In their natural surroundings, carpenter ants are beneficial insects. Excavation of galleries in wood has earned them their name. They are beneficial since they feed on many pests. They are the largest of our common ants, the brown or black workers measuring from 6 to 13 mm (1/4'' to 1/2") in length, while the queen may be more than 25 mm (1'') long. In late spring and early summer, mature carpenter ant colonies produce winged adults. These swarm in mating flights, and may be a nuisance around homes at these times. Outdoors, they nest in any wood that is in close contact to a moisture source, for example, stumps, landscape ties and wooden fence posts. In buildings, they often make their nests in hollow doors, in wood cabinets near dishwashers, in damp locations behind baseboards, fireplaces, window frames, and in basements and attics. Carpenter ants will rarely do extensive damage to wood. They usually limit the size of the colony to the area of the damp wood. Several so-called satellite colonies may, however, be constructed in the same structure. Carpenter ants may be seen in infested buildings at any time of the year searching for food at considerable distances from their nest. In some colonies, a dormancy period occurs for several weeks during the winter months. Although they chew their way through wood, leaving frass particles resembling sawdust, they do not eat wood. Instead, they feed on a wide range of insects, plant materials and, occasionally, on household foodstuffs.
Non-Wood Boring Ants
Ants are one of the most successful groups of insects. They are social insects that live in colonies which are usually located outside, but may enter buildings for shelter and/or food. Ants feed on practically every kind of food but those entering homes are often looking for sweets and/or protein-containing substances. Ants of concern in homes include Pavement Ants, Thatching Ants, Little Black ants, Harvester Ants, Moisture Ants and Carpenter Ants.