to human health, other animals or detrimental to the environment.

For more information, ask your local Purdue Extension office for publication “ADM-10, Moles,” also available free online at: extension.entm.purdue.edu/publications/ADM-10.pdf.

John Woodmansee is extension educator in Noble and Whitley counties.

Leave a Reply

Your email address will not be published. Required fields are marked *