Purchase photos

Miller migration bugs residents

4/24/2012

By RANDY GONZALES

rgonzales@dailynews.net

One certainty of living in western Kansas is the annual migration of miller moths.

Millers, as the critters commonly are called, are army cutworm moths. In the spring, they migrate across Kansas to the mountains of Colorado.

Along the way, they can become a nuisance.

"A lot of millers in the garage," Connie Desbien, Palco, said of the farm where she works. "There's gobs of them out there."

A garage is not an unusual place to find millers in the daytime. They crawl into cracks and crevices seeking dark areas for shelter before resuming their travels at night. When opening a screen door or car door in the morning, dozens of the bugs might come flying out.

"We've noticed them around our house," said Stacy Campbell, Ellis County Extension agriculture agent. "They're a problem every year."

Miller moths have distinctive wing markings. The females tend to be grayish white, while the males are more of a brownish color. Other than just being a nuisance, the moths can be a problem for farmers, too.

"They like to feed on alfalfa and wheat," Campbell said. "Actually, with the mild spring, we were kind of wondering if it would be a problem with wheat. I really didn't hear of any reports.

"Once in a while it might be a problem in those crops, (you might) have to spray for them. But in the 12 years I've been here, I can remember one year for sure they were eating on young wheat in the spring."

Mostly, though, it's finding the millers in every nook and cranny that's the problem. If you try to swat a miller, the result is a dusty smudge left on the wall. That fine, powdery substance on the moths' wings is how they got their name. The fine scales that rub off reminded people of the dusty flour covering clothing of people who mill grain. Hence, the "miller" moth.

Other than swatting them or using a vacuum cleaner, a way to catch millers is to use soapy water in a pan or bucket and put a light near it to attract them. The other option is just to wait them out for the few weeks they're around.

The moths go to Colorado to feed through the summer at cooler, higher elevations, accumulating fat reserves. They make a return trip in the fall to deposit eggs but are less noticeable because their numbers dwindle due to predators, such as bats and also Grizzly bears once they reach the Rockies.

While humans see millers as a nuisance, a Grizzly bear sees them as snack food. A single moth possesses half a calorie of fat content. The Kansas Insect Newsletter estimated a bear obtains 20,000 calories of fat on a daily basis by consuming 40,000 moths per day.

"They go to Colorado, vacation there, become bear food, too," Campbell said.