Black Carpenter Ant

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Black Carpenter Ant

Camponotus pennsylvanicus

Status: Not Listed

Classification: Invertebrate


Black carpenter ants live in colonies with workers and a queen. The queen is slightly bigger than the worker ants, with a larger thorax and wings, while most workers are wingless. They are about a half-inch (1.2 centimeters) long and completely black with yellowish hairs on the abdomen.

Depending on where black carpenter ants nest during the year determines whether they are seen as an interesting insect or a costly pest. Carpenter ants naturally nest in dead logs and wood in forests. They chew (but don’t eat) wood to build nest cavities and tunnels. This action helps in decomposition and breaking apart decaying logs. However, when eastern carpenter ants build a similar nest in the side of buildings or the support beams of a home, they become a serious pest. Their nest could weaken the structure of a house.


Black carpenter ants live east of the Rocky Mountains in woodlands, forest edges, and suburban communities.


If a carpenter ant is seen indoors, it might just be searching for food. Carpenter ants do not eat wood, but they only chew it to make a nest. Instead, workers spend a lot of their time looking for plants and smaller insects to eat.

In addition, black carpenter ants are actually farmers. One of their favorite foods is a dew-like juice produced by aphids. The black carpenter ants will feed and protect aphids in order to eat the sugary dew.

Life History

After a few years, when a colony is large enough, the queen will produce winged males and females that will leave the nest to breed and start new colonies.

Fun Fact

The best way to protect a home from a black carpenter ant infestation is to keep outdoor wood structures dry. Black carpenter ants can easily chew through wet wood.

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