Carpenter ants (Camponotus spp.) can be found nearly anywhere in North America. Although they don’t eat wood, they tunnel through it to create hollow areas for their nests. If they get indoors, they’ll begin at spots with moisture damage, but from there, they can get into stronger wood, eventually weakening it and causing serious structural damage.
We’ll show you how to identify and get rid of carpenter ants on your own. However, since it’s nearly impossible to see the extent of an infestation or its damage at first glance, we strongly suggest hiring a professional exterminator to treat a carpenter ant problem. In this article, we’ll also offer our recommendations for the best pest control companies in the United States that treat carpenter ants.
How to Identify Carpenter Ants
There are multiple carpenter ant species, and they vary by color and size. However, the most common carpenter ants in North America are very large, from one-quarter inch all the way up to five-eighths of an inch in length. They’re usually black or reddish, and some may have wings. These wings assist the ants in swarming to find a new location for a colony, which happens in the spring—May through August in the eastern U.S. and February through June in the west.
Because carpenter ants build nests in wood, winged carpenter ants are sometimes confused with termites. However, you can easily tell these two pests apart with the naked eye. Carpenter ants have a narrow “waist,” or middle body segment (thorax), and their antennae have an angle to them, like an elbow. If these ants have wings, there are few veins, and the front pair of wings are longer than the rear pair.
Termites, on the other hand, have veiny wings, all four of which are the same size. They have straight antennae (no “elbow”), only have two body segments, and their midsections are thicker.
Signs of a Carpenter Ant Infestation
You’ll likely see the worker ants before you find the nest. The appearance of a few carpenter ants inside your home doesn’t necessarily mean there’s a large colony indoors—it may be that a few ants have ventured inside from an outdoor colony. However, if you see a springtime swarm of winged carpenter ants, that means an established parent colony is nearby, as these swarms don’t emerge unless a colony has been around for at least two years.
Other signs you might see are small holes in the surface of wood where the ants have burrowed in. If the holes were made by carpenter ants, there will almost certainly be small piles of coarse sawdust (called frass) beneath the holes.
There may also be dead ants or ant body parts within the wood shavings. These ants most commonly nest in damp, decaying wood, so if you’re looking for a nest, look in areas near water leaks like in bathrooms, under sinks, or around windows and door frames.
Threats of Carpenter Ants
Where you live does matter—for example, the black carpenter ant that lives in the northern U.S. is more likely to make its home indoors than southern species. Fortunately, carpenter ants don’t pose a significant threat to your health, as they don’t spread disease, and while their bites can be painful, they’re not dangerous and they don’t bite often.
However, the threat they pose to the structure of your home can be significant. Since they hollow wood out to build their nests, if they get into the wall voids of your house and stay there undetected, they can cause catastrophic levels of damage.
The good news is that carpenter ants don’t do quite as much damage as termites, and they don’t work as quickly. Since they must leave the nest to find food, they’re also easier to spot. Nevertheless, once you spot the signs of a carpenter ant infestation, you need to act fast.
DIY Home Methods to Get Rid of Carpenter Ants
Because these insects live in hidden nests, it’s important that you don’t immediately start killing the first carpenter ants you see inside your home. The first step is to locate the nest so that you can destroy the colony.
Finding the Nest
As soon as you see carpenter ants in your home, follow them. As these ants walk, they lay down scent trails that allow other ants to follow them to and from food sources. You may need to be patient and follow them back to baseboards, cabinets, doors, or other wooden structures. You may even need to follow them outside if they’ve nested in tree stumps or dead trees.
However, even if you have an ant problem, you might not always see actual ants out and about. If this is the case, you may need to lure them out with some sweet bait, like diluted honey or sugar milk.
Carpenter ants are nocturnal, so set the bait out at night and then wait. When you get to the suspected area of the nest, listen closely—you may be able to hear a faint rustling sound. You can also tap on areas of suspected nests to listen for hollow sounds of damaged wood.
Killing the Ants
Once you’ve located the carpenter ant nest, you have several options for extermination.
The most common solution is to use an insecticide that contains pyrethroids. The trick is getting insecticidal spray or dust into the nest. You should never spray liquids around electrical outlets or junction boxes, but insecticidal dust can be used in these areas.
You can spray into any existing crevices, but you’ll probably need to drill additional holes into the voids in walls or hollow doors to access the colony. When using pesticides, always follow the instructions on the packaging. Also, only apply it to nests—killing individual worker ants won’t make a dent in the problem.
Boric acid dust also kills carpenter ants on contact, and it may be safer and easier to get into tiny spaces. Boric acid dust should be available at most hardware stores, and you’ll typically use an included applicator to puff the dust into holes or crevices.
Ant baiting is another possible solution, but it takes a bit longer to work. You simply apply the poisoned bait along the ants’ walking paths for them to pick up and bring back to the nest. There are special baits for carpenter ants, as generic ant baits might not be effective. Even so, ants can be picky, and if they ignore one type of bait, you may need to try another.
Desiccants are products that kill insects by destroying the outer protective layer of their bodies and causing them to dehydrate. Only licensed exterminators can apply silica gel, but diatomaceous earth is another common desiccant that anyone can purchase. It’s non-toxic to people and animals, but make sure not to breathe in any of the fine dust, which can cause lung damage. You can apply it into nests the same way you would an insecticidal dust.
Both diatomaceous earth and boric acid are non-pesticidal ant killers. If you do an internet search, you’ll find results claiming that all manner of essential oils or household products “repel” carpenter ants. Even if this is true, you don’t want a repellent at this stage of an infestation, as the ants will likely just relocate within your home or property, probably to a harder-to-treat location. You need to kill off the colony within your home before you concern yourself with repelling ants.
When to Call in the Pros
Unfortunately, because carpenter ants can nest deep within the structure of your home, they’re difficult to remove on your own. If you haven’t had any success with DIY methods, it’s better to call a professional exterminator sooner rather than later.
A pest control company will have access to better equipment and pesticidal products than most homeowners, and they’ll know how to access hidden nests while causing the least possible amount of structural damage to your home.
Our Top Picks for Professional Pest Control
Most professional exterminators should be able to take on a common pest like carpenter ants, but here are our top picks:
Terminix offers a premium ant plan for getting rid of carpenter ants, in which trained technicians will locate and treat the primary colony as well as any satellite colonies. For a free quote from Terminix, call 866-569-4035 or fill out this quick form.
With more than 400 locations across the country, Orkin is almost guaranteed to have a branch to serve you. With one of the company’s residential treatment plans, you’ll qualify for the Orkin Guarantee, a money-back offer that’s good for 30 days after treatment. For more information, enter your contact info or call 877-868-1416.
Although Bulwark isn’t available everywhere in the U.S., this family-owned company is now available in many major urban centers. Its technicians prioritize customer service and can perform either one-time carpenter ant treatments or regular pest control visits. Fill in your information or call 844-567-2094 for a free estimate from Bulwark.
Frequently Asked Questions About Carpenter Ants
How do I prevent carpenter ants?
Whether you’ve just treated an infestation or you want to avoid one in the first place, here are some tips for carpenter ant control and prevention.
- Keep food in tightly-sealed containers.
- Fix water leaks in or around your home to prevent wood damage that may offer a potential home to carpenter ants.
- Similarly, improve ventilation or use a dehumidifier in damp, enclosed areas of your home like crawl spaces or basements.
- Trim back any tree branches or other foliage that touches your siding or roof. Move wood piles, mulch, or mounds of soil away from the sides of your home.
- Seal holes or cracks around vents, pipes, or wires with caulk.
- Hire a professional to apply a perimeter treatment around your home or yard.
What’s the difference between termite damage and carpenter ant damage?
Termites produce a mud-like material as waste from eating wood, which they’ll leave behind in their nests; carpenter ants only leave behind wood shavings. Holes and tunnels created by termites have a rougher look, whereas those created by ants look smooth and polished. If you’re unsure, contact a pest control professional to perform an inspection.
What do carpenter ants eat?
As previously mentioned, carpenter ants don’t eat wood. Instead, they prefer honeydew, a sugary liquid secreted by aphids. In fact, carpenter ants actively “farm” nearby aphids for this food.
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