Carpenter Ants are the largest of the common ants. The adults vary in length from about a quarter of an inch for workers and up to three quarters of an inch for a queen. They are either entirely black or black and red.
To establish their nest, carpenter ants seek soft, (and generally) moist wood, particularly wood that has weathered and begun to decay. These ants do not eat wood but excavate galleries to rear their young. Carpenter ants eject the wood in the form of a coarse sawdust or wood shavings. They are predators and typically feed on other insects.