Woodchucks

Young woodchucks are known as chucklings, but you won’t be laughing if they find their way into your garden or lawn.

Groundhog (Cephas) CC BY-SA 3.0

Woodchucks (Marmota monax) are also known as groundhogs, chucks, whistlepigs, and land beavers. These are large rodents related to a subgroup of ground squirrels known as marmots. Their name means digger. And dig they do.

Unlike other marmots, which prefer rocky, mountainous terrain, woodchucks are creatures of lowland soil and forest edges. Just as their distant cousin the beaver engineers and alters waterways, woodchucks are essential to maintaining healthy soil in the plains and woodland habitats. Native to Alaska, Canada, and the Eastern United States, there’s no telling how future populations may spread in response to our changing climate.

Woodchuck description

As a member of the squirrel family (Sciuridae), groundhogs tend to be grayish-brown, but with stubby tails. They have large incisors that grow (and are worn down) at a rate of about one-sixteenth of an inch each week. Adults can be two feet long, and their weight fluctuates seasonally, ranging from 6 to more than 11 pounds. They have short, powerful legs and long claws that help them burrow and climb trees. They can also swim.

Groundhog displaying its incisors (Mousebelt) CC BY-SA 4.0

Woodchucks are extremely intelligent, independent creatures that tend to be aggressive. They live in groups, called aggregations, and they whistle warnings and help each other burrow. After mating, a breeding pair will stay in the same underground chamber until the mother gives birth. Then the dad leaves until the young are weaned. Litters average three to five pups, though there can be as many as nine.

It’s unlikely you will ever see a groundhog because they hibernate in winter and spend much of the rest of the year underground or close to a burrow entrance. They are diurnal, which means they are most active at dawn and dusk. Captive woodchucks may live up to 14 years, while their wild siblings average only 2 or 3 years. A lucky few can survive up to six years, but badgers, bobcats, cougars, coyotes, dogs, gray wolves, and red foxes make short work of many adult groundhogs. Chucklings are often prey to cats, mink, raptors, and rattlesnakes. In some regions of the U.S., groundhogs are hunted for food, fur, and sport. [Why people consider hunting for sport humane in this day and age I’ll never understand.] Luckily for woodchucks, human development has provided a boon by reducing the number of predators while increasing their food supply. And therein lies the problem for gardeners.

A motionless individual will whistle when alarmed, to warn other groundhogs. (Marumari) CC BY-SA 3.0

Woodchuck burrows

The average woodchuck burrow has a six- to eight-inch opening and results in the removal of as much as six cubic feet of earth. This is good for the soil. No, it’s great for the soil. Woodchuck burrows aerate the soil, bring up subsoil and occasional artifacts, improve drainage, and aid in nutrient mixing without seriously damaging microbial networks. Their burrowing provides habitat for arthropods, increasing biodiversity. Those are all good things, but those burrows are big. And they can destroy a lawn or garden practically overnight.

Burrows can be more than 20 feet long, with small side rooms for sleeping, raising young, and pooping. Yes, groundhogs make and use bathrooms. In one study, a 24-foot burrow resulted in 640 pounds of soil being moved by two-foot rodents. Those tunnels can be three feet deep and have two to five entrances. These burrows can end up under your house, damaging its foundation. Of course, that would take a long time and several woodchucks, but it is possible.

Woodchuck diet

Woodchucks are mostly herbivores. I say mostly because they will also eat baby birds, grasshoppers, grubs, and snails on rare occasions. They prefer wild grasses, berries, and crops (your garden). In their preparation for winter, these garden mammals can eat up to a pound of plant material each day. And they love apples, beans, broccoli, cabbage, carrots, corn, lettuces, melons, peas, and soybeans. Since they live in large groups, this can mean trouble for farmers and gardeners.

Groundhog management

If groundhogs appear in your landscape each year, the first thing you can do is reduce the number of aboveground hiding places. This means piles of rocks, wood, or soil have to go. Many sources recommend fencing as a way to thwart groundhogs but, unless your fence goes three or more feet deep, they will still get in. You may need to cage your favorite plants. This is much easier with raised beds, but it does mean installing hardware cloth bottoms before adding soil and plants. Beyond that, there are lethal and nonlethal methods of controlling groundhogs.

Depending on where you live, you may choose to shoot them. Unless you are sure a lethal trap will kill instantly, I do not recommend that method. Fumigation is another option, but I am not sure about its effectiveness or humanity.

Since groundhogs are prey animals, installing scare tactics may work for a while. Like us, these creatures can get used to pretty much anything. Motion-sensing sprinklers, flashing lights, and noise-makers may chase away your local woodchucks for a while, but if they want what you’re growing, they’ll be back. And forget the ultrasonic repellers. They don’t work.

Live-trapping is an option, but only if you have the time, patience, and equipment. Or, you may want to invest in a professional for this task. They know what they’re doing and can relocate trapped groundhogs to a better location (far from your garden). Or learn to live with them if you can.

​Punxsutawney Phil

We couldn’t very well discuss groundhogs without mentioning the most famous one of all, Punxsutawney Phil. According to local tradition, a Pennsylvania resident groundhog predicts either six more weeks of winter or early spring every February 2nd, depending on whether or not he casts a shadow. This year, the prediction is for more winter. 

Punxsutawney Phil being held by a member of the Inner Circle in 2018 (Chris Flook) CC BY-SA 4.0

Don’t worry, though. It ends up that groundhogs aren’t very good at predicting the weather. Since the tradition began in 1887, it’s only been accurate 39% of the time.

Now you know.