Millipedes are long, wormlike animals that are also referred to as worms, wireworms, and armyworms. While often mistaken for centipedes, millipedes are smaller (1 to 1-1/4 inches in length) with dark brown coloring and shiny, hard shells. They have long cylindrical bodies and have a habit of curling into a ball when they are disturbed. While the name millipede might imply they have thousands of legs, in reality they typically have 4 legs per body segment and at least 60 legs total, although some species can have up to 160 legs. Millipedes are harmless to humans as they cannot sting or bite. They also do not feed on plants or wooden structures. What they do feed on is decaying plant material and prefer damp, moist environments where they thrive. They are often found under leaves, plant debris, mulch, pine needles and other similar habitats.
While there is no set millipede season, they do go on mass migrations twice per year – once in the spring and once in the fall. These usually occur on warm, humid nights where they will emerge by the hundreds. Millipedes are outdoor pests so finding them inside your home means they have wandered in by mistake. In fact, millipedes cannot reproduce indoors. When these pests do make their way indoors, they are often found in garages and basements. Millipedes are nocturnal when they wander out of their hiding places roaming aimlessly. They eventually crawl back into holes or cracks (oftentimes in our homes) to escape the dryness of the impending daytime. They can often be found hiding under the edge of the garage door, in cracks along the exterior of your home, in sidewalk or driveway cracks, and in the gaps of your foundation.
Although millipedes are harmless, they can become a nuisance when they make their way into your home en masse. While there is no definitive millipede control method, the best practice is to try and keep them outdoors as best as possible. Because they often wander in through cracks and gaps, make sure these and other entry points around doors, windows, and foundations are sealed. They feed on organic material so keeping mulch, pine needles, and dead leaves away from your home will also help. Ensure gutters are not clogged and downspouts are angled away from foundations as this dampness will attract them in droves. Using insecticides on millipedes indoors is usually considered unnecessary as they will die in a short period of time due to lack of moisture. The best option to get rid of them indoors is to sweep or vacuum them up and discard them. Once the cold weather hits, they will become dormant… at least until springtime rolls around again!