The small, striped chipmunk is a familiar sight in wooded and suburban landscapes across North America. These ground-dwelling rodents are often seen quickly moving across a yard, gathering nuts and seeds in their distinctive cheek pouches. While their presence might seem harmless, their extensive burrowing habits can present challenges for homeowners. Understanding these behaviors is the first step in determining if the chipmunk population constitutes a problem.
Identifying Chipmunk Activity in Your Yard
Confirming that chipmunks are the source of yard damage requires recognizing their specific signs, which are distinct from other burrowing pests like voles or shrews. Chipmunks are easily identified by their dark stripes and small size, typically measuring between 5 to 6 inches long. They are diurnal, meaning they are active during the day, which makes them visible while they forage and dig.
The most telling sign of chipmunk activity is the entrance to their burrow system. These holes are typically small and neat, about two inches in diameter, or roughly the size of a silver dollar. Chipmunk burrows usually lack the mound of excavated dirt common with gophers or moles, because they carry the soil away in their cheek pouches and scatter it.
These clean entrances are often hidden beneath objects like steps, rock walls, wood piles, or dense shrubbery. If you observe a small, neat hole, especially one located near a structure, it is likely a chipmunk burrow. Their foraging is indicated by quick movements and the frequent sight of them stuffing their pouches with seeds, nuts, or fallen birdseed.
Structural and Landscape Damage Caused by Chipmunks
The negative impact of chipmunks falls into two categories: damage to landscaping and concerns regarding hardscapes and structures. In the garden, chipmunks consume flower bulbs, seeds, and tender seedlings, ruining newly planted areas. Their constant digging while searching for food or creating new burrows can disturb mulch beds and uproot young plants.
A significant concern arises when burrows are situated near man-made structures. Chipmunks prefer to dig next to objects that offer cover and stability, often excavating soil underneath patios, concrete steps, retaining walls, and foundation slabs. This soil displacement and void creation can compromise the stability of these hardscapes. The undermining of soil can lead to settling, cracking, or the eventual collapse of a retaining wall or porch.
Secondary issues stem from their feeding habits, especially their attraction to bird feeders. Chipmunks raid feeders, causing seed to spill onto the ground, which attracts other pests like mice and rats. They can also carry parasites such as fleas and ticks, which are a concern for pets and humans. Homeowners should treat burrowing near structural supports with seriousness, as this represents the most destructive potential of chipmunk activity.
Practical Strategies for Mitigation
Addressing a chipmunk problem focuses on making the environment less appealing by limiting food and shelter. Habitat modification involves removing potential hiding places near the home and garden perimeter. This includes clearing away accumulated wood piles, rock stacks, and dense brush that provides cover for burrow entrances.
Securing food sources is paramount to encouraging them to move elsewhere. Bird feeders should be modified with baffles or equipped with trays to catch spilled seed, preventing easy access to food on the ground. Storing pet food, grass seed, and bird seed indoors in rodent-proof containers eliminates another major attractant.
For preventing damage to vulnerable areas, exclusion methods are the most reliable long-term solution. Buried barriers, such as L-shaped wire mesh footers or hardware cloth with a quarter-inch mesh, can be installed around the base of decks, sheds, or foundation gaps to prevent tunneling underneath. Flower bulbs can be protected by planting them beneath a layer of quarter-inch hardware cloth, which allows the plant to grow through while blocking access. Commercial repellents containing capsaicin or predator urine are available, but they often require frequent reapplication and offer only temporary deterrence compared to physical exclusion.