By Marcia Anderson
We hoped you learned about the differences between moles and voles in Part 1. Now that you know how to tell them apart, how do you discourage them from living in your yard and convince them to take up residence elsewhere?
To deter these landscape pests, be prepared to alter their environment. Preventing pest problems through foresight, is the #1 rule of Integrated Pest Management (IPM), which is beneficial to both your health and the environment. IPM is smart, sensible and sustainable – addressing the root causes of pest problems to provide a sustainable solution.
Regulating some of a mole’s food supply may help. Since moles are fond of beetle grubs in the lawn, you can begin by controlling the grubs. The three primary natural solutions are milky spore, beneficial nematodes and neem oil products. An annual lawn-grub treatment application of bacterial-based milky spore disease granules can definitely help, but it takes two-three years to become established in the soil and it doesn’t work in cold climates (colder than Zone 5).
Beneficial nematodes can be applied and will move through the soil to infect and kill the grubs. Neem has been used as an insecticide for centuries and acts as a repellent for grubs. However, as long as there are plenty of worms or ants in your lawn, you may still have a mole problem and may wish to resort to “Plan B.”
“Plan B” for moles utilizes their keen sense of smell that finds some plants offensive. You can use this knowledge as a natural way to control moles. Several bulb plants are known to repel moles such as daffodils, Siberian squill, and crown imperial, whose flowers give off a fox-like scent. Garlic, onions, leeks, chives, shallots and giant allium are living mole repellents as are the mole plant, or caper spurge and Mexican marigold.
Here are some helpful cultural controls you can use to prevent voles.
- Do not apply mulch too close to trees and shrubs. It provides voles with an easily tunneled, insulated pathway under snow, ice and frozen ground in the winter.
- Get rid of autumn leaves, twigs and debris that can make inviting pathways and remove ground cover that can hide voles. Bare soil makes them more vulnerable to predators.
- Place wire cages around individual plants: While impractical on a large-scale it is very effective for your favorite plants.
- Use ¼-inch hardware cloth or plastic cylinders to protect individual young trees and shrubs. Bury them slightly and extend at least two feet plus 18 inches above the snow depth to deter other gnawing pests
- Keep your garden weeded and avoid planting dense ground covers.
- Keep your lawn mowed short.
Castor oil is the most widely used mole and gopher repellent. Whether homemade treatment or a commercial product, it is made from ground-up corn cobs and castor oil. Other commercial vole repellents, are formulated with capsacian (the ingredient that makes peppers hot), repulsive smelling predator (coyote, fox or wolf) urine, or bitter testing chemicals. While these repellants are effective at keeping voles from eating live plants and bulbs, they need to be re-applied frequently because most dissipate with the rain. Voles may also become acclimated. Therefore, a varied approach works best with repellants. Fumigants, ultrasonic devices, and noise or vibration makers are not effective in repelling voles or moles.
Trapping moles or voles is an effective long-term control. Snap traps manufactured for mice are also effective at catching voles. Several EPA registered pesticides are also available for mole and vole control. Remember to read and follow the label directions on all pesticides carefully.
About the Author: About the Author: Marcia is with EPA’s Center of Expertise for School IPM in Dallas, Texas. She holds a PhD in Environmental Management from Montclair State University along with degrees in Biology, Environmental Design, Landscape Architecture, and Instruction and Curriculum. Marcia was formerly with the EPA Region 2 Pesticides Program and has been a professor of Earth and Environmental Studies, Geology, and Oceanography at several universities.