Purdue Extension Service

Vanderburgh County, Indiana

New Weapon Against Moles

By Larry Caplan, Extension Horticulture Educator, Vanderburgh Co., IN

For the Evansville Courier and Press, March 20, 2005

One of the major annoyances of suburban life is moles. Well, not so much the actual little critter, which is kind of cute and fluffy, with beautifully silky fur. It's the annoying tunnels and mounds of soil that moles leave behind to advertise their presence in our yards that most people object to.

For years, all of the research information I've ever read about stated that the only guaranteed way to get rid of moles is to use traps. Mole traps are not easy to use: you must place them over an active run, and they must be set properly so that the mole will pass under them and set them off. There is a small amount of danger to children and pets setting off the traps. And, there is the "yuck" factor to deal with, since you are trying to run metal harpoons through the mole.

However, traps are still preferable over the other methods people use, since at least the traps have a chance at working. Trying to starve the moles out by killing grubs doesn't work, since the moles also eat earthworms, which are not affected by the grub insecticides. Flooding and gassing them won't work, because their tunnels are too extensive. They ignore moth balls, castor beans, chewing gum, and other such objects. And, since moles are insect-eaters, the standard mole baits and poison peanuts have no effect on them.

However, there is a brand new mole bait on the market that, according to Purdue University specialists, actually has a chance of working. The product is called "Talpirid," and is manufactured by Bell Laboratories.

What makes Talpirid so special? Well, for starters, the bait mimics the mole's natural food: earthworms. It's about the same size and shape as an earthworm, and is made out of a material that has been tested and proven to attract moles. The bait's size, shape, texture, and (I assume) taste and odor are similar to a real earthworm, so moles will actually consume it if they find one.

The active ingredient of Talpirid is a chemical called bromethalin. According to the product's website ( http://www.talpirid.com ), each "worm" contains enough toxin to kill a mole within 24 hours. According to the Material Safety Data Sheet (MSDS), the chemical is considered of low human toxicity.

To use the bait, however, is almost as complex as using the traps. You must first find an active tunnel, one that is used repeatedly. The label explains how to do this (as does Purdue's free publication on mole control), but briefly: poke a few small holes in any exposed runways with your finger or a stick. Mark these sites, and check them a couple of days later. If the tunnel has been repaired, then this is one that a mole uses repeatedly. Usually, you have better luck if you seek out the deeper traveling tunnels that are found between two mounds of soil.

Once you have found an active tunnel, make a hole with a stick or wooden rod. Drop one worm down this hole, and carefully reseal the opening. Be sure to wear unlined rubber gloves when handling these worms (or any pesticide). Repeat the baiting every 5 to 10 feet of active tunnel. Be absolutely sure to put the entire worm underground; this product is toxic to birds, fish and other wildlife.

About a week after application, repeat the procedure for locating active runs. If the moles in your yard have been poisoned, the opened tunnels will remain open. If the openings are closed up, or new tunnels are discovered, repeat the baiting process.

As I said before, this product is very new. There is not a lot of feedback yet as to how effective Talpirid is. Be aware that if you live next to a field or wooded area, you will constantly get moles entering your property in search of food, so this is by no means a permanent fix. Also, according to Purdue animal damage control specialists, baits of this nature will be most effective when the natural food supply isn't readily available, such as right now. Once the summer rolls around and there's lots of insects and real worms to eat, the bait won't be quite as attractive to the moles.

Talpirid should be available in selected garden centers and farm supply stores. If you have problems locating the product, drop me a line. If you want a copy of Purdue's free publication on mole control (which won't mention Talpirid yet), contact the Purdue Extension Service at (812) 435-5287, or click here.