Ants are among the most prevalent pests in households. They are also found in restaurants, hospitals, offices, warehouses, and other buildings where they can find food and water. On outdoor (and sometimes indoor) plants, ants protect and care for honeydew-producing insects such as aphids, soft scales, whiteflies, and mealybugs, increasing damage from these pests.
Ants also perform many useful functions in the environment, such as feeding on other pests (e.g., fleas, caterpillars, termites), dead insects, and decomposing tissue from dead animals. Inside buildings, household ants feed on sugars, syrups, honey, fruit juice, fats, and meat. Long trails of thousands of ants may lead from nests to food sources, causing considerable concern among building occupants.
Ants build many different types of homes. Many ants build simple little mounds out of dirt or sand. Other ants use small sticks mixed with dirt and sand to make a stronger mound that offers protection from rain. Western Harvester ants make a small mound on top, but then tunnel as deeply as 15 feet straight down to hibernate during winter. Ant mounds consist of many chambers connected by tunnels. Different chambers are used for nurseries, food storage, and resting places for the worker ants. Some ants live in wood like termites. Army ants don’t make a home at all but travel in large groups searching for food.
There are over 12,000 species of ants throughout the world. In the United States there are about 200 species but fewer than a dozen are important to us as pests. One of the most common house/garden ants is the Argentine ant (Linepithema humile). Other common ant pests include the pharaoh ant (Monomorium pharaonis), the odorous house ant (Tapinoma sessile), the thief ant (Solenopsis molesta), and the southern fire ant (Solenopsis xyloni). The velvety tree ant (Liometopum occidentale) nests in old wood and is a common outdoor species in landscapes.
Of great importance is the red imported fire ant (Solenopsis invicta) which has recently seen a population increase throughout the southern United States. In some areas, its spread has been slowed by competition from the Argentine ant. Carpenter ants (Camponotus spp.) also invade buildings all over America. Although they do not eat wood like termites do, they hollow it out to nest and can cause considerable damage.
