Harvester ants gather seeds and vegetation for their food, and are very unlikely to enter structures. However, they may be common in urban areas, and with their ability to sting and their large size they may become a problem. In addition, their activities can have a serious effect on agricultural crops or ornamental plantings. Nest openings are identified by the large, circular, flat area around them, created by the workers as they clear debris and soil from the underground chambers. This area averages 12 feet in diameter, and distinct paths lead from it to over 200 feet away for foraging. Nests may go as deep as 15 feet, with numerous chambers, and the population of workers may exceed 12,000. Swarming by reproductives occurs throughout the summer months.
Harvester ants are not known to forage or nest within structures, although their nests may be under slabs or porches around the exterior, and commonly in lawns and other urban areas. Treatment directly into the nest with a residual dust insecticide may be effective. They also appear to take granular baits readily, particularly those based on grain or cob grit, and these can be placed near nest entrances.