Pittsburgh, PA
August 7, 2020
    News           Sports           Lifestyle           Classifieds           About Us
Headlines by E-mail
Home >  Sports >  Outdoors Printer-friendly versionE-mail this story
Nature: Moles beneficial to back yards

Sunday, March 24, 2002

By Scott Shalaway

Certain phenomena, at certain times of year, generate a spate of mail and phone calls. The latest are the curious ridges that suddenly appear in people's back yards after late winter or early spring rains. They're created by moles which move from place to place by tunneling just below the turf's surface. This distinctive evidence of moles is easy to spot, but we rarely see these curious mammals above ground. They are fossorial -- they spend most of their lives in a complex system of underground tunnels.

Moles, though perhaps superficially rodent-like, are insectivores, kin to shrews. They have tiny beady eyes that probably detect only light and dark, no external ear flaps, and streamlined bodies well suited for life underground.


Send questions and comments to Dr. Scott Shalaway, R.D. 5, Cameron, WV 26033 or via e-mail to sshalaway@aol.com, and catch Scott on the radio Saturday afternoons from 2 to 4 p.m. on 1360 WPTT.


Their permanent tunnels are 12 to 18 inches below the surface and are virtually undetectable. These deeper burrows are usually near wooded areas, away from large expanses of open lawn. But their surface tunnels are quite evident, especially after spring and fall rains. Water loosens the soil and facilitates digging. And even though moles are one of nature's most efficient excavators, they prefer loose soil to hardpan. In fact, soil type is one of the factors that limits the distribution of moles. Soil must be loose enough to dig through, yet stiff enough to support the structure of the tunnel. Pure sand is too loose, and heavy clays are too dense.

Many home owners consider moles vermin. Their only interest is learning how to get rid of them. But in back yards, moles are beneficial. Their tunneling activity tills and aerates the soil. The tunnels direct moisture to deeper soil layers. They eat grubs in June as well as Japanese beetles, cutworms, slugs, snails, sowbugs, earthworms, other lawn pests and some plant material. All these benefits come at the cost of what many perceive as unsightly ridges in the turf. If you fall into this category, simply destroy the tunnels by stepping on them. Most moles lead solitary lives and inhabit an acre or more, so a single individual can be responsible for all the tunnels in an entire back yard.

Moles occasionally damage bulbs and other backyard plants, but not because they eat them. Rather, their burrows sometimes allow too much air into the soil, and roots can dry out.

Thanks to a variety of adaptations that make moles amazing digging machines, they can dig surface tunnels at a rate of one foot per minute. Deeper excavations proceed at a pace of 12 to 15 feet per hour. Given these phenomenal digging rates, it's no wonder many people fear their yards are infested with dozens of moles.

Among the anatomical adaptations that permit moles a fossorial lifestyle are greatly enlarged front feet. They are broader than long and tipped with strong, well developed claws. When digging, moles brace their hind legs against the tunnel's walls and dig with their powerful forelegs. They push the loose soil under their bodies and kick it backward. When too much loose dirt accumulates, they push it into old tunnels or up vertical shafts to the surface. These "molehills" look like miniature volcanos. If you find these mounds of dirt unsightly, consider them a renewable source of fresh topsoil and move them to a garden or flower bed.

Three species of moles occur commonly east of the Rockies. Hairy-tailed and eastern moles (they have naked tails) are the most likely species to be found in back yards. Star-nosed moles prefer wet, marshy soils and are easily recognized by the 22 fleshy appendages that surround the tip of the nose.

Moles breed in the spring. After a pregnancy of 30 to 45 days, the females bears a litter of four or five young. They leave the nest at about four weeks of age.

If you still consider moles a pest, visit a garden center. Grub-killing pesticides eliminate moles' favorite foods. If grubs disappear, moles will, too. Trapping moles is more easily said than done. But only golf courses and nurseries need be concerned about economic damage by moles.

A more tolerant attitude is a much less expensive way to deal with evidence of backyard moles that appears this time of year.

Back to top Back to top E-mail this story E-mail this story
Search | Contact Us |  Site Map | Terms of Use |  Privacy Policy |  Advertise | Help |  Corrections