I have a problem with Carpenter Bees at my house and it's a battle I've been fighting for years!
Carpenter Bees, which look like big bumblebees, drill perfectly round holes into anything wooden - wood siding, wooden door frames, wooden lawn furniture. Once they drill into the wood, they make a sharp turn and tunnel another several inches and make their nest.
Generally, the female (which CAN sting) stays inside the nest, while the male (which CAN'T sting) spends a good amount of time outside the nest, buzzing around and divebombing anything and anyone that comes near.
Once you have Carpenter Bees, they can be hard to get rid of - the next generation, and the generation after that and so on, will continue to live in the same place. After a few years, a wooden fence can look like a Carpenter Bee condo. A bad infestation may require a professional exterminator.
If you have only a few, some people suggest putting "Sevin Dust" into the nest, and then plugging up the hole.
You can plug the Carpenter Bee hole with a wad of aluminum foil, and a piece of dowel cut to fit. Then, cover it with wood putty.
During the Spring, I keep an eye out for Carpenter Bees when I'm outside. If I notice one on the siding or door frame, I squish it.
If you spot a little pile of sawdust on the ground, look above it for a Carpenter Bee nest. If I notice a newly drilled Carpenter Bee hole, I sometimes stick a pebble into it - that stops the Carpenter Bees from coming and going, and makes the hole easy to spot so I can fix it later.
Creative Ways to Get Rid of Carpenter Bees
Carpenter Bees are difficult to get rid of, the males are annoying, and some people have come up with some very creative ideas about how to eliminate them. I've read about people who squirt the divebombing male Carpenter Bees with squirt guns; others have suggested smacking them with a tennis racquet while enjoying a cold beverage. One person I read about shoots them with a BB gun!
My preferred method is swatting the male Carpenter Bees with a badminton racquet and stomping them when they hit the ground. It works pretty well, but I imagine the neighbors wonder what I'm doing wandering around outside my house swinging a badminton racquet! If they ever ask, maybe I'll hand them a racquet.