The queens are easy to see as they settle, shed their wings and search for crevices in decaying wood to begin their nest. Carpenter ants make two types of nests. If the queen finds moist, decaying wood, she tunnels into it to begin the main nest. This site must be permanently moist or the eggs and younger larvae cannot survive. Old nests can contain thousands of ants, but it takes several years for a new nest to build up to a few hundred individuals.
Main nests are usually outdoors in rotting stumps, trees or in decaying landscape timbers.
They can become established in houses where wood in the structure has begun to decay. Although Carpenter ants do not eat wood, they do tunnel into it to make their galleries. Once they establish a nest in damp wood they will eventually damage the structure by tunnel ling from the decaying wood into the sound wood. Carpenter ants also make satellite nests where they care for the older larvae and pupae that tolerate drier conditions. These nests are often in wall voids and eaves, ceilings or under insulation in attics or crawl spaces.