Carpenter Ants


Carpenter ants are large (¼ in–1 in) ants indigenous to many parts of the world. They prefer dead, damp wood in which to build nests. Sometimes carpenter ants will hollow out sections of trees. The most likely species to be infesting a house in the United States is the Black carpenter ant, Camponotus pennsylvanicus. However, there are over a thousand other species in the genus Camponotus.


Resides both outdoors and indoors in moist, decaying or hollow wood. They cut "galleries" into the wood grain to provide passageways for movement from section to section of the nest. They can leave "sawdust" behind that provides clues to nesting location. If this wooden complex happens to be a wall frame within your home, structural damage may result. Moisture is the key component to look for, when managing this species.

Carpenter ants prefer to attack wood that is moist, damp, or weakened by decay. Although dry sound wood is still vulnerable for infestation, it is less likely to be attacked. Indoors, nests are often found in wall voids, sill plates, and underneath siding. These nests are created because of moisture that may have softened the wood. Carpenter Ants are usually a problem from March to August, but appear during warm weather any time during the year.