Carpenter ants are found throughout the United States. There are about 43 species. Most of them are large, but there are several smaller species. They have a convex thorax which makes it easy to tell them apart from field ants, which have an indented thorax. Otherwise the two ants are very similar in appearance. Carpenter ants are polymorphic, meaning the workers are several different sizes. Common species found in homes are Camponotus herculeanus, Camponotus vicinus, Camponotus modoc, Camponotus nearcticus.andCamponotus pennsylvanicus.
Most species are active in the late afternoons and at night. They will nest under the slabs of homes and enter through expansion joints or around plumbing. They are also found in crawl spaces under homes that have them. They will be most common in areas where there is moisture. If there is damp wood available, they will make galleries to make their nests. The galleries will follow the grain of the wood. If left alone, they can hollow out and destroy structural wood. They don't eat the wood, they just carve out areas and create wood segments (frass). If they are in the house, they will forage for any foods available, including pet foods, candies, syrups, sugar and other sweet products. They will also feed on any fruits they encounter and will root through the garbage looking for grease, fat or meat scraps.
If you have carpenter ants in your home, they can do some damage, so you need to get them treated by a professional.