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What Does Carpenter Ant Damage Look Like?

Most of the time, you're not going to see carpenter ant damage. These ants chew galleries inside areas of wood and use those galleries to establish their nests. And since it is impractical to leave their tunnels open and allow predators to get in and attack their nests, these ants try to avoid breaching tunnel walls. This makes it difficult to detect carpenter ants when they invade the wood of our homes. It does happen, though. Here are some places you can look for carpenter ant damage and what that damage may look like:


Carpenter ants love infesting fence posts, especially if those fence posts are in moist soil, and even more if they are old, unpainted, and untreated. If they attack your fence posts, you might be able to see damage close to the soil. This damage will look like someone used a carving knife on the wood and the trenches will feel smooth to the touch, almost like they’ve been sanded down.

Dying trees makes a good home for carpenter ants. If you have a nest in a tree on your property, you're likely to see a lot of big, black ants crawling around on it. And though you may think nothing of seeing ants crawling around on a tree in your yard, it is important to take note that you have carpenter ants on your property and that they pose a threat to your home. In addition, if you want to look into their galleries, you may be able to peel some bark off the trees they are infesting and find holes. It depends on where the infestation is located. Higher infestations, such as those inside an area where a limb has been chopped off the tree, may be harder to get to.

Stumps are another popular location for carpenter ants to establish their nests. If you have a stump with large cracks in it, you may be able to look into those cracks and see into the carpenter ants tunnels. But a few chops of an ax will expose those tunnels much faster and make them much easier to see. Those exposed tunnels will be stacked on top of each other.


If carpenter ants find their way into your home, they will gravitate toward cool, moist areas. A frequent target is window and door frames as these areas are notorious for having high moisture levels. If you have carpenter ants inside your door or window frames, you may see cracking, bubbling, dents, or tiny holes that are about the size of those carpenter ants. If there are kick-out holes, there is also likely to be frass underneath those holes. Frass is a sawdust-like material created by carpenter ants as they tunnel through wood.

Carpenter ants are also prone to tunneling into water-damaged sills that are located just above your cement foundation walls. You may be able to see some holes and frass clinging to the walls below those holes or frass coming out of the gaps in those sills if you inspect exposed sills in your basement. If you're unable to see the sills inside your basement, and your home has a crawl space, that is another good place to look for carpenter ant activity.


Though there are rare circumstances that carpenter ant damages are visible, most of the time, you're not going to see them at all. When carpenter ants get into a home, they often stay inside wall studs and push frass out into wall voids, where it can't be seen. So it is important to be on the lookout for the signs of carpenter ant activity.

  • Big black ants crawling around outside your home should not be ignored. Have those ants checked out and find out where they're coming from.

  • A single black ant walking around inside your home can be an indication that you have an infestation. And don't assume that just because you're not finding ants in your home you don't have an infestation. Carpenter ants create their nests in our homes and find food resources outside where you’re less likely to notice them.

  • If you find large flying black ants inside or outside of your home, it is time to call a pest control company. These are a sign of a well-developed nest on or inside your property!

  • Where there is frass, there are carpenter ants. If you're seeing frass but no ants, let that frass be your warning that you have a carpenter ant problem.

Over time, carpenter ants can cause a lot of damage. They attack water-damaged and rotting wood first for maximum damage but are able to move on to sound timbers within your home as well. Reach out to a pest control professional as soon as you see carpenter ant activity or signs of a carpenter ant infestation to avoid further infestation and costly home repairs!

For assistance with carpenter ant control in Missouri, go here for trusted pest control advice and service from the professionals at Rottler Pest & Lawn Solutions!


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