The most common wood boring bees found around homes are carpenter bees (Xylocopa). Often mistaken for bumble bees due to their similar appearance, carpenter bees can be differentiated by their black abdomen, which lacks the yellow hairs found on bumble bees. Carpenter bees, while large, are not an aggressive insect. Only females can sting and will do so only when provoked. Carpenter bees are more of a nuisance around homes due to their tendency to construct nests in deck furniture, playground equipment, awnings and other untreated exposed wooden structures. The removal of carpenter bees can be a simple process.
Identify the location where unwanted carpenter bees are nesting. Nests are easy to find as these large bees will often hover around them. Males actively defend their nests and fly around intruders, but they are harmless and cannot sting. Nests are easily identified by a small, circular opening on bare, weathered wood.
Apply pesticides of choice to the identified nest to kill wood boring carpenter bees. Spray insecticides labelled for bee and wasps are highly effective on carpenter bees as well. If the nest is well developed, applying an insecticidal dust (diatomaceous earth or boric acid) into the opening will kill the bees by abrading their protective exoskeleton. Desiccant dusts are much less toxic to the environment than synthetic sprays.
Fill the remaining hole with steel wool and patch with caulk or cover with a weather resistant putty to prevent other unwanted bees from returning. Cover any other cracks in the wood that you notice in the same area with caulk or putty to prevent the likelihood of other wood boring bees from building a nest.
Apply the pesticide late in the evening when the wood boring bees are not active. Though carpenter bees aren't aggressive insects, you should wear protective clothing as a precautionary measure when dealing with them.
Pesticides are toxic. Always follow the instructions on the label of the pesticide you use. Do not allow children or pets around the nest until it has been successfully eliminated and patched.