For most homeowners, the back yard is a place for the adults to relax, the kids to play, the pets to romp and the flowers and lawn to thrive. For wildlife, however, a back yard is both hunting ground and a place to stash food. The size and location of holes animals dig help the yard invaders. Likely culprits range from furry rodents weighing less than 1 pound to armor-plated armadillos.
Tiny teeth marks at the base of a tree or woody shrub accompanied by nearby grass- or vegetation-hidden runways with several 1 1/2- to 2-inch-diameter holes leading to shallow, underground burrows belong to grayish- to blackish-brown voles. Voles dig day and night.
Squirrels are daytime diggers. In late summer and fall, they riddle yards with holes just deep enough to cache nuts or a few seeds. They also invade garden beds, digging deep enough to pull up and eat newly planted flower bulbs.
Raccoons, Skunks and Armadillos
Skunks and raccoons:
- make clusters of shallow, conical holes, usually measuring 2 to 4 inches wide.
- often leave claw marks around the holes.
- peel back newly laid sod as if it were an adhesive bandage to uncover worms and grubs.
Armadillo holes are usually 1 to 3 inches deep and up to 5 inches wide, but the surrounding area of disturbed soil or mulch may spread 3 feet.
- are cone-shaped and measure 8 to 24 inches wide and 2 to 8 inches high.
- lead to shallow, underground tunnels that cause ridges in lawns or mulch.
- often appear along walkways or garden edgings where the soil is loose and simple to dig.
- are plugged at their centers with clods of soil, but the plugs may be hard to see.
Pocket gopher mounds:
- usually appear in the loose, moist soil of irrigated lawns and flower and vegetable gardens.
- have visible plugs, usually in the center of their inward-curving sides.
- Hide the entrances to burrows lying 6 to 12 inches underground.
- lie just outside the 10- to 12-inch-diameter main entrances of the animals' underground burrows.
- occur most often on slightly sloping terrain.
Burrows Without Mounds
Chipmunks, ground squirrels, shrews and rats dig burrows without leaving mounds that give away their small entrances.
- Eastern chipmunks dig 2- inch-wide burrow entrances in the protection of decaying logs, stone walls, structural foundations or dense ground cover.
- Thirteen-lined ground squirrels dig openings of 2 inches or fewer in the open, with only short grass as protection.
- Shrews -- some weighing less than 1 ounce -- dig 1-inch-wide, open-ground entrances to shallow burrows located in open areas or woodlands. These entrances are typically discreet, with no soil piles visible nearby.
- Norway rats often share burrows that have about 1 1/2- to 2-inch-wide entrance holes. The holes are often near or under woodpiles, trash piles, structures, bushes and other locations with accessible water, food and shelter nearby.