Leggy Pests: Centipedes and Millipedes

Common House Centipede
Millipede
We had a call from a concerned homeowner last week who had encountered a couple of leggy pests in her home. Were they millipedes or centipedes or something else? Without seeing a sample pest, it is difficult to say. Here are some facts to help homeowners not only identify the many-legged insects that sometimes invade, but also keep houses more secure against these infrequent invaders.

First, for purposes of identification, let's look at some of the differences between centipedes and millipedes. Adult centipedes are yellowish to dark brown, often with dark markings, and 1/8 to 6-inches long. They have one pair of legs per body part - usually a total of closer to 30-40 legs rather than the 100 their name implies. Common house centipedes are greyish-yellow with three stripes down the back and very long legs banded with white. Their last legs extend backwards, they move very quickly and they do bite. Unlike millipedes, centipedes do not curl up when disturbed.

Most millipedes are brown or black, and can range in size between 5/8 of an inch and 4-inches in length. They do not have millions or even thousands of legs, although they may appear to have that many. Usually their legs total less than 100. Unlike centipedes, millipedes have multiple legs per body segment, usually 2-4. Their back legs do not extend backward, they move more slowly than centipedes, and the do not bite. Only three species of millipede live in California, the common millipede, the bulb millipede and the greenhouse millipede. Both millipedes and centipedes will not live long indoors - they prefer to be in the yard where there is moisture and vegetation. For this reason, control begins outdoors.

Neither centipedes nor millipedes are dangerous, nor do they carry diseases. Although a centipede may bite humans, the bite is rarely more serious than a bee sting. In fact, centipedes and millipedes are useful in the garden, feeding off other pests. But if you want to control them, the methods are similar. Remove any moist harborage in the area, like wood debris, rock piles, grass clippings, compost and leaf litter. Indoors, dry out any moist areas such as basements or bathroom closets. Rarely is chemical intervention necessary. Remember, if you do see one of these temporary invaders - they will not be able to survive long in your house, and are actually good for the yard. If you want to read more about centipedes and millipedes, click here or call us at Centurion.