Burrowing animals quickly turn well-maintained lawns and gardens into landscapes marred by tunnels and mounds. These subterranean inhabitants are typically motivated by the search for food and the need for secure shelter. Effective management requires correctly identifying the culprit, as control methods vary significantly based on the animal’s biology and behavior. Addressing the problem involves modifying the environment to make it less appealing and implementing physical or direct interventions.
Identifying the Burrowing Culprit
Correctly identifying the animal creating the damage is the first step toward successful control. The three most common yard intruders—moles, gophers, and voles—each leave distinct physical evidence and have different diets.
Moles are insectivores, not rodents, and their damage results from searching for food like earthworms and grubs. They create two primary types of disturbance: volcano-shaped mounds with soil pushed up from the center, and raised, spongy surface runways that feel soft when stepped upon. These shallow feeding tunnels are often used repeatedly as the mole hunts for prey.
Gophers are true rodents and herbivores that feed on plant roots and vegetation. Their burrow systems are characterized by fan-shaped or crescent-shaped mounds of soil, where the entrance hole is typically plugged. Gopher tunnels are generally deeper and larger than mole tunnels. Their damage to plants comes from below ground as they consume roots, bulbs, and tubers.
Voles, sometimes called meadow mice, are small rodents that primarily eat stems, bark, and roots near the surface. They rarely create large mounds. Instead, they leave small, open burrow holes and distinct, visible surface runways through the grass, which look like well-worn trails of dead or clipped vegetation. Their presence is often confirmed by gnawed plants, especially near the ground level.
Making Your Yard Unappealing (Cultural Control)
Modifying the habitat to reduce its attractiveness is a preventative, non-invasive method that discourages burrowing animals from settling. This strategy focuses on eliminating the primary resources—food and shelter—that draw the animals to the property.
Reducing Food Sources
Reducing the population of insects and grubs in the soil directly targets the mole’s main food source. Homeowners can apply beneficial nematodes or milky spore disease (biological controls for grubs), or use targeted chemical treatments. When the food supply diminishes, moles are less likely to establish extensive tunnel systems and will move elsewhere to hunt.
Managing Water and Soil
Over-watering a lawn can inadvertently invite burrowing activity by softening the soil, making it easier for animals to dig. Excess moisture also promotes a higher population of earthworms and insects, further encouraging moles. Adjusting irrigation schedules to water less frequently but more deeply helps maintain firmer soil and reduces the abundance of a mole’s preferred prey.
Removing Cover
Removing dense ground cover, debris, and low-lying brush piles eliminates safe harborage for animals like voles and groundhogs. These piles offer concealed shelter and protection from predators. Maintaining a clean, open yard reduces the available cover, making the area less hospitable for long-term residency.
Installing Physical Barriers and Exclusion
Physical barriers offer the most reliable, long-term solution for protecting specific areas of the yard from burrowing activity. These methods create an impenetrable underground defense that prevents animals from digging past a certain point.
Installing Below-Ground Barriers
To protect vulnerable areas like garden beds or shed perimeters, install a below-ground barrier using galvanized hardware cloth or welded wire mesh. This material should be buried at least 18 to 24 inches deep vertically into a trench, as many burrowers can dig surprisingly deep. For maximum effectiveness against persistent diggers like gophers, the bottom of the mesh should be bent outward at a 90-degree angle. This creates a horizontal “L-footer” that extends 6 to 12 inches away from the protected area.
The L-footer design forces any animal attempting to dig under the barrier to encounter the wire mesh horizontally, deterring further excavation. Mesh size is also important. For most small burrowing rodents, a mesh opening of \(1/4\) inch or \(1/2\) inch is recommended to ensure they cannot squeeze through. While a 1-inch by 1-inch mesh may suffice for larger animals like groundhogs, finer mesh is necessary for voles and small rodents.
Protecting Individual Plants
Protecting individual plants, especially new plantings or high-value shrubs, can be accomplished using wire mesh baskets, often called gopher baskets. These baskets are placed around the root ball before planting, creating a permanent cage that allows roots to grow while blocking gophers and voles from feeding. The top edge of the basket should remain slightly above the soil surface to prevent voles from accessing the plant stem or bark.
Foundation Barriers
Foundation barriers deter animals seeking shelter under structures like decks, porches, and sheds. Seal all openings with heavy-gauge wire mesh, securely fastened to the structure and buried deep with an L-footer, to prevent entry. Before completing the seal, monitor the area for several days to ensure no animals are trapped inside, which creates a complicated problem.
Direct Action: Trapping and Repellents
Active intervention, utilizing traps and repellents, is typically reserved for situations where prevention and exclusion methods have failed or are impractical. These actions aim to remove established animals or immediately deter them from their current location.
Chemical Repellents
Chemical repellents work by appealing to the animal’s sense of taste or smell, making the area undesirable. Products containing castor oil are commonly used, as this substance is believed to be offensive to moles and gophers. However, its long-term efficacy is inconsistent and requires reapplication. Predator urine scents may deter some species, but hungry animals often show less sensitivity to these deterrents.
Sonic Devices
Sonic or vibration devices are another repellent category, consisting of stakes placed in the ground that emit periodic vibrations or sounds. The principle is that these disturbances drive subterranean animals away. Scientific evidence confirming their effectiveness across different species and soil types is limited. These methods should not be relied upon as the sole solution for a severe infestation.
Trapping
Trapping is considered one of the most effective methods for controlling established populations of burrowing animals, particularly gophers and moles. For gophers, lethal traps like cinch traps or box-type traps are set directly into the main tunnel runway, requiring location of the active burrow system. Mole traps, such as scissor or harpoon types, are similarly placed in active surface runways.
Before deploying any trap or using chemical controls like fumigants or poisons, check local municipal and state regulations. The use of lethal traps, certain chemical baits (like strychnine or zinc phosphide), and the live release of captured animals are all subject to varying legal restrictions. Strict adherence to product instructions and safety guidelines is necessary to prevent harm to non-target animals, pets, and humans.