Insect · High risk
Carpenter Ant
The carpenter ant does not eat wood: it hollows it out to house its colony. The galleries spread year after year through damp or decaying wood, and the main nest is often outside, in a stump or a tree. Targeting the nest is the only lasting solution.
Worker 6 to 13 mm · Black to brown
§1Distinctive features
How to identify it
At 6 to 13 mm, the carpenter ant is one of the largest ants in Quebec. Mostly black, sometimes brownish or with reddish tints, it stands out by its evenly rounded thorax seen from the side and its petiole with a single node. Six species are recorded in Quebec, including Camponotus pennsylvanicus and Camponotus novaeboracensis, the two most often found in buildings. Winged queens can reach 20 mm.
§2Habitat
Where to find it
It settles in damp or decaying wood: old stumps and dead trees, but also door sills, joists and window frames. A satellite nest, which mostly holds older larvae and pupae, can form inside the house within about a hundred metres of the main nest, which stays outdoors.
§3Reproduction
Lifecycle
A colony takes 3 to 6 years to mature, but it keeps digging the whole time.
§4What to look out for
Signs of infestation
- Wood shavings (frass) mixed with insect parts, near baseboards
- Swarm of winged ants indoors, in spring
- Ants seen inside the house at night
- Faint rustling inside walls or the ceiling at night
- Visible damage to wooden structures
§5Why act fast
Risks
- Galleries spreading through damp wood in the house
- A colony reaches 2,000 workers in 3 to 6 years
- The galleries follow moisture and reveal a water problem
- Hard to eliminate without a targeted professional treatment
§6Prevention
How to avoid it
- Avoid stacking firewood against the house
- Remove rotting stumps close to the house
- Seal cracks around windows and doors
- Control water leaks and moisture
- Trim branches that touch the building
- Store food in airtight containers
§7Pro method
How MW works
Inspection
Inspection of the building and locating sources of moisture.
Preparation
Customized plan · steps to take before the visit.
Treatment
Locating the main nest and satellite nests, treatment with non-repellent baits.
Follow-up
Control visit · written guarantee offered depending on the treatment chosen.
§8Your questions answered
Frequently asked questions
Do carpenter ants eat wood?
No. They dig into wood to house the colony and push the shavings out of the galleries. Unlike termites, which digest wood, the damage progresses much more slowly. A colony that has been living in damp framing for years is still costly to repair.
How can I tell it from an ordinary black ant?
The carpenter ant is much larger, 6 to 13 mm, with an evenly rounded thorax seen from the side and a petiole with a single node. Do not confuse it with a winged termite, which has straight, beaded antennae, a body with no narrow waist and four wings of equal size.
Should I call a professional?
Yes. They are very hard to eliminate without a treatment that targets the nest at the source.
The carpenter ant digs into wood to house its colony, which makes it the pest that most directly affects the structure of a building. Our carpenter ant treatment targets the main nest and the satellite nests. Older buildings in Sherbrooke and the wooded areas around Granby, Magog and Bromont are particularly exposed.
Sources consulted for this fact sheet: Health Canada, carpenter ants · Natural Resources Canada, carpenter ant · Espace pour la vie, carpenter ants · Entomofaune du Québec, genus Camponotus.
React quickly, sleep well.
The longer the infestation lasts, the more expensive it becomes.