The distinctive noise of carpenter bees is easily found this time of year, especially if you have any wooden structures near your home. These insects, large, black and yellow bees, are the culprit of half-inch holes in wood, small piles of sawdust on the window seal, and annoying homeowners so much they sometimes resort to whacking these insects with a tennis racket.

The carpenter bee got its name because of its ability to tunnel in wood with its jaws. The holes go a short distance into the wood and run horizontally with the grain for at least six inches or more. Several bees may use the same entrance hole and branch off in different directions from the main tunnel. The tunnels may go for several feet in the wood if the same entrance hole is used for several years.

Trusses, overhangs, wooden decks and other exposed wood on houses attract the bees. Wood that is treated or painted is less preferred but still susceptible to attacks.

Unlike termites, carpenter bees do not consume the wood as food. Instead, they gnaw tunnels to create nesting sites. Carpenter bees overwinter in tunnels and emerge in early spring. Female bees lay eggs in the tunnels until the tunnels are full. Male bees do not drill tunnels, but they are protective of their territory. The male is distinguished from the female by a white spot on the front of the face.

Female carpenter bees seldom sting but will if disturbed or handled. Male carpenter bees cannot sting, but they often become aggressive and frighten people by flying about their heads. Carpenter bee larvae are large and noisy. The noise they make may attract woodpeckers. The woodpeckers do further damage to wood when hunting for the larva. Woodpeckers seen on the eave of homes are more than likely in search of the carpenter bee larva. Adult bees die within a few weeks.

At least three methods can be used to control carpenter bees: 1) aerosol treatments of insecticides applied directly to adult carpenter bees, 2) residual surface and gallery treatments with insecticides and 3) preventive treatments such as painting wood with thick coats of oil-based or latex paints.

Several days following the preferred treatment, after carpenter bee activity has ceased, plug holes with plastic wood, caulk or with other suitable materials. If carpenter bees continue to attack the wood, additional residual insecticide treatments may be required at weekly or twice weekly intervals. Painting the wood with an oil-based or polyurethane paint will discourage the bees, but will not make the wood bee-proof.

Trapping the bees with homemade contraptions has also gained popularity, but the overall effectiveness of control has not been tested. These traps usually consist of a jar or bottle at the bottom of untreated wooden box. The idea is for the bee to drill into the wood or utilize pre-drilled holes. Once inside, by design, the bee is unable to leave the trap. The jar or bottle should be removable to empty on occasion.

For additional questions, contact Effingham County Extension Agent Sam Ingram at 754-8040 or singram@uga.edu.