Earwigs: The creepy, crawler is making its presence known around Central Iowa

Marlys BarkerNevada
Journal Editor
Earwigs: The creepy, crawler is making its presence known around Central Iowa

Summer hit in the past two weeks, and the onslaught of the earwig population hit right along with it. What is it about these creepy little black bugs, with the pincers on the front, that brings them on so heavily at this time of year? Why do they invade our homes and porches? Are they dangerous? This article will help you better understand this one sign of warm weather that most of us could do without.

“Every day I pick at least a dozen (earwigs) out of our pool. I’ve never seen so many in my life! What is up with them?,” asked Laura Melton of Nevada.

“I picked up a washcloth off of the bathroom counter and three fell out…so naturally I drowned them in the sink,” said Tiffany Cornelius of Iowa Falls, a former Nevada Journal/Tri-County Times reporter. “Everything I’ve read says they like cold, damp places. So bathrooms and kitchens and basements make sense, but we’ve been finding them in every room. Ugh!”

The earwig, according to Donald R. Lewis, professor in the Department of Entomology at Iowa State University, has a much higher population in Iowa the past few years than it did previously thanks to the region’s wetter than normal springs.

“This is weather-driven,” Lewis points out. “In drought years, and especially after a series of drought years, the (earwig) population is very low.”

The most common earwig, Lewis said, is the European earwig, an exotic species that is now found nationwide here. Earwigs are an insect, but are in a separate group and not closely related to other kinds of insects, Lewis explained. They have their own insect order and are recognized by those large pincers on the end of their abdomens. “Though earwigs have wings in the adult stage, they rarely fly,” he said. “They are active at night and better runners than they are fliers.”

Earwigs are most commonly found in damp outdoor locations, because they feed off decaying organic matter and small insects. But unfortunately, many people are seeing them in homes, and Lewis said there is bad news and good news about finding them in your dwelling.

Among the bad news is the fact that they’re difficult to control. “Earwigs don’t travel in a certain, treatable space, and they don’t go back to hide in the same spot,” Lewis said. “So spraying indoors (such as a light spray to every edge and corner of the room) is not recommended.” He said while people can spray door thresholds, the cracks between foundation and siding and other cracks and gaps are where they come in, a spray in one place may not always work.

Dave Knudson, president of Preferred Pest Management, Inc., of Ames, said when they get calls about earwigs, which he refers to as “accidental invaders,” they have a two-fold approach for treatment.

“We power-spray around the outside of the house along and close to the foundation to create a barrier from further invasion. Indoors we apply a very low-odor product ‘crack and crevice’ along baseboards and openings to outdoors to take care of the pests that have come inside.”

He said the products used to control earwigs and several other common insects are found by many people to be almost odorless. “The application (of the chemical) is limited to where it is most useful, which makes it most effective with the least environmental impact.”

The most important good news about earwigs, Lewis points out, is that they are generally harmless. “Earwigs do not feed on the house structure, furniture, fabrics, people or pets. They are harmless except for the annoyance of being inside where we don’t want them. Earwigs may cause minor damage to flowers and plants,” he said, but “they cannot bite or sting, and they do not carry diseases.”

Lewis agreed with Knudson about the earwig as an “accidental invader.” Lewis said they are an outdoor insect that wanders inside by mistake through cracks and gaps, and the only reason they stay is that they can’t find their way back out. “They wander around the house til they desiccate and die… they’re not after anything.” Furthermore, Lewis said, a person could never raise earwigs indoors, because it is too dry. And this, he said, “explains why they congregate in tubs and sinks and around drains — moisture.”

Lewis said because the wandering earwigs that have come into one’s home are hard to manage; his best suggestion is to sweep or vacuum them up and discard.

Knudson said homeowners would be wise to eliminate moist conditions around their house. “Rake and remove dead materials away from the house,” he said, like mulch, dead leaves, firewood or other rotting organic materials that they feed on.

If people want to call for help, Knudson said he’s always happy to help. “We are happy to take calls or emails for more information or to request a quote/appointment for service,” he said, noting that the treatments for earwigs are usually done in the spring and fall.

Spring and fall are the critical times, Lewis agrees, because these are the times the ground is moister. “In general we see more earwigs in the spring and fall when the ground is moister, though up against the house, where there are mulch and watered plants, they are active and abundant all summer as well.”