Outdoors, pavement ants are ground-nesting ants. In nature they nest under rocks and logs. In residential neighborhoods they make nests under sidewalks, driveways, and slabs of homes. They enter homes through cracks in walls and foundations.
When pavement ants move indoors, they often nest inside of walls. In cold weather they have been found nesting near water heaters and furnaces. The workers forage for food in trails that can extend 25 or 30 feet from the nest.
If pavement ants are becoming a problem, start by following the trail of workers. It is often possible to follow the trail back to the nest. If the trail leads outdoors, it may be possible to drench the nest with liquid insecticide and eliminate the colony. Follow the label directions for mixing and applying insecticide.
If the trail leads under a baseboard, it may be possible to drill tiny holes above the baseboard. Inject insecticide dust into the void inside the wall. Products that contain boric acid or diatomaceous earth may be slower acting than other products, but they will last the longest.
Ant bait is a very effective tool against pavement ants. Liquid or gel bait will be accepted quickly. Place the bait near the trail so the workers will find it. Make sure children and pets cannot reach the bait. Keep the bait station filled with fresh bait until all the ant activity has stopped.
An insecticide barrier around the outside perimeter of the home can help prevent pavement ants from invading the home. Because of sunshine and rain, the barrier will have to be re-applied periodically. Ant control takes time and requires patience. Many homeowners find it easier to let a pest control professional take care of these pests.