What Made That Tunnel in My Yard?
By Chris Williams on July 7, 2016.
We have these strange tunnels in our lawn. There are raised bare areas in the grass that connect together like something moved underneath. We haven’t seen any critters. Is there a way to tell what’s tunneling? D. E., Saugus, MA
In our part of the country, the tunnels probably belong to either voles or moles. The lawn damage caused by these two animals is often confused. While voles have underground burrows, their runways are above ground, leaving tracks or worn areas through the grass. You should also see several holes in the ground that lead to their burrows. Moles, on the other hand, burrow and tunnel completely underground but you can often see humped-up soil above their tunnels. Moles also leave mounds of dirt (“mole hills”) above their underground runways.
Voles are rodents and are related to mice (see Mice or Voles in Your Yard?). They look like fatter, cuter, house mice with smaller ears and a short tail. Moles are not rodents and no one would call them cute. Moles are gray with a long pointed snout, barely visible eyes and ears, and large digging claws on their front feet.
Moles Remain Underground
From your description, it’s hard to tell which animal is causing the damage but it sounds more like moles. The fact that you haven’t seen an animal also suggests moles since they rarely appear above ground. Moles are often mistakenly blamed for damaging garden plants, but they feed underground on earthworms and grubs. Mole tunnels are actually hunting tunnels and are abandoned when the food source in that area is exhausted (see Mole Tunnels Everywhere!). Abandoned tunnels may partially collapse leaving irregular holes.
Voles Use Aboveground Runways
Voles feed on plants, including grass. In winter, they forage for seeds and will chew roots and bark at the base of trees. Voles clip the grass at the base creating 2-inch wide paths. Vole runways may be hidden by tall grass. Runways and grass damage can be very obvious when heavy snow cover melts in the spring because voles actively forage all winter under the snow (see Vole Winter Damage to Lawns and Trees).
To further confuse the issue, voles will sometimes take advantage of abandoned mole tunnels and use them as ready-made runways. So, while you may see mole tunnels, they could be currently occupied by voles. If voles are using mole tunnels, you should see obvious entry and exit holes into the burrow system made by the voles, not the moles.
A pest control professional can trap either of these yard pests. Call Colonial today. To read more, see The Difference Between Moles and Voles.