University of Illinois Extension

Main Navigation

Bugs - Bug Review - University of Illinois Extension

Millipedes, Centipedes & Sowbugs

Millipedes are hard-shelled, worm-like animals with many segments. Their legs are uniformly spaced along their body. Most segments bear 2 pairs of legs. The adults are 1-2 inches long and are brown, tan or gray. When disturbed, millipedes curl up.


Centipedes are flattened, elongate animals with numerous segments. Each segment bears 1 pair of long legs.

Sowbugs and pillbugs are gray, hard-shelled, oval-shaped segmented animals with 7 pairs of legs. When disturbed, pillbugs roll up into a tight little ball.



Most millipedes, sowbugs and pillbugs are scavengers, feeding on decaying organic matter. Often they are found in groups under leaf litter, mulch, tree bark, flower pots, damp cracks and crevices and refuse piles. Sometimes they may feed on roots and plant parts. Centipedes are predators that feed on small insects and spiders.


Millipedes, sowbug and pillbugs are slow moving animals that may enter buildings and cause annoyance. Because they need high humidity, they often die quickly indoors. They do not bite humans or damage articles in the home.


Centipedes are fast moving animals and may be annoying indoors . If threatened, they may bite. Stored food and other items in the home are not damaged.


Non chemical: If found indoors, remove by vacuuming. Discourage these animals by changing their habitat and removing their food source. Keep planting beds free of mulch along building foundations. Prevent accumulations of leaves and other organic waste. Remove potential moist resting sites, such as loose boards, stones and pots. Caulking cracks and crevices can keep most of these animals from entering the house.

Chemical: Contact your county Extension office for current pesticide controls.