Chipmunks are commonly found in suburban and rural landscapes. While their quick movements are entertaining, their burrowing habits can become a frustrating nuisance. These small rodents can undermine sidewalks, patios, decks, and even the foundations of structures with their extensive tunnel systems. Implementing targeted control and exclusion strategies is necessary to manage a chipmunk problem and protect your property from structural damage.
Identifying Chipmunk Activity
Confirming that chipmunks are the source of yard damage is the first step, as their holes differ significantly from those made by moles or voles. A chipmunk burrow entrance is typically a small, neat, round hole, measuring between 1.5 to 3 inches in diameter. Unlike the volcano-shaped dirt mounds left by moles or the surface tunnels created by voles, chipmunk holes characteristically lack excavated soil around the opening.
The chipmunk achieves this clean look by carrying the displaced soil in its cheek pouches and scattering it away from the entrance to camouflage the burrow. These entrances are often hidden near structural features like foundation walls, retaining walls, steps, rock piles, or dense shrubbery. Below the surface, the burrow can become elaborate, extending up to 30 feet in length and 3 feet deep, creating nesting and food storage chambers. Damage is often seen as undermined pavement or the disappearance of flower bulbs.
Exclusion and Habitat Modification
Before resorting to physical removal, the environment should be made less inviting by eliminating attractants and installing physical barriers. Chipmunks are omnivores, and common food sources like fallen birdseed, outdoor pet food, and discarded nuts should be promptly removed or secured. Minimizing dense ground cover and piles of debris near structures also removes their preferred hiding places.
To physically block access, homeowners can install exclusion barriers made from durable materials like 1/4-inch hardware cloth around vulnerable areas. This wire mesh should be buried at least six inches deep and shaped into an L-footer extending outward to prevent digging under the barrier. For a non-lethal deterrent, chipmunks are known to avoid certain scents; granular repellents containing capsaicin or sprays based on peppermint oil or cider vinegar can be applied near burrow entrances and around plants.
Physical Removal Strategies
When habitat modification is insufficient, the most direct solution involves physical removal, typically through trapping. Live trapping is often preferred, using small, multi-catch or single-catch wire traps designed for rodents. Effective baits include a mix of peanut butter, sunflower seeds, or nuts.
Proper trap placement is inside the burrow’s travel path or directly next to the active entrance, ensuring the trap is stable and covered. If a chipmunk is successfully live-trapped, check local and state wildlife regulations regarding the relocation of nuisance wildlife. Many jurisdictions strictly prohibit or limit the distance for relocating wild animals, as releasing them nearby simply shifts the problem.
Lethal control is another option, often using snap traps positioned within a protective box or cover to prevent accidental harm. Specialized snap traps, similar to those used for rats, are effective when placed along known travel routes or at the mouth of the burrow. Consistent monitoring and immediate removal of captured animals is necessary for the process to be effective.
Repairing Damage and Preventing Re-entry
Once the chipmunks have been removed, the physical damage must be addressed to prevent re-colonization and structural compromise. The empty tunnels and holes should be properly filled to stabilize the soil, especially those near foundations or paved surfaces. Simply collapsing the holes with dirt is often ineffective, as the animals will easily dig them out again.
A more permanent solution involves filling the holes with a mixture of soil and small gravel, specifically a grade no larger than 1/4 inch in diameter. The gravel makes it harder for a chipmunk to re-excavate the area, discouraging future burrowing attempts. This material should be compacted firmly into the tunnel system to ensure stability. Ongoing site maintenance, including regular inspections of foundation barriers and continuous removal of food sources, will help ensure the yard remains chipmunk-free.