Earwigs

The question almost everybody arrives with is whether the thing can hurt them. It is answered in the next section, from sources, before anything else on this page. The short version is no, and the reason the answer needs a section at all is that the folklore is older and better known than the entomology.

What This Page Carries

Can They Hurt You? No

Ohio State University Extension answers it in its opening sentence: “Despite their intimidating appearance, earwigs are harmless to people and, contrary to their eye-catching name, they do not seek to hide inside your ears.”

University of Nevada, Reno adds the detail that actually answers whether it can nip you, and the answer is that the part which can is not the part you are looking at: “They can pinch with their mandibles (jaws) if handled but are not known to be aggressive or harmful to humans.” The mandibles are the jaws at the front, not the forceps at the back.

And the building is not at risk either. University of Maine: “They are not known to cause any damage to homes or their contents, but they are definitely a nuisance, especially when they turn up in unusual places.”

On the ear itself, two sources are explicit. Penn State Extension explains the origin of the name and then closes it: “Actually, these insects do not crawl into the human ear.” Colorado State University Extension gives the same origin — “The name earwig originates from the superstition that these insects use their cerci to burrow into people’s ears.” A superstition, named as one, by the source.

What they can damage is plants. Ohio State: “However, these insects can cause serious damage to seedlings and chew large holes into specialty crops, flowers, and grain.” If you have a problem worth acting on, it is almost certainly in the garden rather than in the house.

What the Pincers Are For: Two Answers

Three extension services describe the function of the forceps and they do not agree. This page reports both positions rather than choosing.

• Defense and prey capture. Penn State Extension: “Earwigs use their forceps mainly as protective weapons, but they also use them to capture prey.” University of Maine says the same thing independently: “The pincers are used for defense and also to catch other insects on which earwigs sometimes feed.”
• Mating. University of Nevada, Reno: “Their pincers are used primarily for mating.”

Two of three give one function and the third gives another, and no source read for this page reconciles them. It is recorded here because a reader comparing pages will find both and is entitled to know the difference is in the sources rather than in the reading. What all three agree on is the part that matters to a person: the forceps are not a hazard to you.

What You Are Looking At

NC State Extension gives the description at order level: “Earwigs (order Dermaptera) are red-brown to black, elongate, flattened insects recognized by their forcep-like appendages (cerci) on the end of the abdomen.”

Most earwigs are not a household matter at all. Penn State Extension: “Only four or five species are common pests which invade homes.” Its fact sheet, like Colorado’s and Nevada’s, is about the European earwig, Forficula auricularia, which is the one that turns up indoors.

One more identifying trait, and it is the one people remember. Penn State: “If disturbed, these insects have a foul odor.”

Why They Are Inside

An earwig indoors is usually looking for somewhere dark to spend the day, not for your food or your building materials. Penn State Extension: “Earwigs are active at night and hide during the day in cracks and crevices.” and “This insect hides in any dark, moist crevice, such as balled plants and boards.”

University of Maine describes the route in, and it is the whole mechanism: “Generally, they do not actively infest homes, but as they go up the foundations, any open area around the sill, door or window that will allow them to enter becomes an invitation to move in.” They climb the foundation from the shelter beside it and come in at the first gap. That is why the work below is aimed at the strip of ground next to the wall rather than at the room.

If the insect you are finding is not this one, our silverfish and firebrats page covers the flat, fast, tapered insect of damp bathrooms and basements, and our camel crickets page covers the humpbacked jumping one of crawl spaces. All three share a root cause and none of the three repeats the others.

Moisture and Harborage: the Root Cause

Every source that gives control advice puts the daytime hiding place first, and the hiding place is usually mulch. University of Maine explains why mulch in particular: “Because earwigs also feed on decomposing organic matter, compost and mulch may provide food and shelter.” It is shelter and a meal in the same place.

Colorado State University Extension makes the instruction spatial, which is what makes it useful: “Clear the area next to the home of sheltering debris (including mulches) used by earwigs, particularly near likely points of entry (doorways, window wells).” Not the whole garden — the band of ground beside the wall, and hardest of all beside the doors.

Reducing the Outdoor Population

Three sources, three habitat instructions, and they stack rather than compete.

• Ohio State University Extension: “Reducing mulch layers and landscape structures can aid in eliminating earwig shelters and reduce earwig breeding in soil chambers and spaces beneath landscape stones and timbers.” Note that this one names breeding, not only shelter.
• University of Nevada, Reno: “Remove refuge sites such as creeping groundcovers or thick mulches near vegetable gardens.”
• Ohio State again, and this is the indirect one: “Use plants that are less vulnerable to aphid and scale infestations, or treat these insects when they are discovered, since European earwigs thrive by consuming soft-bodied insects.” Remove the food supply rather than the insect.

Trapping, and Why Nothing Here Is for Sale

Four sources describe trapping earwigs. Every device they describe is one you make yourself, out of something you already have. That is not an editorial preference; it is what the publications say.

• Colorado State University Extension: “Earwigs can be trapped in rolled-up, moistened newspapers.”
• University of Nevada, Reno: “Monitoring traps can be created, which consist of shallow cans or containers placed at ground level and filled with a half inch of oil.”
• University of Maine: “Traps can be made from two pieces of grooved wood placed together; these can be leaned against a tree or the foundation.”

And the timing is published, which matters more than the trap. University of Maine: “Place traps in earwig areas at dusk and empty traps the following morning.” The insect is nocturnal, so a trap set in the morning and checked at night is set against the animal’s schedule rather than with it.

The Case for Leaving Some Alone

Two sources describe the earwig as a predator of garden pests, and one puts both sides of its character in a single sentence.

Colorado State University Extension: “However, the main food of earwigs is insects, including plant pests such as aphids.” NC State Extension: “Some earwigs are predators, feeding on aphids, whereas others feed on living plants and may become pests in greenhouses and on vegetable, fruit, ornamental, forage and field crops.”

They also have natural enemies already at work. University of Nevada, Reno: “Spiders, centipedes, poultry and fowl often feed on earwigs.” A garden population is not usually a problem to be eliminated, and none of these sources asks a reader to eliminate it.

What Is Not Named Here, and Why

The traps are all homemade, so there is no trap to card. Every device the six publications describe is made from newspaper, a can of oil, or two boards. Naming a purchasable trap would mean ranking it against a specification none of these sources publishes.

Diatomaceous earth appears in none of the six. That is worth stating precisely: it is not that the sources rate it poorly, it is that they do not mention it at all. A card for it would have to rest on something other than the publications this page was built from, and nothing else was read.

Nevada gives sticky traps a single sentence and no specification: “Sticky traps can also be used around sheltering areas.” That is a practice, not a criterion. There is nothing in it to measure a product against, so nothing is named.

The same applies to sealing. The sources name the openings that matter — the sill, the door, the window, in Maine’s sentence above — but none of them publishes a material, a gap width or a product standard for closing them. The advice is real and the ranking criterion is absent.

When to Call a Professional

The honest answer is that none of these six sources describes an earwig problem as one needing a professional, and this page will not invent a threshold they did not publish. What they describe is a habitat problem next to a building, addressed by clearing shelter and closing gaps, with trapping as monitoring.

Ohio State does note that insecticide may be needed to eliminate large populations, and both Ohio State and Colorado State describe insecticide use as something applied at points of entry and outdoors rather than broadcast indoors. No product, rate or application method is given on this page, because a reader who has reached that point is choosing between a labeled consumer product and a licensed applicator, and that choice depends on the label and the state rather than on us. Our choosing a pest control service page covers what to check before hiring.

Questions

Sources