Millipedes are slender, hard-bodied insects which look like short worms, they are slow moving despite the fact they have 2 pairs of legs on each segment, they are shiny brown and the adult is about 1 ½ inches long. Eggs are laid in clusters in the soil, the larval stage can be 4 to 5 years, with 7 or 8 instars; the life cycle may be several years.
Millipedes are most active at night, during the day they hide in cracks and crevices and under objects on damp soil. Patios, retaining walls, foundation plantings provide excellent breeding conditions.
Millipedes normally live outdoors, feeding on decaying matter and on tender roots and green leaves. Indoors they are objectionable but unlikely to cause any damage. They do not live long under the dry conditions normally found in a home.
At certain times Millipedes crawl about freely outdoors, along walls and climbing up them. They enter buildings through any small opening – cracks around doors, window, sashes, foundation cracks, poorly fitting doors. They accumulate in basements but may be numerous also on the ground floor. In the Fall, migrations may occur due to an urge to find suitable winter quarters. At other times heavy rains may force them out of hiding places to seek shelter on higher ground.
Millipede migrations can include considerable number and cover a wide area.
Millipedes thrive in damp organic matter, therefore:
1. Remove accumulations of leaves and other vegetation;
2. Clean up dead wood;
3. Dry out basements and damp areas;
4. Seal cracks in foundations and around door and window frames;
5. Install weather stripping at the bottom and around all ground level doors;
6. Ensure all screens fit snugly;
7. Keep basement clean.
Outdoors – Apply a suitable insecticide to likely hiding places such as cracks in walls, foundations and garage floors, spaces between stones in patios and retaining walls and along the edges of walks and curbs. With severe infestations, treat the foundations and a 10 to 20 foot band around the building.
Indoors – In basements, sweep up Millipedes and destroy them, or apply a suitable spray.