Chipmunks are very common throughout most of Wisconsin in wooded and semi-wooded areas. Chipmunks are 8 to 10 inches long from head to tail and have dark and light stripes on their backs. People sometimes confuse chipmunks with 13-lined ground squirrels. Ground squirrels have longer bodies, shorter lighter-colored hair, and many more stripes on their backs. Also, they live in open, grassy areas, not wooded areas. You can tell the difference between the two animals when they run. Chipmunks hold their tails up while running, but ground squirrels do not.
Although chipmunks feed on nuts, seeds, berries, and sometimes flower buds, they do little direct damage to garden and landscape plants. They may disturb small seedlings and transplants while foraging for food and may occasionally make a burrow right beneath a plant, causing the soil to dry out faster in the plant’s root zone.
Active during the day, chipmunks are quite visible, so people blame them for many plant problems they do not cause. Instead, rabbits, groundhogs, 13-lined ground squirrels, or meadow mice are usually the culprits when you see extensive animal damage to plants.
Although chipmunks do little damage to plants, they can cause significant problems in rock gardens and walls, and they frequently invade garages and storage buildings in search of food and shelter. You can usually leave them alone. Building problems can usually be solved by closing doors, sealing access points, and removing or securing stored bird seed or pet food.
However, if you wish to eliminate chipmunks, cage trapping is your best option. Cage trap them with a small box trap, and release them in a wooded area with permission of the landowner. If you are not inclined toward relocation, a rat-sized snap trap is also very effective. Place rat-sized snap traps inside of boxes with 2-inch holes cut on the side to prevent the capture of birds who may be attracted to the seeds when they fly overhead. Keep snap traps out of reach of pets and children. Good baits for trapping chipmunks include sunflower seeds and nut meats.
If you have a high chipmunk population, you may have to trap many individuals before you solve the problem. Chipmunks hibernate and are not to blame for rodent problems experienced during the winter. Look for rats, mice, tree squirrels, or other potential pests during cold weather.