Carpenter Ant Information

Carpenter ants have some distinguishing characteristics. One characteristic of a carpenter ant is its evenly rounded thorax.

Also, carpenter ants have one node between their thorax and abdomen.

Carpenter ants reside both outdoors and indoors in moist, decaying or hollow wood. They cut galleries into the wood grain to form their nests and provide passageways for movement from section to section of the nest. This activity produces wood shavings mixed with parts of dead ants which provides clues to nesting locations.

Carpenter ants do not eat wood, but they will feed on a variety of food people eat—particularly sweets and meats. They will also feed on other insects.

Reproduction

Queen lays 9 to 16 eggs the first year and may live up to 25 years. Eggs complete their life cycle in about 6 to 12 weeks.

Carpenter ant workers and swarmers (winged ants) are the most likely sign homeowners observe. The workers may be observed foraging for food. Swarmers usually are produced when a colony matures and is ready to form new colonies. These winged individuals often indicate a well-established colony. An additional sign of carpenter ant activity is the debris they produce from tunneling in the wood. Rough wood shavings mixed with parts of dead ants from the colony indicate carpenter ant nesting activity. A final sign may be the “rustling” sound sometimes heard as the ants go about their activity in the home’s wood.

More Information

Ants of the genus Camponotus are known as carpenter ants because they prefer to establish their colonies in galleries excavated from damp or damaged wood. Carpenter ants do not eat wood as termites do, but instead remove wood and deposit the debris outside of their nests in small piles.

Carpenter ants clean their nesting sites, and their galleries are not lined with mud or moist soil as termite galleries typically are. Carpenter ant workers keep their galleries as smooth as sandpapered wood.

Carpenter ants vary in size, ranging from 3.4 to 13 mm in length. One carpenter ant colony can contain different sizes of ants, depending on caste and responsibility. The color of carpenter ants also varies among species, ranging from jet-black to dark brown, red, black, yellow, orange, yellowish tan or light brown. They are most commonly black, but some carpenter ants exhibit both red and black coloration. They are common in many parts of the world.

Identification of carpenter ant species can be made only through careful observation of specific physical characteristics.

In natural environments, carpenter ants dwell in both dead and living trees, stumps and rotting logs. However, they may also establish their nests inside of homes and buildings where wood is found. Carpenter ants prefer to establish nests in areas where wood has been exposed to severe moisture.

Carpenter ants build two types of nests: parent colonies and satellite colonies. Parent colonies consist of a queen, her brood and workers. Satellite colonies consist of workers, older larvae and pupae. Workers create satellite colonies when the parent colony lacks sufficient space or when there is a suitable supply of food or water. There may be several satellite colonies associated with a parent colony.

All species of carpenter ants prefer decayed wood for their nesting sites, as these areas provide proper and consistent humidity and temperatures. Although carpenter ants do not eat wood, damage can be severe when nests remain active for several years. Over time, a colony can expand into several satellite colonies near the parent colony. Workers excavate wood for extra space, causing extensive damage to structures and woodwork.

There are 24 pest species of carpenter ants in the United States alone. For this reason, carpenter ant identification can be difficult. Size and color of carpenter ants can vary among species and even among individuals within one colony. Carpenter ants measure from 3.4 to 13 mm in length and can feature black, red, brown, yellow, orange, or red and black coloration. Although carpenter ants are among the largest ant species worldwide, size is not a reliable factor in carpenter ant identification because workers within a species vary in size.

Carpenter ants are often mistaken for termite swarmers, particularly during swarms when winged male and female ants fly out of their colony to mate. The most important characteristics to look for when identifying any winged ant are elbowed antennae, a pinched or constricted waist and a front pair of wings that is longer than the back pair. Termite swarmers will have straight antennae, a broad waist and both pair of wings similar in length.

Carpenter ants develop by complete metamorphosis: from eggs to larvae to pupae to adults. Adult carpenter ants have six legs, a constricted waist, three distinct body regions and a ring of hairs at the tip of the abdomen (best seen under magnification.)

Locating carpenter ant nests can be accomplished by following the trails of the worker ants themselves. Search for a clean and smooth cavity in the infested area, as well as slit-like windows in the surface of the damaged wood. Small piles of wood shavings can often be found below the openings. After identifying a colony, it is advisable to contact a pest control professional, as several satellite colonies may exist elsewhere within or around the home or building.