Treating carpenter bees is done by treating each individual burrow. The goal in treating the burrow is to exterminate the adult and the egg inside. Not treating carpenter bees can lead to a great deal of damage to wood structures. If a carpenter is needed to replace wood damaged by the bees I can give you the name of a contractor if needed. Some wood with light infestations can be repaired with putty but structural pieces of wood should be replaced. A carpenter bee tunnel can be 8 to 12 inches long in length and having multiple burrows can leave a board almost hollow.
What Are Carpenter Bees?
People often mistake carpenter bees for bumblebees, which look quite similar. Bumblebees nest in the ground, usually in abandoned rodent nests, and live in social communities. Carpenter bees are solitary bees that burrow into wood. If you see a bee that looks like a bumblebee emerging from a hole in your porch, it's a carpenter bee, not a bumblebee. You can differentiate the two by examining the dorsal (upper) side of the abdomen. If it's shiny and hairless, it's a carpenter bee. A bumblebee, by contrast, has a hairy abdomen.
Carpenter bees usually spend the cold months tucked inside their empty nest tunnels, protected from freezing temperatures and winter weather. In spring, they emerge ready to mate. The female carpenter bee excavates a tunnel for her offspring. In each brood chamber, she stores food and lays an egg. By late summer, her young emerge as adults. The new generation of carpenter bees will visit flowers briefly in August and September, before settling in for the winter.