Carpenter bees are mostly solitary bees that build nests by tunnelling into wood. Though somewhat rare in Winnipeg and the surrounding area compared to honeybees and bumblebees, they fill an essential role as pollinators.
While carpenter bees are considered beneficial insects in the natural environment, they build tunnels into almost any kind of wood—not just trees. Carpenter bees may decide to build a nest in wooden structures around your home; when they do so, they can cause serious structural damage.
Carpenter bees can be difficult to identify to the untrained eye. Their thorax is yellow and fuzzy—similar to a bumblebee’s, but without covering the entire back. Their abdomen, on the other hand, is shiny and black.
Eastern carpenter bees (Xylocopa virginica)—the most commonly found carpenter bee around Winnipeg—are about 19 to 25 mm long. Males have yellow patches on their faces, while females have solid black faces.
Carpenter bees are not an aggressive species—males do not have stingers, and females will only sting when provoked.
The clearest sign of an infestation is carpenter bees hovering around trees or wooden structures near your home. These bees may appear aggressive—males are especially likely to fly at humans—they will rarely sting (remember: The male bees don’t have stingers). Their main targets are other insects.
You may also see a hole or holes leading into the nest; there may also be signs of broken or mashed wood on the ground near the nest hole.
Carpenter bees spend our harsh winters burrowed deeply in their tunnels. In the springtime, carpenter bees mate. Space is made within their nests for eggs, which the bees stock with food. Carpenter bees don’t eat wood—their food source consists of pollen and nectar. Eastern carpenter bees lay about 6 to 8 eggs each season—each of those eggs will have its own chamber, which will be sealed off from the rest of the nest with wood pulp.
The eggs of carpenter bees hatch quickly; the species generally spend 2 days as an egg, 15 days as larvae, 4 days as prepupa, and 15 days as a pupa. Generally, adults emerge around August, feed, and then return to the same tunnel. The species lives 3 to 5 years on average. Each carpenter bee will build nests for itself, then a burrow for its young—the cycle continues from there.
Carpenter bees are not social insects—female carpenter bees provide food for their young and create burrows and nests without needing direction from a queen. Despite this, carpenter bees will often use the same nest and expand tunnels over generations—and that can lead to serious damage to wooden structures.
While carpenter bees can be startling, their non-aggressive nature makes it unlikely that they’ll sting you unless you actively disturb their nest. They don’t pose a significant danger to humans—the main problem with carpenter bees is the structural damage they can cause.
A single carpenter bee won’t do much damage at all; their burrows and nests are rather small. Problems arise after generations of carpenter bees have nested in the same wooden structure; this can damage the integrity of the structure, causing it to collapse. Decks, doors, gazebos, and other wooden structures are all susceptible to damage from carpenter bees; it’s best to catch carpenter bee infestations early.
Carpenter bees are important pollinators. To preserve carpenter bees, and other species capable of pollination, it’s always best to prevent infestations instead of having to eliminate bees.
Fortunately, preventing carpenter bee infestations is simple. Paint or varnish on wooden exteriors can discourage burrowing. A more creative strategy involves growing softwood trees or placing slabs of softwood away from your home. These strategies can encourage carpenter bees to burrow away from your home, preventing structural damage and giving you plenty of pollinators for any flowers you decide to grow.
When an infestation gets out of control, pest control may be necessary; carpenter bee activity can seriously damage structures over time. To eliminate carpenter bees, it’s best to call a professional exterminator—we use products that are specifically designed to eliminate bee nests without damaging surrounding plants. Where possible, we may also try to relocate the bees to a location away from the structures you’re trying to protect.
Carpenter bees don’t typically sting people—but when bees are found inside decks, telephone poles, doors, or other wooden structures, they may pose a risk over generations. Where possible, it’s best to attract carpenter bees away from your property or prevent them from accessing wooden structures by using paint or varnish to seal wood.
Though carpenter bees aren’t dangerous on their own, the risk they pose to property can be severe. Don’t worry if you see a carpenter bee—call the pros at Gilles Lambert Pest Control. We’ll assess the situation and protect your property.
