The temporary indoor, winter nest is usually somewhere in the basement under a loose brick or board or in a crack in the wall or floor. The ants do not forage for food through the house and apparently cause very little damage except to create piles of dirt at the entrance to the nest. Reportedly, these ants try to return to the outdoors sometime in the early spring if left undisturbed. Control of larger yellow ants is not critical, since they cause little damage other than the annoyance of their presence. Ants found indoors in the winter can be vacuumed or swept up and discarded.
Control outdoors is of little benefit.
Treating nest sites with a common lawn insecticide such as malathion, diazinon or Dursban can eliminate colonies. Use of one of these residual insecticides as a barrier on the foundation and yard adjacent to the house may reduce some accidental invasion. It may or may not apply in your area. Prepared by Donald Lewis , Extension Entomologist. Before reprinting this information, please read the usage policy .