Next time you see a shiny black bumbler rumbling through the garden, don’t panic. Carpenter Bees generally do not sting.
Female Valley Carpenter Bees (Xylocopa varipuncta) are shiny black, while the males (in the video) are golden and fuzzy. Female carpenter bees only sting when provided and males do not have stingers. Another interesting bit of carpenter bee trivia: they are the only bees able to regulate their own temperature, which is why you may see them buzzing around when it's too hot or too cold for other bees.
These solitary bees got their name because of the way they tunnel into unfinished soft woods, such as pine, redwood, and fir. They also burrow into fences, sheds, and other wooden garden structures. These tunnels are used as nests for overwintering and creating new brood in the spring. Some of these tunnels can be as much as 10’ long!
This tunneling can weaken wood. Fill holes with steel wool and wood putty to protect trees, buildings and fences, once the bees have emerged. After treating the area, painting over the surface will help discourage the bees. You can use insecticides, in extreme cases, but it is better to create a habitat for them, because they are beneficial insects. Like honeybees, they are heavy pollinators. As they collect nectar and pollen from flowers, they pollinate your crops, increasing productivity.
One way to protect your fences and buildings, while enjoying the advantages of higher pollination rates, is to build a Carpenter Bee habitat. Simply take a chunk of soft wood and drill a bunch of 1/2” holes in one side. You can also use a bundle of 1/2” bamboo segments. Then mount it to a fence or post, to get it off the ground, and cross your fingers.
NOTE: The male carpenter bee in the video was released after filming. ;-)
I hope this information inspires you to grow more of your own food. You can ask your garden questions on my Home page.