Photo by Laurel Hansen

Colony propagation

Carpenter ants nest in wood, hollowing it out as the colony expands. They prefer a moist or humid environment, but will build in dry wood as well. The main part of the colony is usually located outdoors in a dead or dying tree, fence post, or firewood, but satellite colonies, consisting only of worker ants, alates, and pupae may be found inside the home. Some colonies have up to 20 satellites. Queens and brood are always in the main nest. Colonies can have multiple queens.

Once a colony is a few years old and has more than 2000 workers, it will begin to produce new reproductives to start new colonies. Winged males and females are produced in late summer or early spring. Reproductives may also be produced in the late summer and overwinter in the colony to emerge for mating flights in spring. They fly to new locations, where queens hollow out a nest and lay eggs. Infestations are often just recognized during the first warm days of spring when large winged ants emerge from walls or tree stumps.