seal  Purdue News

June 3, 2004

Sometimes molehills seem like mountains

WEST LAFAYETTE, Ind. - Moles can make landscaping look more like moonscape, and the only way to halt the destruction is trapping because "voodoo" control methods don't work, according to a Purdue University expert.

Eastern mole
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"Moles eat small invertebrate animals - insects and worms," said Tim Gibb of the Purdue Plant and Pest Diagnostic Laboratory. "So, using poison peanuts or other bait won't work since moles don't feed on seeds, alfalfa pellets or any of the other baits that are sold to kill moles."

He said consumers should be wary of claims about schemes to drive moles away.

"Any book having to do with gardening and landscaping usually has advertising about what I call voodoo controls for moles," Gibb said. "This includes putting mothballs, human hair or chewing gum in their tunnels, or using pinwheels or ultrasonic devices to scare moles away. The reality is that these just don't work."

Moles won't eat bulbs or plant roots, although they can damage them. Moles also don't harm people or pets, but they can make a beautiful lawn look like a minefield.

This means a decision must be made on whether trapping is less of a nuisance than the critter itself, said Gibb, who also is a Purdue Turfgrass Integrated Pest Management team member. Those utilizing traps need to determine the proper type of trap, how to use it and where to place it.

Spring and fall are the best times to trap the small, subterranean mammals because they are nearer the soil surface, he said. That's also when people often become aggravated by the presence of the small, burrowing mammals as their tunnels and mounds create miniature mountain ranges in yards, gardens and golf courses.

Gibb said the visible tunnels, or runs, occur because moles are following their favorite meal - earthworms. Worms - and mole runs - tend to be nearer the surface during spring and fall when soil is wet and soft. Summer's dry ground and winter's frozen ground drive worms and moles deeper so the ridges or tunnels indicating their presence disappear, fooling people into believing the moles have moved on.

Two effective mole traps can be used depending on where the moles are active, Gibb said. A scissor trap is better for use in subsurface, or deep, mole runs. A harpoon trap is best for visible runs that are near the surface during wet seasons.

The best trap placement is in a run the mole uses regularly, Gibb said. Usually this is a run that is in a straight line as opposed to squiggly tunnels that are generally food foraging routes.

"If you find a long, straight run, especially one that follows a structural guideline such as a curb or a gutter, it's one that they use regularly to go from their nest to the foraging area," Gibb said. "You can determine if a run still is being used by stomping it down flat, then checking the next day to see if it is pushed back up."

"The harpoon trap is usually easier for most people to use," Gibb said. "It just takes some practice to know which run the mole is using and how to set the trap."

Another option is hiring a professional trapper, who will charge about $50 per mole caught, Gibb said. Mole traps are available at most hardware, home repair and farm supply stores.

Writer: Susan A. Steeves, (765) 496-7481,

Source: Tim Gibb, (765) 494-4570,

Ag Communications: (765) 494-2722; Beth Forbes,
Agriculture News Page

Related Web sites:
Purdue University Plant & Pest Diagnostic Laboratory

Purdue University Department of Entomology

Indiana Department of Natural Resources

Purdue Extension Service

Related release:
Moles and myths: Are they friends or foes?

This Eastern mole is very common. They use their powerful front legs to dig tunnels in search of earthworms and insects that comprise their diets.

A publication-quality photograph is available at

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