Once located, carpenter ant nests are distinguished from other insect damage by the presence of wide, irregular galleries that are smooth-surfaced and free of debris. Nests in houses may be satellites of larger outdoor nests that also need to be destroyed to avoid reinfestation. Extensively damaged wood may have to be replaced. If not, the nest and ant trails can be treated with an insecticide. Dust formulations are the most effective for carpenter ant control, as foraging workers become covered with the dust and carry it into the nest.
Sprayable formulations are effective under some conditions.
Several active ingredients are available. Nontoxic dusts that kill Insects by causing them to dry out also can be effective in certain situations. Poison ant baits have not worked well with carpenter ants. As with any insecticide, read and follow all label instructions. Trim shrubbery and trees away from the house.