Bumble bees have hairy abdomens, which are usually yellow and black. Carpenter bees abdomens' are shiny blue-black. Carpenter bees are solitary bees that do not form colonies and are nonaggressive unless provoked. Only the females possess a stinger. Males may buzz around a person's head but are harmless.
Carpenter bees get their name from the ability of the female to bore into wood.
The female then builds six to eight cells off the main tunnel and lays an egg in each. Larvae become adults by late August and September, but do not emerge until the following spring. Individual holes may not cause much damage but cumulative effects of numbers of bees can weaken structures. Wood surfaces can be painted to make them less attractive to bees. Stains seem to have little effect.