Homeowners can recognize a carpenter ant from its large size (about a half inch) and dark color, from deep red or brown to black. They are so named because they typically build their nests in wood by hollowing out portions of a branch, landscape tie, deck board, or house framing. As such, they can be extremely destructive and cause severe structural damage in an infested building.
Carpenter ant colonies can number in the thousands as they occupy their chosen place over several years. The most significant sign of an infestation is seeing large numbers in or around your home. Nests often start in rotting wood outside of your home, but signs they have moved indoors may be wood shavings or sawdust around wood trim and windowsills.
Reduce your risk of a carpenter ant infestation by clearing your yard of shrub and tree debris and limiting the use of wood mulch. Avoid storing firewood near or against your house.