Ant identification is not easy. Ants are social insects, living in colonies that may number thousands. Ant queens lay eggs. Ant colonies of some species have only one queen while other species may have many queens. Worker ants forage for food for the colony, care for the queen and the young, and defend the colony. Workers can be one size (monomorphic) or two or more sizes (polymorphic). Colonies may reproduce by swarming or budding. Ant nests commonly consist of underground tunnels and chambers. Some species make mounds of earth or ant hills. The queens stay in the nest and the workers bring them food. It is the workers you may see in and around the structure.

To control ants, pest control specialists must choose a treatment to target the infesting species. Ants must be treated differently, depending upon the species. Compare the ants you see with the ants pictured. A 30X hand lens will be required to correctly ID the smaller ants.

Acrobat ants are light brown to dark brownish black and have two nodes. They nest outdoors in soil, leaves, or wood; indoors in building voids and insulation. Acrobats are found throughout the U.S. Workers all one size with heart-shaped abdomen. May be found in wood previously tunneled by termites or carpenter ants, also in rigid foam insulation.

Big-headed ants are light brown to dark reddish brown, and have two sizes of workers (one size has enormous heads...seed crackers). Found throughout the U.S. it is rare that big-headed ants live indoors, preferring protected outdoor areas under logs, mulch, firewood, or patio blocks. Active forager, ant trails are common along sidewalks, foundations, and inside along baseboards and under carpets. Feeds on insects, protein, grease, sweets, seeds. There are several dozen species of this two node Big-Headed Ant.

Carpenter Ant

Carpenter Ants have one node and come in many varieties with different sizes and colors - tan, red, black. Carpenters hollow out dead, moist wood in trees, firewood, and fence posts to build nests but they don't eat wood. Inside, they build colonies in wall voids, foam insulation, eaves, crawl spaces. Found throughout U.S., they feed on insects and insect secretions during the summer but often invade structures in spring and fall looking for other food sources. Forage at night during summer months. Likes sweets. May switch off a bait.

The workers are brown to black in color. The cornfield ant is found throughout the United States. It is an occasional house pest in the northern states. It nests in lawns, between cracks in sidewalks, and under rocks. It enters homes in search of food, typically an uninvited guest at picnics. Likes sweets.

Ghost Ants are hard to see because they are tiny and pale with one node. The front half is dark, the back half and legs are light. Significant pest in Florida and Hawaii. In northern states, it is sometimes found in greenhouse infested plants shipped from Florida. Ghost ants usually nest outdoors, but they build colonies behind baseboards, in wall voids, in cabinets of buildings where they find food, feeding on dead insects, sweets, and other food.

Ghost Ant Identification Information Tapinoma melanocephalum

1/16 inch

The large yellow ant has one node, also known as citronella ants because of their smell when crushed, is recognized by its yellow/orange color. Common across the country, but not prevalent in the northeast and Midwest. As a soil nesting ant, it is usually found under logs, rocks, porches, patios, under concrete slabs and along building foundations. Occasionally swarm in crawl spaces, not known to go to any baits. Workers forage underground and colonies are difficult to locate.

Little Black ants are very small and black, two nodes, with workers all one size, similar to the Pharaoh Ant. Found throughout the U.S., but most often in the east. One of the more common house-infesting ants, Little Black Ants nest in wall voids and under carpets. May build outdoor colonies under rocks, logs, debris and forage to indoor food sources along baseboards and carpet edges. Likes sweets, fats, oils.

Pavement ants are all one small size, with two nodes, dark brown, with small stingers. Found in eastern U.S. (Florida to Canada) particularly in New England. Nesting along sidewalks and foundations of buildings, near firewood, stones, brick, mulch, etc., they forage in trails from outside colonies to indoor food sources, far from nests eating dead insects, greasy food, sweets, and pet food. Can access structures many times via plumbing pipes and move to upper building floors. May throw soil out on top of concrete slabs when inside buildings and swarm in buildings.

Pavement Ant Identification Information Tetramorium caespitum

1/8 inch

The Pharaoh ant is yellow with a reddish abdomen, two nodes and typically build nests in wood, wall voids, baseboards, etc. Colonies quite large, many queens. Found throughout the U.S., most commonly in southern states. In northern states species will nest in heated buildings. Common hospital pests. Likes fats/oils. May switch away from bait.

The small honey ant has one node, color varies from light to dark brown and can be found in eastern states, Canada, and in the plains states. This ant is typically found in shaded areas -- landscaping beds, under shrubs and will rest under slabs along expansion joints. This ant is very cold tolerant and is often the first and last species actively foraging. Likes sweets.

Thief ants are very small, two nodes, one size, light brown or yellow. They are found throughout the U.S. Thief ants nest near other ant colonies and steal food and larvae to feed their own colony. Outside they nest under rocks or logs, inside wall voids and behind baseboards. Move in trails along baseboards, seeking greasy foods, rarely sweet.