Pavement ants get their name because they often nest under sidewalks, driveways and building foundations. A mound of displaced soil along a paved area is probably a sign of pavement ant activity. During winters in the Kansas City area, pavement ants may nest inside structures near a heat source. They may also nest in the cracks of pavement or against building foundations.
Pavement ant workers vary in color from red brown to blackish-brown in appearance and are from 1/8. to 1/4. in length. They are black-brown ants, with paler legs and antennae. The abdomen is all black. They are distinguished by two spines on the back, two nodes on the petiole, and grooves on the head and thorax. The colonies can be moderately large. In the Kansas City area, swarmers usually appear in June or July. However, they have been reported at other times of the year. Six to eight weeks are required for development . The time varies because of the season of the year, the temperature, and the species. Colonies have three distinct castes: queens, kings, and workers. The only function of the queen and king is to reproduce. All of the workers are sterile females. The workers build the nest, take care of the young, and hunt for and gather food. The workers are the ones that you find invading a home looking for resources.
Pavement ants are trailing ants and feed on a wide variety of foods including dead insects, greasy foods, seeds and sweets, including the honeydew of aphids. Occasionally they may be found in walls, under floors, and in insulation. If your home is a slab-on-grade construction, pavement ant foragers enter through cracks in slabs or other openings. They often enter buildings through expansion joints in slabs. They move in small motions and their trails are most easily spotted at night. Look at plumbing pipes and electrical wires for their trails. During the spring, they are highly aggressive against other species of ants.
Control of Pharaoh ants is difficult, due to their nesting in inaccessible areas. Another reason for difficulty is that colonies have multiple queens. Treatment must be thorough and complete at all nesting sites, as well as the foraging area. Thus, treatment must include walls, ceilings, floor voids, and electrical wall outlets. Baits are now the preferred method of control for Pharaoh ants and several baits (insecticides) are labeled for indoor ant control. A Pharaoh ant infestation of a multifamily building requires treatment of the entire building to control the infestation. Ants nesting on the outside may be controlled by also using a perimeter barrier treatment.
Baiting is the preferred treatment over typical residual spraying. Baiting is the most reliable way to eliminate the entire colony. When choosing ant baits, it is best to choose from both the sugar-based baits and protein/grease-based baits. If using a spray, choose a non-repellent type unless you are treating the nest itself.