A mole is a small, subterranean insectivore, a mammal built for tunneling, not a rodent. These creatures live almost entirely underground, constantly digging to find food. This perpetual foraging results in visible damage that frustrates homeowners: unsightly soil mounds and raised ridges across the lawn. Moles excavate extensive networks of tunnels to hunt, creating a widespread disturbance that demands a focused strategy for resolution.
Identifying the Culprit and Damage
Correctly identifying the damage is crucial, as moles are often confused with other yard pests. Mole activity is characterized by two distinct disruptions: the volcano-shaped molehill and the raised surface run. The molehill is a symmetrical, conical mound of loose soil pushed up from a deep main tunnel, which serves as the animal’s primary travel route.
Surface runways appear as spongy, raised ridges across the turf. These are temporary tunnels created just beneath the grass roots as the mole forages for food. This pattern differentiates mole damage from that caused by voles, which leave small, open holes and primarily eat plant roots. Shrews, also insectivores, do not create extensive tunnel systems.
Effective Methods for Physical Removal
Trapping is the most consistently reliable method for mole removal, offering a permanent solution. Success depends on locating and setting a trap directly within an active, main runway, as surface feeding tunnels are often abandoned quickly. To determine activity, gently flatten a short section of the raised runway. If the tunnel is pushed back up within 12 to 24 hours, it is a primary, frequently used passage.
Once an active main run is confirmed, the trap must be precisely set to intercept the traveling mole. There are three effective types of traps: the scissor-jaw, the harpoon (or plunger), and the choker loop. Scissor traps use spring-loaded loops that clamp shut when triggered. Harpoon traps drive spikes downward into the tunnel, while choker loop traps use a wire loop to snare the mole as it passes.
The trap should be placed directly into the main tunnel, often requiring a small section of turf to be removed to expose the run. For choker loop or scissor traps, the mechanism is set deep enough so the trigger plate is directly in the mole’s path. Backfill the exposed area with loose soil or cover it with a board to block out light and air, as moles are highly sensitive to disturbances and may avoid an open tunnel. Traps must be handled with care and kept away from children and pets.
Non-Invasive Deterrents and Landscape Adjustments
Non-invasive strategies are designed to make the environment less hospitable to the mole. Castor oil-based products are a common deterrent, creating an irritating scent and taste that moles find repulsive. These commercial repellents contain ricinoleic acid and are typically mixed with water and a surfactant to help the oil penetrate the soil profile. The goal is to saturate the area, driving the mole to relocate away from the treated section of the yard.
The use of sonic or vibratory devices inserted into the ground is another option, though less consistently effective. These battery or solar-powered spikes emit pulses intended to disrupt the mole’s sensitive ability to navigate and locate prey. Moles are known to acclimate to constant, repetitive sounds, and the effectiveness of these devices varies greatly depending on soil type and moisture content.
A foundational approach involves eliminating the mole’s primary food source, which consists mainly of earthworms, grubs, and other insect larvae. Moles have a high metabolism, so reducing their food supply can cause them to move to a richer hunting ground. While applying a biological control like Milky Spore powder targets Japanese beetle grubs, it will not eliminate the earthworms that make up the largest portion of a mole’s diet. Using insecticides to control the entire subterranean insect population is a broader approach, though it requires careful timing to avoid harming beneficial soil organisms.