ThermaCell repelling appliance provides welcome skeeter relief

Clouds of mosquitoes flew up from the grass to greet us as we stepped out of the truck on a recent Sunday morning for a couple of days at the trailer, the family getaway in northwestern Minnesota.

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Clouds of mosquitoes flew up from the grass to greet us as we stepped out of the truck on a recent Sunday morning for a couple of days at the trailer, the family getaway in northwestern Minnesota.

Spending any time on the deck didn't seem like it was going to be an option.

As much as I hate mosquitoes, I was almost glad to see them -- especially in such biblical numbers -- because it meant I'd have an opportunity to put the ThermaCell I'd recently gotten to the test.

I did, and to put it bluntly, I'm sold.

Marketed by the Schawbel Corp. of Bedford, Mass., the ThermaCell is a mosquito-repelling appliance (for outdoor use only) about the size of a walkie-talkie that uses a butane cartridge to heat a small pad containing a chemical called Allethrin.


Described as an "area repellant," Allethrin is a synthetic version of a natural insecticide found in chrysanthemum flowers. Each ThermaCell provides a 15- by 15-foot zone of protection; one mat has enough repellant to last four hours, and the butane cartridge powers the unit for 12 hours. Replacement mats and cartridges are available when the originals run dry.

I'd first heard of the ThermaCell last September when Darin Heller, a cousin from Afton, Minn., recalled his experience with one of the units during a bear hunt in northwestern Minnesota.

He said the ThermaCell kept the mosquitoes from eating him alive.

"It was incredible," he said. "I went from full panic from the assault to the most pleasurable and relaxing time on the stand. It is like e-mail, voice mail, cell phones ... heck, the internal combustion engine. How did we function" without it?

That's a pretty strong testimonial from a hunter who received no endorsements or favors from the company.

Personal test

After hearing about Heller's ThermaCell experience, I made the rounds of local sporting goods stores last September hoping to buy one or two of the units, which retail for $25.95, but they were all sold out. So, when I spotted them at the Cabela's store in Rogers, Minn., this spring, I picked up a couple of the basic appliances.

A few weeks later, the company sent a couple of its basic units and new LED lanterns to test.


That recent Sunday at the trailer, the mosquitoes were beyond horrible when I fired up one of the ThermaCells at dusk on the deck, just to see if we'd be able to sit outside without being eaten alive.

We let the unit run about 15 minutes before venturing outside. I was skeptical, but we were able to hang out on the deck in comfort. Mosquitoes continued to swarm on the lawn but were reluctant to venture into the field of the ThermaCell. And the few mosquitoes that did acted like they were drunk.

Later that night, after we'd shut down the unit and gone back inside, clouds of mosquitoes swarmed to the light of the kitchen window next to the deck.

That did it for me: I was convinced.

On the river

Peter Howard Jr., who's working the Grand Forks stretch of the Red River as part of a creel survey for the North Dakota Game and Fish Department, also tested one of the ThermaCell units I received. His job requires him to spend extended amounts of time outdoors, occasionally in mosquito-infested areas of the Red River beyond Grand Forks city limits.

Now, he says, the ThermaCell is a piece of gear that's every bit as necessary as the measuring board he uses to measure anglers' fish.

"I use it at work all the time, because there are times when I have to sit there and wait for people to put a boat in the water and take a boat out," Howard said. "I just have it going, and I don't get bit at all."


He also tried the lantern last weekend during a fishing trip to the Manitoba side of the Red River -- an area where mosquitoes are about as bad as they can possibly get right now -- and said it kept the bugs at bay even in the boat.

The bugs were especially bad Monday afternoon when the wind died.

"We turned it on, and in five minutes, we weren't getting bit at all, and they were thick," Howard said. "It worked almost better than bug spray in a way. But prevention has been one of those things where if you don't have a screened-in tent or clothing, you're kind of out of luck, and that's not the case anymore. All you have to do is plug in the butane and turn it on. It's as easy as using a lighter."

If there's a drawback, it's that they don't work very well in rain unless they're kept away from the moisture.

Howard was fishing by daylight, but the lantern also would be ideal for night fishing. Retailing for $29.99, the lantern has eight LED lights and two illumination settings. Like the standard unit, it protects a 15- by 15-foot area.

In the park

Mosquitoes also go with the territory for Steve Crandall, manager of Turtle River State Park near Arvilla, N.D. Crandall said park staff now try to use ThermaCells if they're working in areas that don't require moving around too much.

"If I was going to recommend something to anybody camping, that's the tool I'd recommend," Crandall said. "They do seem to really work, and they're coming out with some bigger units now."


As another wet, stormy June comes to a close, it appears mosquitoes are going to be a way of life for the next several weeks, at least. It's not bad in city limits, where officials do a remarkable job of mosquito control that's worth every dime of the $2.50 it adds to my monthly water bill. But whenever I venture out of town, one thing's for sure:

I'll have a ThermaCell with me.

There are lots of gimmicks when it comes to repelling mosquitoes, but this definitely is not one of them.

On the web:

ThermaCell Corp: .

Dokken reports on outdoors. Reach him at (701) 780-1148; (800) 477-6572, ext. 148; or send e-mail to .

Brad Dokken joined the Herald company in November 1985 as a copy editor for Agweek magazine and has been the Grand Forks Herald's outdoors editor since 1998.

Besides his role as an outdoors writer, Dokken has an extensive background in northwest Minnesota and Canadian border issues and provides occasional coverage on those topics.

Reach him at, by phone at (701) 780-1148 or on Twitter at @gfhoutdoor.
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