How to Get Rid of Carpenter Ants, According to Entomologists

You might think that a tiny ant couldn’t possibly ruin your day, let alone your home. But when it comes to carpenter ants, these industrious little organisms can do some serious damage. Carpenter ants encompass several species of the genus Campnotus, a group of wood-destroying organisms (WDOs) whose common name comes from their ability to construct complex nests in wood.

Carpenter ants can prove to be a major problem if they decide to make their home in your home, as their penchant for burrowing tunnels means they weaken that part of your property's structure. If you think you have these insects as unwelcome houseguests, read on to learn how to get rid of carpenter ants, according to entomologists.

What Carpenter Ants Look Like

Carpenter ants are fairly large, as far as ants go. They’re usually visibly larger than common black garden ants, though they vary in size depending on their role in the colony. They can be anywhere from 1/3 inch to 5/8 inch long, says Jim Fredericks, board-certified entomologist and senior vice president of public affairs at the NPMA. “While black carpenter ants are common, you may also find a combination of black and red, red, or brown.”

Like all ants, carpenter ants have a hard exoskeleton, dark coloration, and tend to be seen during an infestation when they forage outside their nests for food, says Emma Grace Crumbley, an entomologist with Mosquito Squad.

Carpenter Ants vs. Termites

Carpenter ants are often confused for termites due to their similar wood-destroying habits, but they have distinct differences.

Appearance

In terms of appearance, ants, bees, and wasps are all classified in the same order (Hymenoptera), with a key feature being their "snatched" wasp waist, says Crumbley. "This waist is the fastest way to tell the difference between a winged termite and a winged ant," she says. Termites have broad black bodies without a defined waist.

Diet

While both pests chew through wood, what they do with it differs. “Carpenter ants do not eat the wood they tunnel through,” says Crumbley. “Since they don't consume the wood, carpenter ants will design kick-out holes to dispel debris. This, combined with their galleries' smooth, sanded texture, makes carpenter ant damage much cleaner than termite damage.” 

Unlike ants, termites eat wood for its cellulose content, which they need in order to survive. “Termites are blind, and when they chew through wood, they eat through the soft wood path as opposed to the harder wood separating the grain,” says Crumbley. This leaves linear tunnels in line with the wood grain, whereas carpenter ants' damage can cut across the wood grain. 

Habitat

Carpenter ants and termites may also choose different parts of your home to invade. Termites typically cause damage in either the lowest parts of the structure (for subterranean termites) or the highest parts of the structure (drywood termites), says Crumbley. Check your attic and basement if you think you have a termite infestation.

Carpenter ants are more versatile. “Interior carpenter ant nests may be found in walls, windowsills, baseboards, fireplaces, and other spaces with hollow areas. Exterior nests may be found in nearby trees, telephone poles, mailboxes, tree stumps, and woodpiles," says Crumbley.

Causes of Carpenter Ants

Carpenter ants are drawn to the basics they need to survive: water and food. “Carpenter ants require a water source to survive, so moist or decayed wood will provide an ideal environment for nesting,” says Fredericks. “They are often attracted to wood softened by water damage, so homes with leaks, poor ventilation, or wood in contact with soil are at higher risk.” 

Carpenter ants also require a food source, which may be inside or outside your home. “The presence of accessible food sources, like insect honeydew, plant and fruit juices, insects, and other arthropods, can draw them in,” says Fredericks.

Signs of Carpenter Ants 

There are a few telltale signs you have a carpenter ant infestation in your home.

Seeing Carpenter Ants

One of the most obvious signs of a carpenter ant infestation is seeing these pests around your home. “If you see a pest, you have a pest," says Crumbley. You may be more likely to see a carpenter ant out and about at night, as that’s when they tend to forage for food, but on occasion you may also spot one during the day.

Wood Damage

Wood damage is another sign you have carpenter ants. Much of it is unseen as it’s within the wood of a home, but look for “kick-out holes.” These are places where the ants remove the debris to create by their tunnels. They appear as small holes with piles of sawdust-like shavings, pieces of insulation, or insect body parts. 

Hearing Carpenter Ants

In extreme cases, you may even be able to hear the ants moving about and tunneling in the walls of your home. If you do, Crumbley recommends marking the area where you hear the noise so you can point it out to pest control professionals and see if it spreads.

How to Get Rid of Carpenter Ants 

The best way to get rid of carpenter ants is to locate the nest and either physically remove it or treat it with an insecticide. Once you've found the nest, you can apply dust or aerosol formulations designed to treat carpenter ant infestations. When using dust, apply a small amount into voids where the ants are known to be nesting and in voids they use when foraging.

Dust formulations of diatomaceous earth, silica aerogel, or boric acid are all examples of safe solutions that have no or low toxicity to mammals and can be blown into nests and cavities to kill the ants. If you can't locate the nest, apply the dust in areas where you suspect carpenter ants are hiding.

That said, locating the nest is much easier said than done, and our experts say that best way to get rid of carpenter ants is to call a pest control professional for assistance. If you think you have carpenter ants, there are some things you can do to prepare for a pest control professional, though. 

• Mark the area where you’ve seen or heard evidence of carpenter ants.
• Monitor the area and note any changes.
• Keep the area clean and dry so as not to encourage more ants.
• Seal off entry points to make it more difficult for ants to get back into your home. Identifying entry points can also help the exterminator locate the nest.
• If you see an ant, take a photo of it to verify with a professional.
• If you hear noises in the walls, record a video to show the PCP as well.

How to Prevent Carpenter Ants From Coming Back 

Prevention is key in reducing the impact of carpenter ants in your home.

• Fix decaying wood: Because carpenter ants are drawn to moist or decaying wood, check your home regularly for damp areas or signs of rotted wood and repair them immediately.
• Check basement and crawl space: Pay special attention to spots along the exterior of your home, including basements and crawl spaces that have direct contact with the ground or are accessible from the outside.
• Repair leaks: Fix any leaks immediately before they damage the surrounding wood, and make sure all areas of your home are properly ventilated so moisture doesn’t build up.
• Seal entry points: Look for ways carpenter ants might access your home and eliminate them. Seal up any holes or cracks along the outer walls, doors, and windows of your home.
• Cut back branches: Cut away tree branches or other plant growth that touches your home, as carpenter ants can use these as a bridge to get into your roof.
• Keep wood away from your home: Keep other wooden materials like firewood, building supplies, or wooden outbuildings away from your house.
• Use pressure-treated wood: Using pressure-treated wood for outdoor wooden structures like decks can also help deter carpenter ants.

When to Call a Professional

When it comes to enlisting professional help, the sooner the better. Carpenter ant infestations are tricky problems that benefit greatly from the expertise of professional pest control experts. If you notice signs of carpenter ants, document the evidence and contact a pest control professional in your area who can provide an assessment of the damage, effectively treat it, and give you advice on how to prevent future infestations.