Carpenter ants are large black ants that live in many wooded areas around the world. They were given their name because they dig in wood such as trees or man-made structures as opposed to ants that live in tunnels in the ground.

Camponotus compressus - a species of carpenter ant

Unlike termites they do not eat the wood. They merely dig it out to build their colonies. In America they are most often located in the North East states.

Carpenter ants are a genus that includes over 1,000 different species.


Carpenter ants prefer to build their homes in decaying, moist wood. In a human home the ants are usually found under windows, eaves of roofs or under decks. This is because these areas are most prone to moisture.

Their primary nests require moisture and high humidity. This is where the queen, workers, eggs and newly hatched larva live. The eggs are especially sensitive and need high humidity in order to survive.

Older ants live in satellite nests which are connected by tunnels or located nearby, sometimes up to 100 yards away. These satellite nests can be drier.

Carpenter ants usually have ten or more nests per colony.

In each nest there will be large, medium and small ants. If the ants in the nest are all one size they probably aren’t carpenter ants. The more large ants there are, the older the nest is.

Each nest can have several queens which makes this genus of ants oligogyny. The queens tend to be intolerant of each other and separate to different parts of the nest. They become aggressive if they feel their territory has been invaded by another queen.


Worker carpenter ants are usually one fourth to a half inch long making them one of the larger types of ants. They are black or dark shiny brown in color.

The queen ants are larger, up to three fourths of an inch long, and have wings. These are the fertile ants.

Like other ants, carpenter ants have elbowed antennae that serve a multitude of functions, especially spreading and sensing pheromones.

The body of the ant is constricted between the thorax and the abdomen. Six legs attach to the thorax and internal organs are found in the abdomen.

They have an outer shell covering like many other insects instead of an internal skeleton like animals and people.

Breathing is done through holes in the shell. Oxygen is taken in and carbon dioxide leaves from the same holes.

They have strong claws or mandibles that they use to dig holes in wood.


Like many other ants, breeding occurs during a nuptial flight. The female queens and the male ants all take flight. The queen will mate with numerous male ants.

After mating the queen discards her wings and finds a place to build a nest and lay her eggs. The males die shortly after mating. As worker ants grow they assist in caring for and feeding the eggs as they turn to larva.


It takes sixty days for an egg to development into a worker ant. The queen lays the first batch of eggs in the nest and feeds them herself when they turn to larva.

They then develop into pupa and eventually into worker ants. The worker ants then help provide food for the next batch of eggs and larva. They forage for dead insects and eat honeydew secretions left by aphids. They eat the food and then regurgitate it in the nest for the queen and the larva.


Like many other ants, Carpenter ants forage for food. This means they eat other dead insects that they find. They also feed on some leaves.

When one ant finds a source of food they leave a trail by marking it with pheromones so the other ants can find their way to the food. When the food source is depleted they stop leaving the trail and it eventually fades away.

Carpenter ants cannot digest cellulose so they do not eat wood. They merely dig through the soft or decaying wood to make their nests.


Along with using pheromones for food trails, the queen also spreads pheromones to calm or excite the colony.

Using their antennae to smell pheromones ants are able to recognize which other ants are nestmates and which are not.

Disease Resistance:

Studies have shown that ants actually help each other fight disease by a type of immunization. Ants regurgitate food that carries proteases and antimicrobial material. This helps fight specific diseases that might otherwise harm the colony.

Impact on Environment:

Because carpenter ants cause damage to the wooden structures they nest in; they are considered a nuisance to humans. They leave a sawdust residue that is often a sign of their invasion.

If a few carpenter ants are seen it usually means there are many others that are residing in nests and are not seen.

To help eliminate the evasion of carpenter ants, wood should be kept dry. Rotting or damaged wood should be replaced. Exterior wood should be painted and sealed. Carpenter ants rarely make nests in healthy wood.

Dead logs and branches should be removed from around the home and bushes should not touch the house. Firewood should be stored away from the house, never against the house, and only small amounts should be brought inside at one time.

Unlike other ants, carpenter ants will usually not eat bait or take it to their nest. They will simply go around it and move on to their regular food sources.

In a forest, carpenter ants often work to eliminate dead or decaying wood and keep the woods healthier.

Exploding Ants

In Southeast Asia there are a species of carpenter ants that have extremely large mandibles. They can release toxins by rupturing their bodies this killing themselves and spraying a glue like substance to nearby invaders.

As a Food Source:

In Australia, Aboriginals regularly eat the Honeypot ant and its larva. In North America, lumbermen used to eat carpenter ants to prevent scurvy.


Carpenter ants are a fascinating member of the ant family and are fascinating to study due to their ability to work together in colonies and communicate with nestmates.