There are many ways to control chipmunks -- from prevention to trapping to homemade chipmunk repellents. In fact, because chipmunks are rodents, many of the same methods can be used for to control chipmunks as those used to get rid of rats, mice, and squirrels. But the most humane ways are prevention and exclusion.
1. Prevent and Exclude Chipmunks
The Humane Society recommends making changes to your yard to reduce chipmunk damage and presence -- without having to trap them.
- Place L-shaped footers around the home's foundation as well as any foundations, sidewalks, porches, and retaining walls to keep chipmunks from burrowing.
- Remove wood or rock piles and trim back plantings; these provide cover or food for chipmunks.
- Surround the yard or home with a plant-free gravel border.
- To keep chipmunks from digging up flower bulbs, plant them beneath a wire or plastic screen ground cover or in bulb cages. Mesh of 1 x 1 inch will be large enough to allow plants to sprout but small enough to stop the chipmunk digging.
- Plant only bulbs to which wildlife is not attracted, such as daffodils (Narcissus) or Allium.
Other rodent- or pest-proofing techniques that will also help control chipmunks include:
- Placing ¼-inch mesh hardware cloth around gardens and flowers.
- Keep firewood and other such piles away from the home to keep chipmunks from burrowing beneath the pile … and then under the home’s foundation.
- Do not allow trees, shrubs, or other plantings to run continuously from wooded areas to the home, as this will draw chipmunks in.
- Do not keep food items outdoors, including pet foods and bird seed, unless it is placed in rodent-proof containers.
2. Chipmunk Repellents
There are no repellents specifically registered for use against chipmunks, and the use of repellents is somewhat controversial.
Although Missouri Department of Conservation advises that fumigants and repellents “are not recommended because none are known to be effective," the Humane Society states that “commercial repellents that promise to repel squirrels will also repel chipmunks.” Some squirrel repellents include:
- Thiram applied to plant bulbs, stems or bark.
- Moth balls or flakes (Naphthalene) placed around gardens.
- Commercial products containing thiram, bitrex, nicotine sulfate, methyl nonyl ketone crystals and polybutene applied to plants that are not to be eaten by humans. Applications may need to be repeated because rain and watering can wash them away.
- To make a homemade chipmunk repellent, mix together:
- 1 tsp of Lysol
- 3 ounces Epsom salt
- 1 gallon water
3. How to Trap a Chipmunk
Because of the debate over the effectiveness of repellents for chipmunks, trapping is often considered to be the most practical and effective way to rid of chipmunks.
- Use wire mesh, box, or rat snap traps.
- Place traps perpendicular to the route the chipmunk follows. For best results, place two traps in the pathway back to back (with the trigger of each facing away from the other).
- Good chipmunk baits are peanut butter, nuts, meat, pumpkin seeds, sunflower seeds, raisins, and cereal grains.
- For the first few days, bait the traps but do not set them to condition the chipmunk to take the bait. After two or three days bait and set the trap.
- Be sure to place traps in areas where they will not be contacted by children, pets, or other non-target wildlife. For greatest safety, place the trap into or beneath a small box that has holes only large enough for the chipmunk to enter. To increase attraction, place some bait at the entrance to the box as well as in the trap.
4. Keep Chipmunks Out of Bird Feeders
Chipmunks are ground feeders, so they are attracted to the spilled seed of bird feeders. So, to keep chipmunks away from bird feeders:
- Regularly clean up spilled seed.
- Choose seed to which chipmunks (and squirrels) are not attracted, such as thistle.
- Place bird feeders at least 15 to 30 feet away from any structure.