Carpenter Ants
As the name suggests these ants are masters at cutting, carving, and building structures in wood.
What do carpenter ants look like?
There are many species of carpenter ants, and distinguishing between them can be quite challenging. Because they belong to the same genus, they share similar physical traits, making it difficult to tell them apart without a trained eye. Adding to the complexity, carpenter ants are a polymorphic species, meaning their workers vary in size. This evolutionary adaptation allows for a highly specialized workforce within their complex colonies, with different-sized workers performing specific tasks. As a result, not only do multiple species closely resemble one another, but even ants within the same species can look a bit different.
Identifying carpenter ant species can be a daunting task considering:
60 species of carpenter ants can be found in North America
24 of those species are known to be nuisances, and a risk for causing damage to structures.
9 species of carpenter ants are native to Ontario

Fortunately, in Southwestern Ontario, identification is relatively straightforward, as we primarily encounter 2 species of carpenter ants in the region.
what are the most common carpenter ants in southwestern Ontario?

New York Carpenter ant
Pensylvannian Carpenter ant
Also known as red & black carpenter ant
Also known as the black carpenter ant
The most distinctive feature of the New York carpenter ant is its colouration, making it the easiest way to differentiate between these two species. Their thorax starts as a yellow-orange hue and gradually darkens to a reddish-brown over time. The legs and petiole share the same color as the thorax, while the rest of the body is black. Workers vary in size, ranging from 5-16mm, while queens can grow up to 18mm—making these some impressively large ants! Their abdomen is covered in small, upright white hairs and is connected to the thorax by a single node.
The Pennsylvania carpenter ant is entirely black, but its most distinctive feature is its impressive size. Workers typically measure between 5-8mm, while majors range from 10-17mm, and queens can grow as large as 16-20mm. They are one of the largest (and most widespread) carpenter ants in North America. Occasionally they appear to have stripes on their abdomen, but this is simply due to stretching when they are full of food or carrying eggs. Their abdomen is covered in long, upright hairs that are silver or yellow in colour, adding to their unique appearance.
The black carpenter ant is the one we experience most in Southwestern Ontario
Did you know?
The Pennsylvanian Carpenter ant was officially named in 1773, making in the first ant named in North America.
Where do carpenter ants nest?
Carpenter ants are drawn to wood - specifically softwood varieties and wood that is moist or decaying. This is because it’s easier for them to tunnel into soft, rotting wood than to penetrate healthy, hard wood. Their nests require humidity and stable temperatures, and when these conditions are met, they thrive. Outdoors, they typically nest in logs, stumps, dead tree trunks, or wood piles. When they invade homes, they often nest in wooden steps, windowsills, trim, attic spaces, and other wood. The presence of carpenter ants in your home can suggest a moisture issue or decaying wood in the structure.
Do carpenter ants eat wood?
It’s a common misconception that carpenter ants eat wood like termites do. Carpenter ants don’t consume wood; they chew through it to create tunnels for their nests. They actually feed on other insects, plant nectar, and plant juices when they’re nesting outdoors. Indoors, they prefer sugar, salt, fruits, meat, grease, fat, and even pet food! They’re particularly attracted to proteins and grease, so it’s not unusual to find them scavenging pet food or cleaning up grease spills. Carpenter ants can forage for food up to 100 meters from their nest, leaving chemical trails that guide other ants in their colony. Their ability to travel such distances increases the chances of them finding their way into our homes and structures.
Carpenter ant colonies
Carpenter ant colonies differ from other ant colonies due to their large populations and overall complexity. They have a parent colony, typically established outside within 100 meters of a building or structure. Parent nests require high humidity, moisture, and ideal temperatures to support the development of eggs and larvae. These nests house the queen, eggs, larvae, workers, and brood. Once the parent nest is well-established, satellite colonies are created nearby. Unlike parent nests, satellite colonies don’t require as much humidity or warmth. It’s at this stage that carpenter ants may begin nesting inside buildings. These satellite colonies house mature larvae, mature brood, and winged reproductive ants. Some colonies can have as many as 20 satellite nests, and depending on the species, a single colony can host up to 50,000 ants.
what are the Risks of having carpenter ants?
Carpenter ants are the most destructive ant species in Ontario and can cause significant damage to your home.
Ants are found in every natural setting; among the most destructive of them are the carpenter ants. They are the most efficient wood-destroying insects in North America and are the largest of our common ants.
- Natural Resources Canada
If left untreated, they will chew through any available wood—potentially compromising your entire home. The problem is worsened if there’s already damaged or decaying wood caused by leaks, as carpenter ants prefer weakened wood. They target these areas, tunneling through them to create their nests, further weakening the structure. Over time, they may move on to drier, stronger wood, hollowing it out and causing support beams to lose their integrity. This can lead to warping and serious structural damage.
Damage done by carpenter ants






This is why it is crucial to contact pest control professionals for treatment as soon as possible to prevent irreversible damage. Rural Routes Pest Control offers carpenter ant control, with options for one-time treatments or a year-long program.
for more information about our carpenter ant control services.
Signs that you have carpenter ants

finding small piles of sawdust
The most noticeable sign of carpenter ant activity is piles of fine sawdust. As they chew through wood to create their galleries (tunnels), they discard the wood shavings at the entrance. They regularly push this debris out of the tunnel, leaving clear evidence of their presence.


Faint rustling sounds
In severe infestations, you may hear a faint rustling sound coming from walls, floors, or woodwork. Carpenter ants have small hooks on their feet, which make a sound as they hook and unhook while walking. While a single ant’s movement is nearly impossible to hear, the collective movement of thousands of ants can create an audible rustling sound. As well, the sound of them chewing and excavating wood to create their galleries adds to the noise, making it more noticeable.


Winged ants in/around your home
Seeing flying ants inside or exiting your home is a clear sign of a thriving colony. Carpenter ants typically mate in late spring or early summer, which is when you'll notice the flying ants. Their presence indicates a healthy, thriving colony nearby, and it means they’re ready to establish new nests or colonies.


Have you noticed any of these signs?
If you have noticed any of these signs, then it is time to call in the pest control experts! Rural Routes Pest Control offers carpenter ant control, with options for one-time treatments or a year-long program.
for more information about our carpenter ant control services.