[Ant Control Issue] Carpenter Ants Everywhere

A dozen species of carpenter ants — six in Eastern provinces and six out West — will make their presence known to homeowners across Canada this spring.

To help pest management professionals prep for the season, carpenter ant authority Dr. Laurel Hansen of Spokane Falls Community College in Spokane, Wash., offered these reminders for PMPs in Canada and the United States:
 

Nesting Behavior: Carpenter ants in the East generally have smaller parent nests in deciduous trees, while Western species prefer conifers and larger nests.
 

Satellites in Structures: Carpenter ants are attracted to the soft, easy-to-chew wood used to build most houses, making structures ideal for satellite colonies. These usually are found in the attic, crawl space or subfloor where ants have access to the outside. The presence of winged ants indoors in early spring is a good indication that the structure has a satellite colony.

Workers Move In: All workers come from the parent colony. They move into the satellite colony in summer and, once established, may stay there for a long period. The satellite colony must have worker reinforcements from the parent colony or it will die out.

Reproductives Move Out: Satellite colonies commonly contain winged male and female reproductives. These ants do not add to the satellite colony population; they will fly off to start the next colony. Satellite colonies usually do not contain a queen and do not reproduce unless workers are reproducing males.

Food Preferences: Carpenter ants don’t eat wood, they nest in it. They are omnivores, feasting on caterpillars, honeydew and their favorite — aphids and other hemopterans. Occasionally, warm indoor temperatures will interrupt the ants’ winter dormancy, and homeowners will find them seeking moisture in sinks or getting an early spring sugar fix on donuts or fruit.

Vegetation Must Go: Carpenter ants must go outside to feed, so PMPs should inspect vegetation and ensure none touches the structure. This includes branches that may scrape the roof during heavy snow or rain. “My rule of thumb is nothing touches the structure, as far as vegetation is concerned,” Hansen said.

Check the Wires: The ants also will walk wires into structures, so carefully inspect cable/Internet lines. Some lines go through trees, making for a perfect way in and out.

Keep Wood Dry: Moisture weakens wood siding — which, in turn, attracts ants — so take steps to keep it dry. Grade the foundation so water runs away from the structure, and keep the area clear so snow build up and splashing rain won’t compromise the siding. Never let wood come in contact with the soil.

Pay Attention to Birds: Woodpeckers drum in the spring to call for mates, but they also peck holes in houses to get to carpenter ants — a chief food source. If a homeowner has woodpecker issues year round, consider removing the siding in key spots: You may uncover an ant problem.

Get the History: Buried wood is highly conducive to carpenter ants, so interview clients about their yards. Are stumps or timbers buried on the property? What’s under the bark and landscape plastic in the flower beds? They may not know but it’s worth asking.

Know Your Ants: PMPs must be able to separate carpenter ants from other ants around the structure. The big majors and winged females are easy to identify, but smaller species are more difficult. In British Columbia, for instance, the wood-destroying velvety tree ant is becoming a problem in structures.
 

Editor’s note: This article originally appeared in the Pest Control Canada e-newsletter, sponsored by Univar PP&S. To receive this e-newsletter, e-mail jdorsch@giemedia.com with the subject line: “Subscribe Canada.”