The red carpenter ant and the black carpenter ant are two of the most common types found in Canada. The red carpenter ant has a dark brownish-black body, with a reddish-brown upper body. The black carpenter ant is dark brownish-black all over.
Carpenter ants are from 6 to 25 mm (.24 to 1 inch) long. A carpenter ant’s body is divided into three segments, with a very slim waist separating the upper body and lower body. Their antennae are bent and in sections. Male and female adults have wings at mating time.
Carpenter ants are well known for their ability to damage wooden structures. They are also a nuisance in homes as they search for food. Carpenter ants eat both plant and animal matter. Their natural food sources are insects, other small invertebrates, and sweet body fluids from aphids and other insects. Protein and sweet foods found in and around homes also provide food for foraging workers.
Carpenter ants build nests by burrowing into wood. They dig tunnels (called galleries) much longer than those created by termites. The wood is not eaten, but thrown from the nest as sawdust-like shavings.
Outdoors, carpenter ants are found in dead trunks of standing trees, stumps, or logs, or under fallen logs and stones. They can sometimes mine sound wood, but they usually choose a soft type, like pine.
Indoors, because they prefer moist, decaying wood, carpenter ants can signal a moisture problem, or wooden structures that are decaying. As well as tunnelling in the trim of buildings, wooden steps, and window sills, ant colonies can nest in houses without attacking structural timbers, using hollow spaces like wall voids, attic spaces, and hollow doors. They can even be found behind books in libraries, behind drawers in dressers and cabinets, and in styrofoam insulation.