Groundhogs rarely attack people unprovoked, but they carry a surprisingly high risk of rabies for a rodent and their burrowing can cause real structural damage to foundations, decks, and outbuildings. Most homeowners who share a yard with a groundhog will never be bitten or harmed directly, yet the combination of disease risk and property undermining makes these stocky rodents worth taking seriously, especially when they settle close to buildings or gardens.
Groundhogs and Rabies
This is the most startling fact about groundhogs that most people do not know: among rodents and lagomorphs tested in the United States between 2011 and 2020, groundhogs accounted for more than 90 percent of confirmed rabies cases. Their rabies positivity rate was on par with high-risk species like bats and raccoons, and together with beavers, groundhogs made up 97 percent of all positive rodent and lagomorph cases during that decade.1PubMed Central. RABIES IN RODENTS AND LAGOMORPHS IN THE USA, 2011-20 That puts groundhogs in a different category from mice, squirrels, and rats, which almost never test positive for the virus.
Why are groundhogs so much more likely to carry rabies than other rodents? The answer has a lot to do with raccoons. Groundhog rabies trends closely track raccoon rabies trends, and the two species overlap heavily in the eastern United States.1PubMed Central. RABIES IN RODENTS AND LAGOMORPHS IN THE USA, 2011-20 A groundhog that encounters a rabid raccoon near a burrow entrance is large enough to survive the initial bite, pick up the virus, and go on to become rabid itself. Smaller rodents tend to be killed outright in such encounters.
For you, the practical takeaway is straightforward: if a groundhog approaches you, acts aggressively in broad daylight, seems disoriented, or is stumbling around, do not engage with it. That behavior is not normal for a groundhog, which is typically a shy, wary animal that bolts for its burrow the moment it spots a person. A groundhog behaving oddly should be reported to local animal control. If you or a pet are bitten by any groundhog, contact a physician or veterinarian immediately. Post-exposure rabies treatment is highly effective, but it needs to start quickly.
Bites and Defensive Behavior
Healthy groundhogs avoid confrontation. Their first instinct when startled is to whistle a sharp alarm call and dive underground. But corner one, try to grab it, or inadvertently block its escape route, and it will defend itself with the same large incisors it uses to gnaw through roots and bark. Groundhog bites can be deep, painful, and prone to infection simply because animal bites in general introduce bacteria into the wound.
Dogs are the most common domestic animal to tangle with groundhogs. A medium-sized dog that investigates a burrow entrance may find itself face to face with a groundhog that has nowhere to retreat. The resulting scuffle can leave both animals with bites and scratches. Keeping dogs leashed or supervised in areas with active burrows reduces this risk.
Children occasionally provoke encounters by trying to approach what looks like a cute, plump animal sitting in the grass. Teaching kids to observe from a distance and never attempt to touch or feed a wild groundhog is the simplest prevention. The animals are not aggressive by disposition, but they will use their teeth if they feel trapped.
Tick-Borne Disease Risks
Groundhogs serve as hosts for several tick species, including Ixodes cookei, sometimes called the groundhog tick. This tick is one of the known vectors for Powassan virus, a rare but serious arbovirus that can cause encephalitis in humans. Powassan virus is transmitted to small and medium-sized mammals by Ixodes ticks, and humans become infected through spillover from those natural transmission cycles.2Vector-Borne and Zoonotic Diseases. Powassan Virus: An Emerging Arbovirus of Public Health Concern in North America
Powassan virus infections remain uncommon compared to Lyme disease, but they are harder to treat and can be more severe. Unlike Lyme, which typically requires a tick to be attached for a day or more, Powassan virus can be transmitted in as little as 15 minutes of tick feeding. There is no specific antiviral therapy, so prevention matters most. Groundhog burrows near homes can concentrate ticks in areas where people and pets spend time, creating localized pockets of higher tick exposure in your yard.
Beyond Powassan virus, groundhogs can harbor fleas and other ectoparasites. While no one should panic about a groundhog living 50 yards from the house, a burrow right next to your patio or play area increases the chance that ticks drop off the animal and latch onto you, your children, or your pets.
Burrowing and Structural Damage
The most common property damage groundhogs cause has nothing to do with teeth. It comes from what they do best: dig. A single groundhog burrow system can extend 40 to 60 feet in length, with multiple entrances and chambers at depths of several feet. The excavated dirt often shows up as large mounds near entry holes, and the underground tunnels can undermine whatever sits above them.
Foundations are the biggest concern. A burrow that runs alongside or beneath a concrete slab, basement wall, or porch footing can cause settling, cracking, and water infiltration. The voids created underground allow water to pool and erode soil that was supporting the structure. Over months or years, this leads to visible damage: cracked foundation walls, uneven floors in the room above, or a porch that begins to sag. Repair costs vary widely depending on the extent of undermining, but even modest foundation work tends to run into the thousands of dollars.
Decks, sheds, and detached garages built on shallow footings are especially vulnerable. Groundhogs are drawn to the sheltered space underneath these structures, which offers overhead protection from predators. Once they establish a burrow beneath a shed, they may continue expanding it over multiple seasons, weakening the ground that the structure rests on. Homeowners sometimes discover the issue only when a support post sinks or a corner of the shed visibly drops.
Retaining walls, stone walls, and earthen embankments can also suffer. When groundhogs burrow into a slope that a retaining wall holds back, the result can be localized collapse. For properties with earthen dams or berms, the risk is even higher, since tunneling introduces pathways for water to seep through the structure.
In rural settings, groundhog holes in fields and pastures create a different kind of hazard. Livestock, horses especially, can step into burrow openings and suffer leg injuries. Farm equipment can drop a wheel into a hole and sustain damage or cause an accident. Farmers and ranchers in the eastern United States have dealt with this issue for generations.
Garden and Crop Damage
Groundhogs are herbivores with big appetites. An adult can eat more than a pound of vegetation a day during summer, and they have a particular fondness for the same crops gardeners plant: beans, peas, lettuce, broccoli, squash, and melons. A single groundhog can strip a small vegetable garden in a matter of days once it learns the food is there.
The damage extends beyond eating. Groundhogs clip plants at ground level, so even crops they nibble lightly may not recover. They also eat flowers, ornamental plants, and young fruit trees, gnawing bark at the base of trunks in a way that can girdle and kill a sapling.
On a larger agricultural scale, groundhogs are one of several wildlife species that collectively cause significant economic damage to crops. A study assessing wildlife depredation of agricultural crops in New Jersey documented close to $1.8 million worth of total crop damage from at least ten wildlife species, with groundhogs identified as one of the key offenders alongside deer and geese.3Journal of Extension. Assessment of Wildlife Depredation to Agricultural Crops in New Jersey For small farms and market gardens where margins are already thin, persistent groundhog pressure can mean the difference between a profitable season and a loss.
How to Tell If a Groundhog Has Moved In
Before you can manage the problem, you need to confirm you actually have a groundhog and not a rabbit, skunk, or some other burrowing animal. Groundhog burrows are distinctive: the main entrance is typically 10 to 12 inches in diameter, roughly the size of a dinner plate, and often has a large crescent-shaped mound of excavated dirt fanning out in front. Secondary “plunge holes” are smaller and usually lack the dirt pile because the animal digs them from underground outward as emergency escape routes.
Groundhogs are diurnal, meaning they are active during the day, with peak activity in early morning and late afternoon. If you see a chunky, low-slung animal waddling across the lawn around 7 a.m. and disappearing into a hole, that is almost certainly your culprit. They are surprisingly good climbers, too, capable of scaling a fence or tree when motivated.
Fresh digging around a burrow entrance, worn trails through the grass between the burrow and a food source, and nearby plants clipped cleanly at an angle are all signs of an active groundhog. In contrast, abandoned burrows often have cobwebs across the entrance, leaf litter filling the hole, or no fresh dirt.
Keeping Groundhogs Away from Your Property
The best defense is exclusion. Fencing a garden effectively against groundhogs requires burying the bottom edge at least a foot underground and bending it outward in an L-shape, because groundhogs will dig under a fence that simply meets the soil surface. The fence itself should be at least three to four feet tall, and some people add an electric wire along the top to discourage climbing.
For structures, closing off the space beneath decks, sheds, and porches with heavy-gauge hardware cloth or welded wire prevents groundhogs from setting up residence underneath. The mesh should be buried at least 12 inches deep and extend outward, just like garden fencing. If a groundhog is already living under the structure, sealing the entrances while the animal is inside will make the situation worse, as it will simply dig a new exit and may cause more damage in the process. The eviction needs to happen first.
Habitat modification helps too. Groundhogs prefer areas with tall grass, brush piles, and dense groundcover near their burrows because these provide concealment from predators. Clearing brush, mowing fields and lawn edges, and removing rock piles and wood stacks near buildings makes the area less attractive. A groundhog that feels exposed is more likely to relocate on its own.
Various commercial repellents exist, ranging from predator urine to castor-oil-based sprays. Effectiveness is mixed and usually temporary. Most wildlife professionals consider repellents a supplementary tool at best, not a standalone solution. Ultrasonic devices marketed for rodent control have little evidence supporting their use against groundhogs or any other wildlife.
Dealing with a Groundhog That Will Not Leave
When exclusion and habitat modification are not enough, the remaining options are live trapping and lethal control, both of which are regulated by state and local wildlife laws. In many states, you need a permit to trap and relocate wildlife, and some states prohibit relocation entirely because it can spread disease and dumps the animal in unfamiliar territory where its survival odds drop sharply. Check your state’s wildlife agency website before setting a trap.
Live traps baited with cantaloupe, apple slices, or fresh vegetables can be effective, but a trapped groundhog is a stressed and potentially dangerous animal. Wear heavy leather gloves if you need to handle the trap, and cover it with a cloth to calm the animal during transport. Better yet, hire a licensed wildlife control operator who has experience with groundhogs and knows the local regulations.
Fumigation of burrows with gas cartridges is another method used in rural areas, particularly where groundhog populations are damaging crops or endangering livestock. This should never be attempted near buildings, because the gas can seep through soil into basements, crawl spaces, or utility conduits. It is also illegal in some jurisdictions without a permit.
Groundhog Burrows and Other Wildlife
One nuance worth knowing is that groundhog burrows, for all the headaches they cause homeowners, play a meaningful ecological role. Abandoned burrows are used by a wide range of other animals, from foxes and skunks to rabbits, opossums, and even certain snake species. In suburban and urban landscapes where natural denning sites are scarce, groundhog burrows function as critical shelter for a whole community of creatures.
This creates a complicated dynamic for property owners. Filling in a groundhog burrow may solve one problem and create another, as the animals that were using the burrow for winter shelter scatter and may seek out other areas of your property. On the other hand, leaving a large active burrow system under your foundation is not an option either. The practical answer for most people is to allow burrows in areas where they do no structural harm, such as the far edge of a large yard, while aggressively excluding groundhogs from zones near buildings and gardens. This coexistence approach reduces conflict without eliminating the ecological benefits the burrows provide.
If you live in a suburban area with mature trees, patchy woodland edges, and neighbors who also have groundhogs, total elimination from the landscape is unlikely anyway. New groundhogs will move into vacated territories within a season or two. Long-term management is more realistic than eradication, and understanding the animal’s behavior makes that management more effective.