Carpenter ant in Bellingham: how to tell it apart

This carpenter ant turned up on the floor of a Bellingham home. We confirmed it by two key features: an evenly rounded (convex) back when seen from the side, and a single node, the small bump in the narrow waist between the middle and the rear.

Carpenter ants are some of the biggest ants you'll see in Whatcom County, often 1/4 to 1/2 inch long. They're usually black, or black with dark red, with bent antennae and big heads on the workers. Winged swarmers show up indoors in spring.

They don't eat wood like termites do. They chew it out to build smooth tunnels and nests, pushing out piles of fine sawdust called frass, often mixed with insect parts. They love wood that's already damp or soft, around leaky windows, roofs, decks, bathrooms and crawlspaces, but they can spread into sound wood over time.

Left alone, a colony can keep growing for years and weaken framing, sill plates and trim. One ant inside often means a nest in the walls, with the main colony outside in a stump, tree or woodpile.

Seeing big black ants or little sawdust piles? Call or text Gavin.