One of the disturbing sites around the home is a house centipede darting across the bathroom counter. It's enough to make anyone flinch. But before you grab the slipper to mash the unfortunate critter, let's learn more about them. First, centipedes are beneficial. They are predators and they eat small insects, insect larvae, and spiders. That's a good thing, though most homeowners take a different point-of-view and consider them a nuisance.
Need more good news? Centipedes are harmless to people, pets and property. The common house centipede has an elongate, flattened, segmented body with one pair of legs per segment. There are 15 pairs of very long, almost thread-like, slender legs on the 1 1/2 inch long body. Each of the 30, fragile-looking legs is almost equal to the length of the body and is encircled by dark and white bands. The body is brown to grayish-yellow with three dark stripes on top.
Though house centipedes are found both indoors and outdoors it is the occasional one on the bathroom or bedroom wall, or the one accidentally trapped in the bathtub, sink, or lavatory that causes the most concern. However, these locations are not where they normally originate. Centipedes prefer to live in damp portions of basements, closets, bathrooms, unexcavated areas under the house and beneath the bark of firewood stored indoors. They do not come up through the drain pipes.
Centipede or Millipede? Both centipedes and millipedes are wormlike, multi-legged animals (and therefore, detested). Both are frequently noticed in the garden or house. Telling the two apart is fairly easy if you allow yourself to get close enough to count the number of legs present on any mid-body segment. Millipedes, the harmless “recyclers" of garden mulch, have two pairs of legs per body segment, twice the number of legs found on centipedes.
If you have more centipedes in your house than you can stand (remember they are beneficial) try to dry up and clean, as much as possible, the areas that serve as habitat and food source for centipedes. Residual insecticide sprays and dusts can be applied to potential hiding places such as dark corners in basements, baseboard cracks and crevices, openings in concrete slabs, under shelves, around stored boxes, and so forth, but their effect is very limited. Better to live and let live or capture and discard the occasional nuisance.
House centipede. Photo by Laura Jesse