Treating carpenter ants Begin by trying to locate the nest. This is easier said than done, but the effort pays off. Look at both indoor and outdoor sites, and look at night when foragers are most active. Look for ant trails or a general direction of movement or feed foragers small dabs of honey and then follow them to the nest. If necessary replace damaged or decayed wood at the infestation site and correct moisture problems.
Homeowners can treat with 'ant and roach killer' insecticide sprays or boric acid dust.
Treat wall voids and other hidden spaces where ants are entering by spraying the liquids or puffing the dust into cracks and gaps or through small drilled holes if necessary. If you can not locate the nest, make a general application of spray or dust to cracks, crevices and room edges where ants are most numerous. Dust can be injected into wall voids via the holes surrounding electrical outlets. Use extreme caution around electrical wiring. Spraying outlet openings is not recommended.