There are over 500 species of carpenter bees and they live worldwide. They are large, black, sturdy bees with a shiny abdomen, and they love unpainted wood because if the the wood is painted they do not recognize the object as wood. Their favorite wood is cypress, cedar and redwood. But they will take any wood that isn’t painted if they have no choice. They like the wood to be about 2 inches thick. The males do not have stingers only the females do and they will sting but only if strongly provoked. And, if you see carpenter bee around your house, you should definitely set up a bee trap.
Carpenter bees make their tunnels near the surface, so there isn’t a chance of structural damage unless the bees are not treated, then they will continue to make tunnels off the entrance/exit hole, and then structural damage can happen.
The bees make a nearly perfect circle hole entrance and then tunnel at 90 degree angles creating tunnels to lay their eggs. Common places the carpenter bee can be found include eaves, shingles, window frames, wood patio furniture, undersides of beams and tree limbs. The bees do not eat the wood they tunnel through.
Some tell tale signs that you may have carpenter bees are as follows: saw dust piles underneath circular holes, stains directly underneath the holes which comes from the bees defecating and groups of bees swarming one area.
Carpenter bees will hibernate in the tunnels during winter, mate in the spring, and their babies are born in the summer. Because of this cycle the best time of year to first treat for carpenter bees is in the spring and again mid-summer and then one final time in early fall.
It is best to treat carpenter bees at night, when they sleep to avoid aggravating the female bees and lessen the risk of getting attacked and stung. Be sure to wear protective gear that covers every exposed skin area. Use a flashlight with red cellophane taped across the light as carpenter bees cannot see the color red.
The best way to treat carpenter bees is to apply an insecticide that is blown through a puffer and creates a dust that will go directly into the holes. The bees will continue to go in and out and will carry the dust on their legs and wings deeper into the existing tunnels. In order for this to happen you should not close up the holes immediately after spraying. When you are ready to close up the holes in the fall, you can use putty, caulking material, cork or steel wool.
Some sprays that are environmentally safe are boric acid, almond oil as bees hate the smell of almonds, and Citri Fresh Bee Stop. You can even make your own citrus spray by boiling oranges, lemons and limes. After boiling put the liquid in a puffer gun and spray into the holes.
If you continue to have carpenter bee problems you may need to call in a professional.