A few large black ants wandering across the kitchen counter at night is easy to brush off. The trouble is that carpenter ants don't really forage at random. When they show up indoors regularly, there is usually a nest in or against your home, carved into wood that water got to first. Left alone, they widen those galleries season after season. Catching them early and fixing what attracted them keeps a minor nuisance from becoming real damage.
Quick answer
Carpenter ants don't eat wood, but they hollow it out to nest, and they almost always pick wood that has been softened by moisture. If you see large black ants indoors, especially at night, plus little piles of sawdust-like shavings, you likely have a nest nearby. The fix is finding and treating the nest, then correcting the moisture that drew them in. Spraying the ants you see rarely solves it.
Dealing with this right now?
Seeing big black ants and little piles of shavings around your home? Schedule a carpenter ant treatment with Kingwood Pest & Termite. We'll track down the nest, clear the colony, and flag the moisture issues that drew them in.
Learn more about our ant control across Spring, Kingwood, and North Houston.
How to Know You Have Carpenter Ants
Carpenter ants are among the largest ants you'll see indoors, usually a quarter to half an inch long, and most around here are black or very dark. They're most active after dark, so a flashlight tour of the kitchen and bathrooms an hour after sunset often turns up more of them than you'd guess.
The telltale sign is frass: a fine, sawdust-like material the ants push out of their galleries as they excavate. It often contains bits of insulation and insect parts and collects in small cones below the nest, behind appliances, along baseboards, or under a window. Faint rustling inside a wall void is another clue once a colony gets going.
Carpenter Ants Versus Termites
People mix these two up constantly, and it matters because the treatment is different. Both can produce winged swarmers, but the bodies don't match. Carpenter ants have a pinched waist, bent antennae, and front wings longer than the rear pair. Termite swarmers have a straight waist, straight antennae, and four equal wings.
The damage looks different too. Carpenter ants leave clean, smooth galleries and push frass out, so you see those shavings. Termites pack their tunnels with mud and don't produce sawdust. If you're not sure which one you're dealing with, save a couple of the insects and any debris so a technician can confirm it.
Why They Picked Your Home
Carpenter ants chase moisture. They almost always start in wood that has been dampened by a leak, poor drainage, or condensation, because soft wood is easy to tunnel. In our humid climate, that gives them plenty of options.
Common starting points are around leaky windows and door frames, under sinks, behind dishwashers, in soffits fed by clogged gutters, in damp crawl spaces, and inside old tree stumps or firewood stacked against the house. They'll also trail in from a nest outdoors to forage for the sweets and proteins in your kitchen. Tree limbs touching the roof give them a convenient bridge.
- Leaky window frames, door frames, and plumbing
- Damp wood behind dishwashers and under sinks
- Soffits and fascia soaked by clogged gutters
- Firewood, stumps, and mulch piled near the foundation
- Tree branches touching the roof or siding
Steps You Can Take Now
Start by cutting off what draws them. Fix the leaks and improve drainage so the wood dries out, since damp wood is the whole reason they're there. Trim back branches touching the house, move firewood away from the foundation, and pull mulch back from the siding.
Keep counters wiped, seal sweet and greasy foods, and take out crumbs and trash, which removes the food that keeps foragers coming. Caulk obvious gaps around pipes, windows, and the foundation. These steps make your home far less attractive, but on their own they often don't reach the nest, which can sit deep in a wall void or in a satellite colony you'll never spot.
When to Bring in a Professional
Carpenter ants are stubborn for a reason: a colony often has a main nest plus satellite nests, sometimes one outdoors and one inside the same house. Spraying the trail kills the foragers you see while the queen and the rest keep producing more. That is why store-bought sprays so often seem to work for a week, then the ants are back.
A professional treatment finds where the nest actually lives, follows the trails back to it, and uses targeted baits and applications that the ants carry into the colony so the whole population goes down. We also point out the moisture and entry issues that invited them, so once the nest is gone, the next colony doesn't simply move in. For active carpenter ants in the Kingwood and Spring area, that combination is what finally ends it.