As the weather starts to warm this spring, millions of legs are on the march for higher and drier ground. Millipedes have begun to invade homes, garages, patios, and front porches. As spring rains move in, these seasonal visitors move out to look for drier habitat and become a nuisance.

If you are being run over by millions of tiny legs, here is what you need to know about dealing with thousand-legged worms.

Millipedes are wormlike arthropod relatives of insects. Their brownish-black bodies are cylindrical and slightly flattened with many body segments. They can be distinguished from centipedes by the number of legs. Millipedes have four legs per segment, while centipedes have only two. The legs ripple as they move and may not be seen unless you view the insect from the side. As a defense mechanism, they will often curl up into a watch-spring shape if touched.

Millipedes are part of Mother Nature’s recycling program. They can usually be found in damp locations outside the home. However, early spring rains can chase overwintering adults out of their hiding spots and into homes. They feed primarily on decaying organic material and leaf litter and do not bite people nor damage household furnishings directly. They will leave a mess and give off an odor if crushed.

Control begins by drying out moist areas and cleaning debris and decaying organic material from around the structure. Removing their habitat can reduce their populations. To prevent them from coming inside, caulk around all openings in the foundation and around windows and doors.

Spraying insecticides that have the active ingredient cyfluthrin, proxopur or resmethrin in a 3-foot band around the outside of the house will take care of millipedes before they move in. However, do not be surprised if more adult millipedes appear in a few days as these chemicals do not have a long residual. Read and follow label directions.

– Bruce Chladny is horticulture agent at K-State Research and Extension-Douglas County. For more information, call him at 843-7058 from 8 a.m. to 5 p.m. weekdays.