Millipedes and Millipede Control

House Centipede | Centipede Control


General Millipede information

millipede Millipedes are oval, 1-1/2 inches long, segmented with many legs, coiling up when resting or dead. Every millipede has two pairs of legs attached to each apparent body segment. Most millipedes are brown or black, but some species are orange or red. Their diet consists of damp and decaying wood and plant materials. They may invade the house during extremely wet seasons.

Photo by Jared Belson
  • Millipedes are found outdoors in situations where there is moisture and decaying organic matter, such as under trash, grass clippings, mulch, rotting firewood, leaf litter, etc.
  • Their diet consists of damp and decaying wood and plant materials. They scavenge feeding on decaying organic matter.
  • They invade the house during extremely wet seasons or extreme drought.
  • Millipedes usually die within a few days of entering a structure unless there is a source of high moisture and a food supply.
  • Millipedes are active at night.

Recommended Measures of Control of Millipedes

Non Chemical Measures

  • Millipede control begins outdoors by removing harbor aging places that hold moisture, such as wood debris, rocks, grass clippings, and leaf litter.
  • Firewood should be stored off the ground.
  • Lawns should be watered in the morning to promote drying by the afternoon.
  • Flower beds should not be over mulched.
  • Entry into building should be prevented by sealing and caul king gaps around siding, windows, doors, pipes, wires, etc.
  • Large numbers of these structure-invading pests are easily controlled by vacuuming and discarding the collected material.
Any of the pyrethroids work but getting the insecticide to the millipedes is the challenge. Centipedes are a bit easier as they don't go as deep in the soil. Even with centipedes you may have to pull the mulch back from the foundation to expose the dirt.

Chemical Measures

  1. A good residual such as LambdaStar Ultra Cap 9.7 sprayed along entry points, cracks and crevices, baseboards is important. Even more important would be a good residual sprayed on the outside, in particular on the exterior walls that they are entering the home. During periods of heavy migration of millipedes, you will most likey have to repeat treatment.
  2. Granular products like Bifen LP Granules can be applied to mulched flower beds and heavily thatched turf areas where millipedes may be living. Be sure to treat these areas during periods when millipedes are found inside the home in large numbers. Repeated applications may be necessary to maintain control during periods of heavy millipede migration. The Bifen LP granules would be an additional treatment around the house to serve as a barrier. The advantage of granule treatments in addition to liquid residual barriers is that they hold up under rainfall. Repeat treatments of granules every 3 months

  3. Recommended residual insecticides:
    • LambdaStar UltraCap 9.7 or Cyper WSP work well, sprayed 3 feet out, along the foundation and 3 ft. up the exterior wall as well as sprayed around the entry points, like doors and windows. LambdaStar Ultra Cap 9.7 does not leave a visible residue, Cyper WSP, as a wettable powder does leave a visible residue, which is noticible against darker surfaces.
    • Repeat treatments of these suggested liquid residual insecticides every 3 months or as needed.
  4. For spot treatments: Use CB Invader HPX, sprayed around doors and windows and other places where these pests may enter premises is another choice to spray in the smallest of cracks and crevices because it has a crack and crevice tip. Repeat treatment of this aerosol once a month.