Question

I’ve been finding some large black ants in my kitchen. They seem to be coming in from under the garage door. From what I’ve seen on the Internet, they look like carpenter ants. Are they going to start a nest in my house?—W. P., Manchester, NH

Answer

There are at least two questions that need to be answered here. One, are they really carpenter ants, and two, are they just foraging into your home or could they have a secondary nest inside. These are both questions that should be answered by an exterminator.

It’s not uncommon for carpenter ants (or many other types of ants) to enter a home looking for food. Once they find a food source, like crumbs in your kitchen or a pet food bowl, it doesn’t take long for them to recruit other ants from the nest and form a regular trail to and from your kitchen. Ants that are foraging in from outside have a nest nearby in your yard in buried wood, old firewood, a dead tree stump, or similar site.

Carpenter Ants Look For Water-Damaged Wood

It’s also not uncommon for carpenter ants to have an established nest (or nests) inside a home. Carpenter ants prefer to nest in softened, water-damaged wood. Indoor infestations usually start in wood that is, or was, once wet from a plumbing leak, roof leak, or condensation. Sometimes the ants will then move into dry wood, and sometimes the ants will nest in small voids indoors and not in wood at all.

If your ants are coming in from outside, the chances that they will then establish an indoor nest in your house are slim. It would require a combination of just-right conditions and circumstances, including the presence of water-damaged wood. (See Finding the Source of Carpenter Ants)

If nothing else, you need some ant-proofing around your garage door to keep those foragers out. It’s rare to find a garage door that seals tightly at the corners and the bottom. You probably need a new door gasket, at the minimum. Our technicians can do that, too. Pest exclusion is one of the many services we offer as part of our total ant management package.

Give Colonial a call. Our trained technicians can give you peace of mind. They will identify your pest ants and conduct an inspection for ant nest sites, both outside and inside. Regardless of the type of ant, we can set up an ant baiting program and we’ll stay with you until you’re convinced that foraging ants are no longer a problem. Guaranteed!

Photo by Ingrid Taylar / CC BY