Q I've noticed several small round holes, about the size of a half-dollar, in the dirt near our foundation. Are these garter snake holes? How can we tell? If we fill them up, will the snakes go away?

A Snakes don't dig their own holes. Sometimes, however, they use holes dug by other animals. Identifying the culprit can be difficult. Here are some tips:

If you see burrows (usually shallow) with no soil piled near the entrance, here's the likely culprit and what you'll see:

An eastern chipmunk: 2-inch entrance near stone walls, rock gardens or foundations, in brush, open woods or gardens.

A 13-lined ground squirrel: 2-inch or less entrance in open areas with short grass.

A meadow vole: 1- to 1 1/2-inch entrance in open areas with heavy vegetation.

A shrew: 1-inch entrance in open areas or woodlands, with a tunnel just under the duff. (Some shrew species may appropriate vole burrows and runs, and several may occupy one burrow system.)

A Norway rat: 2- to 3-inch entrance near or under buildings, wood piles, shrubbery or rubbish and near a dependable water source (stream, sewer, toilet, etc.). Several rats may occupy one burrow system.

A muskrat: 4-inch entrance near a lake, stream or wetland.

If you see mounds of soil that cover burrows, leaving the entrance visible, the digger is an eastern mole if the mound is conical. But if it's round or heart-shaped, the culprit is a pocket gopher.

If you see multiple tunnels near the surface that raise sod or soil, but the tunnel entrance is usually not visible, blame the eastern mole in upland areas. Near streams or swampy areas, it's the star-nosed mole.

When you find deep burrows with excavated soil spread around the entrance, you've probably found a badger's burrow if the entrance is 12 inches wide and it's in a field, grassland or prairie. A burrow with an entrance of 10 to 12 inches found in fields, woodlands, under decks or building foundations is most likely caused by a woodchuck.

Keep snakes away

In any case, filling the hole is unlikely to convince a snake (or other habitant) to pack up and leave.

The best way to keep snakes away from your home is to make the environment inhospitable to them. Remove boards on the ground, wood and rock piles, weeds or growth near foundations and similar hiding places. Clean up any spilled birdseed or pet food outdoors to discourage rodents, on which snakes feed.

Information from University of Minnesota Extension Service

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