Western Pest Services - Pest Library

Pest Library

Carpenter Bee
Xylocopa spp.

Class:

Insecta

Order:

Hymenoptera

Family:

Anthophoridae

Size & Characteristics:

Carpenter bee adults are about 1/2 to 1in (12.5-25 mm) long, robust. They are similar to bumble bees, except top of abdomen is quite bare and shiny.

Color:

California carpenter bee (mountains in Calif./Ore.) is mostly metallic green/blue with grayish wings. Female valley carpenter bee (valleys, lower foothills of Calif., Ariz.) is shiny black with bright metallic purple/bronze shine, smoky colored wings; male is golden brown or buff. Mountain carpenter bee (foothills/mountains of Calif./Ariz./Nev./Ore.) is black; male's head has yellow, white, black hairs

Geographic Range:

Carpenter bees are found around the world, with 7 species in the United States.

Comparison with other species:

Carpenter bees are similar to bumble bees, except that their abdomens are usually bare and shiny on top. Bumble bees have hairy abdomens with some yellow marks. Some robber flies are similar to bumble bees, but have just one pair of wings. Some hawk moths are also similar to bumble bees, but they have mouth parts that are siphons.

Habitat:

Although they do not form colonies, carpenter bees bore holes in wood to make places to rear their young. They prefer weathered wood. Valley carpenter bee uses partly decayed oak, eucalyptus and other hardwoods. California carpenter bee favors incense cedars and redwood trees. Mountain carpenter bee has been known to nest in structures.

Food:

Pollen, nectar

Biology:

After mating, the female carpenter bee bores a hole straight into wood, then turns and follows the grain of the wood, in order to make a gallery in which to lay eggs. She may use an old gallery from a previous year, or extend an old gallery. Beginning at the closed end, she lays an egg onto a mass of pollen and partly digested nectar, then seals it with chewed wood-pulp. She continues to do this once a day for 5-6 days. Mating is in the spring after individuals have overwintered in old tunnels. The survivors feed on nectar. Development from egg to adult takes 1-3 months.

Invasion:

They do not usually bore into painted wood. However, if they invade structural timbers, they should be controlled.

Damage:

Carpenter bees do not pose much threat to structures. Females have the ability to sting, but do not often use it. Males are quite aggressive with humans, sometimes hovering or buzzing around one's head, but they have no stinger.