Carpenter bees can be a serious pest, but also a valuable pollinator. While the adults are pollinators, the mated females bore into wooden structures. The results of this tunneling can be substantially damaging to the integrity of the structure, especially if the wood is weight bearing. A common misconception is the identification of carpenter bees vs. bumblebees. The body of a carpenter bee is metallic black with a glossy and hairless abdomen. Meanwhile, bumblebees look similar to carpenter bees, but the abdomen is hairy with yellow and black stripes. Bumble bees do not burrow into wood, instead they build their nests in the ground, typically in old rodent holes.
Biology and Lifecycle
The life stages of a carpenter bee are egg, larvae, pupa, and adult. A carpenter bee is not a social insect, unlike its counterparts the bumblebee and honeybee. A carpenter bee is considered a solitary insect, meaning only one adult in each nest and the eggs/larvae develop inside the nest. In March and April, females lay eggs in the tunnels. During egg laying, females forage pollen and pack it away for the larvae to be. Meanwhile, male carpenter bees guard the nest to prevent other females from entering and utilizing the tunnel to lay eggs. Once the egg-laying is complete, the females die off. By August, new adults emerge from the tunnels. These new adults forage on nectar and pollen, increasing their nutrient quantity for overwintering. These adults overwinter in pre-bored holes as temperatures begin to fall into the fall. Then in February, the lifecycle continues.
Damage
Female carpenter bees bore into wood. Leaving round tunnels less than half an inch in diameter in size. This has the potential to sacrifice the integrity of the wood. Woodpeckers are a predator to the carpenter bee. Woodpeckers will destroy the wood trying to access the larvae of the carpenter bee. This will rapidly deteriorate the integrity of the wood.
Carpenter bees may aggressively fly around during mating season, but they rarely attack humans. Male bees do not even have stingers.
Management
Carpenter bee traps can greatly reduce their population. There are many different traps available. These can include commercially produced plastic boxes with a block of wood on top or a homemade plastic bottle affixed to a 4×4 piece of wood with holes bored in it at an angle and many other designs are available as well. In these designs, the carpenter bees die within the container once caught. Plugging entry holes can also be effective, as the bees rarely make a second exit hole. This can be accomplished by hammering wooden dowels into the wood and coating them with a sealant such as glue or putty. The bees typically avoid oil-based painted wood for nest building. There are insecticidal options such as using a pyrethroid sprayed into the entry hole or depositing dust formulations inside the hole the bees will spread the insecticide throughout the hole. The downside is pyrethroid residual activity will not last more than four weeks. So, it will have to be re-applied often. Always wear proper PPE when applying insecticides.
Please reach out to your local UGA Extension Office with questions or concerns.
References:
Joseph, Shimat V. (2025, March 31). Carpenter bee: A pollinator but fond of wooden structures in the landscape. University of Georgia Entomology Research. https://site.caes.uga.edu/entomologyresearch/2025/03/carpenter-bee-a-pollinator-but-fond-of-wooden-structures-in-the-landscape/