You can identify most burrowing animals by looking at three things: the diameter of the hole, the shape and presence of a dirt mound, and where the hole is located. A 1-inch hole in your lawn points to a very different animal than an 8-inch opening next to your shed. Once you know what to look for, narrowing down the culprit is straightforward.
Small Holes: Under 2 Inches
The smallest holes in your yard, around 1 inch in diameter, typically belong to voles. These mouse-like rodents create small openings to reach tubers and bulbs underground. The easiest giveaway is their surface runways: narrow, criss-crossing trails worn into the grass, most visible in early spring after snow melts. You may also spot larger patches of dried grass nearby where voles store food and nesting materials.
Chipmunk holes are slightly larger, about 2 inches in diameter, roughly the size of a quarter. What makes them distinctive is what you won’t see: there’s almost never a dirt mound around the entrance. Chipmunks carry excavated soil in their cheek pouches and scatter it away from the burrow, keeping the opening clean and inconspicuous. If you find a small, tidy hole with no soil pile at the base, a chipmunk is the likely resident.
Medium Holes: 2 to 4 Inches
Norway rats dig burrows with openings 2 to 4 inches in diameter. The entrance is typically smooth and well-worn from repeated use. Location is the strongest clue here. Rat burrows cluster along foundations, walls, sidewalk edges, and under structures like porches, decks, and sheds. They favor sandy soil, concealed spots near food and water, and areas with dense vegetation like bushes or garden beds. If you find a smooth, medium-sized hole tucked against your house or garage, rats are the most likely explanation.
Large Holes: 6 Inches and Up
Woodchuck (groundhog) dens average about 8 inches wide and are often found near structures like sheds, garages, and porches. The signature feature is a “dirt porch,” a heap of loose soil and sometimes rocks fanned out in front of the main entrance. Woodchucks avoid wet soils, so their dens tend to appear in well-drained areas. Not every den has two openings, but the primary entrance with its prominent soil pile is hard to miss.
Badger holes are similarly large, over 6 inches wide, but they show up in different territory. Badgers dig where their prey lives, so their holes tend to appear in areas with pocket gopher or ground squirrel activity. If you’re finding a big hole in an open field or grassland rather than next to a building, a badger is more likely than a woodchuck.
Mounds Without Visible Holes
Sometimes the problem isn’t a hole at all but a mound of dirt with no obvious opening. This usually means moles or pocket gophers, and the mound shape tells you which one.
Mole mounds are volcano-shaped with a circular margin. The soil pushes straight up from below, creating a symmetrical cone. Moles also leave raised, winding ridges just below the lawn surface from their shallow foraging tunnels. You can push these trails flat by stepping on them. In warmer weather, some mole species work 6 inches or deeper below the surface, so you may see mounds without obvious surface trails.
Pocket gopher mounds are crescent-shaped or fan-shaped, with a plugged burrow opening visible on one side. The asymmetry is the key distinction: instead of a round volcano, you’ll see soil pushed to one side with a sealed dirt plug where the tunnel meets the surface. If you’re staring at a mound and can’t decide, look at the margin. Circular means mole. Crescent with a plug means gopher.
Shallow Foraging Holes
Not every hole is a burrow. Skunks and raccoons dig shallow, temporary holes while hunting for grubs and insects, and these look quite different from permanent dens.
Skunk foraging holes are small, roughly the width of a skunk’s nose, and surrounded by a ring of loosened soil. They’re shallow and scattered across your lawn, created as the skunk digs for earthworms, grubs, and beetles. You’ll often find a cluster of these holes appearing overnight.
Raccoons leave a messier scene. Rather than poking neat holes, they use their front paws to pull up and flip pieces of sod, leaving torn or rolled-back patches of turf. If your lawn looks like someone peeled sections of it away, raccoons are the more likely culprit. Both animals are after the same food (grubs and soil insects), but their methods are visibly different.
Insect Holes in the Ground
Ground-nesting insects can produce holes that look surprisingly animal-like. Cicada killer wasps dig burrows about 1.5 inches in diameter in well-drained, light-textured soil, preferring areas with full sunlight. Each tunnel extends 12 to 18 inches at an angle and reaches about 6 to 10 inches deep. A large nesting group creates conspicuous mounds of displaced soil that can make a lawn look heavily disturbed. Despite the intimidating size of these wasps, they’re solitary and rarely sting. If you’re seeing inch-and-a-half holes with small dirt mounds in a sunny, sandy patch of your yard during summer, insects are likely responsible rather than rodents.
Mud Chimneys in Wet Areas
If you find small, smokestack-shaped towers of mud pellets in a soggy part of your yard, you’re looking at crayfish chimneys. Burrowing crayfish build these structures in areas where water saturates the ground. They roll excavated mud into small pellets, carry them to the surface, and stack them into a chimney around the tunnel opening. One interesting detail: the chimney may show bands of different colors, reflecting the different soil layers the crayfish tunneled through. These are harmless and only appear in consistently wet ground.
Holes That Snakes Use
Snakes don’t dig their own burrows. They occupy holes originally made by rodents and other small animals, so a “snake hole” looks identical to a chipmunk or vole hole. To determine whether a snake has moved in, look for freshly shed skin near the opening or snake droppings, which are tubular, dark, and often streaked with white, chalky urine. You may also see bone fragments or fur in the droppings. If the hole has spiderwebs or accumulated debris across the entrance, it’s probably vacant.
Putting the Clues Together
When you find a mystery hole, work through three questions in order. First, measure the opening. Under 2 inches points to voles, chipmunks, or insects. Two to 4 inches suggests rats. Six inches or larger means woodchucks or badgers. Second, check for a mound. A crescent-shaped mound with a plug means pocket gopher. A volcanic mound means mole. A large dirt porch means woodchuck. No mound at all suggests chipmunk. Third, note the location. Next to a foundation or under a structure suggests rats or woodchucks. Open sunny ground points to badgers or cicada killers. Wet, saturated soil means crayfish. A network of surface trails connecting small holes means voles.
Multiple clues together give you the most reliable identification. A single 2-inch hole could be several animals, but a clean 2-inch hole with no dirt pile near a stone wall in a wooded yard is almost certainly a chipmunk.