I photographed this Wood-boring Bee chewing a hole in our mailbox post. There were 3 or 4 of them flying around checking for their nest holes. It is not hard to see how these bees can chew a nest tunnel into wood when you look at those large mandibles (mouthparts). These are solitary bees, so they are not as likely to sting while protecting their nests. This type of bee is different than the Carpenter Bee, which looks like a Bumblebee.