Ants can be a problem in and around the homes and other structures. Most will build their nests outdoors in the soil. Those that invade buildings usually will nest near foundation walls or under concrete slabs. Some species will nest in the walls of a building. Homes built on concrete slabs often have serious ant problems. Ants nest under the slabs and enter through cracks, heating ducts, and utility openings.
Carpenter ants are large (.25 to 1 in/0.64 to 2.5 cm) ants and reside in many parts around the world. They are attracted to dead, damp wood and build their nests. They do not eat it, like termites do. On occasion carpenter ants will hollow out sections of trees. The most common species in the United States is the black carpenter ant. They build their nests in hollow trees, stumps and sometimes in the walls of buildings. Carpenter ants leave small piles of sawdust where they enter buildings. Other species may nest in soil around the foundation or out in the yard. Carpenter ant species reside both outdoors and indoors in moist, decaying or hollow wood. They bore passageways into the wood to provide movement from sections of one nest to another. Particular parts houses, around and under windows, roof eaves, decks and porches, are more likely to be infested since these areas are vulnerable to moisture. Carpenter ants have the ability to damage wood used in the construction of buildings. Carpenter ants leave behind a sawdust-like material called frass that leads to their nesting location. Carpenter ant passageways are smooth and very different from termite passageways, which have mud packed into the hollowed-out areas.
Fire ants can be recognized from other ants by their copper brown head and body with a dark abdomen. Worker ants are blackish to reddish, and sizes vary from 2 mm to 6 mm (0.12 in to 0.24 in). Different size fire ants can exist in the same nest. A fire ant colony forms large mounds in open areas and will feed on young plants, seeds, and occasionally crickets. They often attack small animals and can kill them. Different from other ants which bite and then spray acid on the wound, fire ants bite to get a grip and then sting (from their abdomen) and inject toxic venom called solenopsin, a derivitive from the class of piperidines. For people, this is a very painful sting similar to a burn by fire—thus the name fire ant—and after effects can be deadly to sensitive individuals. The venom is insecticidal and antibiotic. They nest in the soil near moist areas such as river banks, pond shores, watered lawns and along highways. In most cases the nest will not be visible as it is built under timber, logs, rocks, or bricks. With no cover for nesting dome-shaped mounds will be visible, but these are usually found in open spaces such as fields, parks and lawns. Mounds can reach heights of 40 cm (15.7 in), and can be as deep as a meter and a half (five feet). Colonies are formed by small groups of queens or single queens. If only one queen survives, within a month or so, the colony can still expand to thousands of ants. Some colonies may be polygynous having multiple queens per nest.
Little Black Ants
Little black ants are very small black ants and are related to the Pharaoh ant (an indoor pest ant). Little black ants make their nests in soil under rocks, logs, or other debris and will build nests open areas of lawns. Nests in the ground are small craters of very fine soil. Little black ant colonies can also be found under bark of trees, in debris trapped in crotches of trees, damaged wood by termites, in piles of firewood and in stacks of bricks and stones. They feed on a variety of food including live and dead insects, and honeydew produced by aphids. Little black ants are active foragers and search in trails of a few or up to hundreds of workers. Trails can be located along sidewalks and foundations and up the sides of buildings.
Pharoah ants are also called "sugar ants" or "piss ants," and are some of the smallest ants, about 1/12-1/16 inch long, with a light tan to reddish body. Pharaoh ants are the most common indoor ant in Texas. Hospitals have found them to to be carriers of more than a dozen pathogenic bacterias including Staphylococcus, Salmonella, Pseudomonas and Clostridium. They do not sting and usually do not bite. Pharaoh ants are omnivorous, feeding on sweets (jelly, particularly mint apple jelly, sugar, honey, etc.), cakes and breads, and greasy or fatty foods (pies, butter, liver and bacon). Rarely will you find nests outdoors, but almost anywhere indoors (light sockets, potted plants, wall voids, attics, in any cracks and crevices) and close to sources of warmth and water. Development of worker ants evolves from an egg (5-6 days), to several larval stages (22-24 days), a prepupal stage (2 to 3 days), through a pupal stage (9-12 days) to an adult ant, taking from 38 to 45 days from egg to adult (4 days longer for sexual forms). One to several hundred queen ants, sterile female worker ants, periodically produced winged male and female reproductive ants (sexuals) and brood (developmental stages) make up a colony. Pharoah ants do not swarm. Pharoah ant colonies will multiply by "budding", where a large part of an existing colony migrates carrying brood to a new nest.
Crazy ants or Paratrechina longicornis (Latreille), occur in large numbers in houses or outdoors. This species will forage a long distance away from their nest which makes nests more difficult to control. Its name comes from its erratic and rapid movement and not following trails as other ants do. While the term "crazy ant" is identified with this species, there are other related ant species that are called "crazy ants." The crazy ant morphologically distinctive so that it is one of the few Paratrechina that is not misidentified in collections. The crazy ant worker is small (2.3-3 mm). The crazy ant head, thorax, petiole, and gaster are dark brown to blackish or reddish color. The body most likely will have a faint bluish iridescence. The antennae of the crazy ant have 12-segments with no club and are extremely long. The scape, the basal segment of the antenna, is extraordinarily long with the apex surpassing the posterior border of the head by at least one-half the scape length. They eyes that are elliptical, convex, and are close to the posterior border of the head. Crazy ants are highly adaptable and can live in very dry and very moist habitats. The crazy ant will nest some distance away from its foraging area. They will make nests in places such as trash, refuse, cavities in plants and trees, rotten wood, in soil under objects and also have been found under debris that remains by buildings for an extended period of time. Crazy ants will nest in a variety of locations from dry to moist environments. Crazy ant nests can be found by looking for workers carrying food back to the nest.