Voles are small, stocky rodents that inflict substantial damage on lawns and gardens. Often called meadow mice, these herbivores primarily feed on plant material, destroying roots, bulbs, and seeds. They are notorious for girdling—gnawing the bark off young trees and shrubs—which can kill plants during winter. Because voles reproduce rapidly, infestations escalate quickly, requiring prompt control measures. This article details methods for confirming an infestation, eradication, and long-term management of voles.
Confirming the Pest: Vole Identification and Damage Assessment
Identifying the pest is necessary, as control methods for voles, moles, and shrews differ. Voles have short tails, small eyes, and blunt snouts, resembling a stocky mouse. The most definitive sign of activity is surface runways—narrow, well-worn paths one to two inches wide in the grass or under cover like mulch.
Unlike moles, which create volcano-shaped soil mounds, voles create small, open burrow entrance holes near food sources or dense vegetation. Their feeding damage is distinct, leaving irregular gnaw marks on tree bark low to the ground. Visible surface trails or damage to bulbs eaten from below confirm a vole infestation.
Mechanical Eradication: Effective Trapping Strategies
Mechanical trapping is an effective method for killing voles, especially in smaller areas. Standard mouse-sized snap traps or specialized vole traps are successful and should be deployed in high numbers due to rapid reproduction; a small area may require ten or more traps.
Traps must be placed strategically within active surface runways, set perpendicular to the path of travel so the vole crosses the trigger plate. Effective baits include apple slices, peanut butter mixed with oatmeal, or seeds, secured onto the trigger. Cover the set traps with a board or inverted bucket, ensuring a small opening for entry. Check traps twice daily and continue re-baiting until no new voles are caught for several days.
Chemical Control: Using Baits and Rodenticides Safely
For large or persistent infestations, chemical control using rodenticides can be considered, but strict safety precautions are mandatory. Vole baits contain active ingredients like zinc phosphide (a single-dose toxicant) or anticoagulant compounds such as warfarin. While anticoagulants require multiple feedings, they are effective and widely registered for vole control.
All rodenticides must be placed inside tamper-resistant bait stations to protect children, pets, and non-target wildlife from accidental exposure. Place these stations near known vole activity, such as runway entrances, and away from competing food sources. Secondary poisoning is a concern, especially with anticoagulants, as predators like hawks or scavenging animals may consume affected voles. To mitigate this risk, regularly search for and safely dispose of any poisoned vole carcasses.
Long-Term Management and Exclusion
Once the immediate population is controlled, long-term management focuses on making the environment less hospitable and excluding voles from valuable plants. Voles thrive in areas with dense ground cover, making cultural modifications effective deterrents. Keeping grass closely mowed and removing heavy layers of mulch, weeds, and debris eliminates the protective cover used for traveling and nesting.
Physical exclusion provides robust protection for individual trees and garden beds. Cylinders made from galvanized hardware cloth (one-quarter inch mesh or less) can be installed around the base of young trees and shrubs. For effective exclusion, the barrier must be buried at least six inches deep, with a portion bent outward to form an L-shape to deter burrowing. The above-ground cylinder must extend higher than the maximum winter snow line to prevent voles from accessing the bark beneath the snow.