Groundhogs, also known as woodchucks, quickly turn a backyard or garden into an excavation site with large, disruptive burrows. These rodents are notorious for the extensive damage their tunneling causes to lawns, foundations, and vegetable patches. Homeowners often seek fast-acting solutions to deter this persistent pest, and the use of strong-smelling substances like ammonia is a common DIY approach.
The Use and Limitations of Ammonia as a Deterrent
Ammonia is used as a groundhog deterrent because its potent, acrid odor mimics the smell of predator urine, such as that from a fox or coyote. The strong scent is intended to create an irritating environment near the burrow entrance, suggesting danger to the residing animal. A typical application involves soaking rags with concentrated ammonia and placing them directly into the primary entrance hole of the burrow system.
While this method might cause an initial disturbance, its effectiveness is minimal and highly temporary. Ammonia is volatile and evaporates rapidly, meaning the repelling scent quickly dissipates in an open-air environment. Groundhogs often wait for the smell to fade or, more commonly, dig a new exit hole a short distance away from the treated area.
Using concentrated ammonia also introduces safety concerns for both humans and pets. The fumes are toxic and can be highly irritating to the eyes, nose, and respiratory system. Placing chemical-soaked materials directly into the soil risks contaminating the immediate area, posing a health hazard to non-target animals or children. Professional wildlife experts advise against relying on ammonia as a primary or long-term solution for groundhog control.
Active Eviction and Humane Removal Methods
For an active groundhog problem, effective solutions focus on humane removal and eviction rather than temporary deterrents. Live trapping is the most reliable method for removing a groundhog from a property. The ideal trap is a sturdy, wire mesh cage, typically sized for raccoons or woodchucks, and it should be placed directly in the travel path leading to the burrow entrance.
Baiting the trap with fresh produce that groundhogs favor significantly increases the chance of a successful capture. Baits should be placed toward the rear of the trap to ensure the animal fully enters and triggers the closing mechanism. It is imperative to wear gloves when handling the trap and bait to prevent the transfer of human scent. Highly effective baits include:
- Cantaloupe
- Pieces of apple
- Fresh lettuce
- Carrots
Before attempting relocation, consult local and state regulations, as the law often restricts where and how captured wildlife can be released. Alternative eviction methods focus on creating a consistent, low-level disturbance to encourage the groundhog to leave on its own. This can involve placing a radio tuned to a talk station near the burrow entrance or applying commercial repellents that feature castor oil, which groundhogs find highly offensive. These actions are designed to make the burrow feel insecure, prompting the woodchuck to relocate without requiring physical capture.
Permanent Physical Exclusion Measures
The long-term solution for groundhog control is physical exclusion, which involves modifying the environment to make the area inaccessible for burrowing. Standard fences will not deter a determined groundhog, as they are skilled diggers and climbers, necessitating a specialized barrier design. The most effective method is the construction of an “L-foot” barrier using heavy-gauge, galvanized wire mesh with openings no larger than two inches.
This barrier must be sunk into the ground a minimum of 10 to 12 inches deep to prevent tunneling underneath the fence line. The defining feature is the bottom section of the mesh, which is bent outward at a 90-degree angle, extending horizontally away from the protected area for another six to twelve inches. When the groundhog attempts to dig at the fence base, it immediately encounters this horizontal wire apron, which acts as a false floor and frustrates its digging efforts.
It is also important to seal off access points under structures such as sheds, porches, and decks, as these areas provide ideal, sheltered locations for burrow establishment. After confirming the groundhog has been successfully evicted, all openings must be secured with the same heavy-duty wire mesh or concrete. The wire mesh should be extended into the soil in the L-foot configuration to ensure the groundhog cannot re-dig a new entry point next to the sealed opening.