Ants feed upon every food consumed by man and are troublesome household pests. Some ant species feed predominantly on sweets, whereas others prefer meat and grease. Ants also act as scavengers and as predators of other insects.

Ants have chewing mouthparts, heavy mandibles suitable for biting, cutting and gnawing. The smallest ants are less than one-sixteenth of an inch long and the largest ant species attains a length of 1 1/2 inch.

When a newly mated female discards her wings, digs a nest and produces eggs, an ant colony is established. She nourishes the first brood through the larval stage. The larvae are translucent white, soft-bodied and legless. Larvae pass through several growth stages before pupation and adulthood. The young workers (foragers) will thereafter take over the work of the colony. Worker ants feed the queen, fight off enemies, construct a maze of tunnels, and care for the young. Most ant species have only one queen per nest. She lays the eggs, maintaining or increasing the colony size. When the colony has matured, a special brood of males and females is reared to establish new colonies. These winged adults are often mistaken for swarming termites.  

Ants are distinguished from termites by a narrow waist and bent or elbowed antennae. Termites have a broad waist and straight bead like antennae. The forewings of ants are larger than the hind wings and have comparatively few veins, whereas the two pairs of wings of termites are similar in size and appearance and have many indistinct veins.

Carpenter Ant (Camponotus spp.)
The carpenter ant occurs throughout the United States and is one of the largest common ants. The adults vary in length from one-fourth inch for small workers to three-fourths inch for a queen. The body is dark brown to black in color.

Carpenter ants seek soft, moist wood to establish their nests—particularly wood that has weathered and begun to decay. Although the nest is usually started in soft wood, the ants may later excavate into perfectly sound, dry lumber, for example, in porch columns and roofs, window sills, hollow core doors, firewood and telephone poles.

Carpenter ants do not eat wood (as is the case with termites), but excavate galleries in the wood in which to rear their young. These are made without regard for the grain and follow the softer portions of the wood. The galleries are kept smooth and clean, having a sandpapered appearance. Carpenter ants eject a coarse sawdust from the galleries; these characteristic sawdust piles indicate the nest’s location.

When carpenter ants are found within a structure, the colony is either nesting within the building or the ants are nesting outside and entering as they forage for food. Houses near wooded areas are especially subject to invasion. These ants feed on a wide variety of things including honeydew excreted by aphids, other insects, animal remains and household food scraps.

The key to the control of carpenter ants is locating the nest and often, doing so is the most difficult part. If the nest can be found, there is an excellent chance of controlling this pest.

Carpenter ants usually are found associated with moist conditions. When looking for the nest, carefully inspect any wood affected by water seepage (porch floors, roofs, porch posts and columns), In the area nearby, look for stumps, logs and trees that might contain nests. Trees with overhanging branches touching the roof may offer a colony direct access to the structure.

Sanitation measures such as removing and destroying logs and stumps that harbor nests are non-chemical ways to help prevent these pests. Replace any damaged or weathered wood.

For effective control, it is necessary to apply an insecticide directly to the nesting area. Use of a 5% carbaryl (Sevin) dust forced into the nesting site is generally the referred treatment. Spraying around the infested area with sprays of 0.5% diazinon, 1% propoxur (Baygon), or 0.5% chlorpyrifos (Dursban) and repeated as necessary should reduce the infestation, and may, depending upon circumstances, provide control.

Control of Nuisance Ants
Most nuisance ants nest outdoors. When foraging, ants may enter homes initially by chance. Household infestations often can be traced to the lawn, so treating the lawn often solves the problem. In these cases, a chemical barrier is a temporary but effective treatment if applied around the outside of the house. It is helpful to locate where the ants are entering the building or at least the direction from which they approach the area, Once the route is known, careful spot treatments with the proper pesticide will reduce the problem considerably. Treat all points of entry.

Mound-building ants build nests in the ground and form hills around the nest opening. The unsightly mounds may be difficult to mow over and sometimes smother a portion of the surrounding grass, In addition, some ant species weaken grass stands by destroying grass seeds and roots.

The following insecticides are labeled for ants on turf grass: diazinon (25°/0 emulsified concentrate [EC], 5% granule [G]); Dursban (chlorpyrifos) usually a 4 to 6% EC; malathion; and Sevin (carbaryl). Some formulations of Dursban are labeled for use by commercial and professional applicators only. Mowing the lawn before treatment exposes more of the mounds and minimizes the need to enter the treated area any sooner than necessary. Apply the spray or granules to the ant hills and then water the area thoroughly. Keep pets and people away from the area until the grass has dried.

An important aspect of ant centrol inside buildings is sanitation. Crumbs, grease, food scraps and foods in open or partly open containers are easily found by foraging worker ants and then attract large numbers of ants. Where good sanitation is practiced, heavy infestations in buildings are rarely found. Insecticides can reduce ant populations indoors, but they seldom are effective in eliminating colonies unless the nest is treated. Chemicals labeled for use indoors include diazinon, Dursban (chlorpyrifos), or Baygon (propoxur).

These should be purchased as ready-to-use formulations for indoor use, (See carpenter ants for strength of formulations) Outdoors, use of a concentrate to prepare your own spray will generally be more economical. Many lawn and ornamental preparations are also registered for ant control, Treating the trails that ants follow will, often discourage further entry. Otherwise, follow trails back to outdoor nesting sites, and treat nests by Iiberal use of one of the above mentioned insecticides. At times ants may be found nesting under concrete slabs, and may require the services of a professional pest control operator.