Common Name: Carpenter bee
Scientific Name: Apidae: Xylocopa virginica
Status: beneficial as pollinators but can be a pest of wooden structures
Damaging Stage: adult

Biology: A carpenter bees closely resembles a bumble bee except that the upper surface of its abdomen is bare and shiny black, and lacks the hair that is so distinctive in bumble bees.

Carpenter bees overwinter as adults in wood nests. They emerge in the spring and mate. Females excavate tunnels in wood and lay their eggs within a series of small cells. Pollen is brought to the nest for the larvae to feed on until they emerge as adults in late summer. There is one generation per year.

Injury: Carpenter bees nest in a wide range of woods used by people including wooden fences, utility poles, firewood, trees, and lawn furniture. They usually cause aesthetic damage to exposed bare wood surfaces in buildings and decks. Like carpenter ants, carpenter bees do not feed on wood. Damage to wooden structures occurs when the adults drill holes into and excavate tunnels for shelter and nesting.

Carpenter bees are often considered nuisance pests because they swarm near buildings and may seem dangerous to homeowners.

Action Threshold: Carpenter bees are valuable pollinators and normally do not cause serious structural damage to wood unless large numbers are present over several years. If damage occurs in an area that is highly visible, controls may need to be applied.

Management: Chemical controls are somewhat effective if applied repeatedly every few weeks. The best method to reduce populations is to treat the entrance of burrow holes to ensure the insecticide is introduced to the pests and then filling in the holes with wood putty or another compound after the bees are gone.