The most important step is identifying the ant species and determining where they are nesting. Treating outside will help control ants foraging inside from outdoor colonies. Find the nest first before applying a pesticide. If the ants are nesting in a wall, a perimeter treatment may act as a repellent and keep ants indoors. For ants nesting in walls, a contact insecticide should be used and it may require assistace from a professional pest control operator. Trails of foraging ants can be sprayed with a contact insecticide, but these treatments do not directly affect the colony. Make sure the product you select is labeled for use indoors. Read and follow the directions on the product label for best results. Be sure to keep products away from small children and pets.
For more information see,
Management Options of Fire Ants for Homes and Buildings
