There Is a Reason for Calling Them Carpenter Bees!
Those big, black bees are starting to appear around the homes now. These bees are called carpenter bees, and they can be a nuisance this time of year. Not only do the bees dart at anything that walks by, they also burrow into almost any wooden structure they can find.
Carpenter bees look like bumble bees, however they are bigger and do not have any hairs on their back end (a shiny hiney). Male carpenter bees are the ones you normally see hovering around the house and can be distinguished from the female by a white dot on his forehead. Male bees do not sting; however, they act aggressive when they are trying to guard the female’s nest.
The female burrows into wood to form a tunnel for her nest. Each tunnel contains just one female’s nest, which is provisioned with pollen balls for the hatching larva. The female carpenter bee will eventually seal the tunnel off to prevent predators from getting to her young.
No wood is entirely safe from a determined female bee. Carpenter bees will even bore into painted and pressure treated wood. One or 2 tunnels should not harm the structural integrity of the wood; however numerous holes may be a point of concern. Woodpeckers that are trying to find bee larvae could cause further damage.
Getting rid of carpenter bees is not easy. Spraying insecticides on wood surfaces to prevent boring has inconsistent results since the bees do not actually eat the wood as they burrow. The only effective control is to spray the pesticide into the hole entrances and then seal them up with caulk so they cannot be used next year.