CARPENTER BEE

DESCRIPTION: Carpenter bees are 1/2 to 4/5 of an inch long, blackish in color. The male does not have stinger. The female does have a stinger but rarely stings.

BIOLOGY: These bees burrow into the wood of structures to build galleries so therefore are considered wood destroying. Larval period extends from one month to one and one-half months and the pupal stage requires approximately two weeks. Males and females, over-winter, if the weather is not too severe. Adults may emerge in the spring, mate and then the female deposits her eggs.

Carpenter bees usually attack soft and easy to work woods, such as California redwood, cypress, cedar, and douglas fir. Bare wood, such as unfinished siding or roof trim, is preferred. The only external evidence of attack is the entry holes made by the female. These are round and 1/2 inch in diameter. A rather coarse sawdust-like frass may accumulate on surfaces below the entry hole. The frass is usually the color of fresh sawed wood. The presence of carpenter bees in wood sometimes attracts woodpeckers, which increase the damage to the surface of the wood. The carpenter bee tunnels turn at a right angle after extending approximately an inch across the grain of the wood, except when entry is through the end of a board. When they enter through the cut end of the wood they follow the grain of the wood in a straight line, sometimes for several feet. The tunnels are smooth walled. It takes several years of neglect for serious structural failure to occur.