Carpenter Bees & Carpenter Ants…Chewing Away at Historic Structures
By Pat Kelley, ACE
As you sit on the wooden porch of the historic home built in the early 1900’s, the buzzing and chewing sounds of the carpenter bees working high up in the fascia board dominate the quiet morning. Each spring brings the return of these large solitary bees. Every year they bore perfectly round, dime-sized holes into exposed wood surfaces, leaving piles of freshly chewed wood below.
Carpenter bees and ants are a major threat to the integrity of historic structures across North America and abroad. Although neither pest actually eats wood, both can cause structural damage if they are left to carve out their nests in the wood siding and supports of a wooden structure. Here is a little bit of information about each.
Carpenter bees: The female carpenter bee will choose an area of exposed wood that is generally un-painted and in an area that is protected from the rain. The female will bore straight into the wood for a couple of inches and then will make a 90-degree turn to the right or left for 6-8 inches. She eventually will lay several eggs in the tunnels that she has created.The male bee hovers outside of the hole guarding it from predators. The males may dive-bomb a person when they get too close to the hole, but remember the males cannot sting. Most activity is in the late spring. Often times, woodpeckers will cause the majority of damage in the wood as they seek out the juicy bee larvae.
Carpenter ants: These large black ants will generally nest in dead trees, injured trees or old firewood outdoors. They create clean galleys within the wood, dropping sawdust and dead insect parts into a pile beneath the nest. Mature colonies can have up to 4,000 ants and will send off winged “swarmers” a few times a year to set up satellite colonies. A large colony outdoors can eventually lead to an infestation within a structure. Carpenter ants prefer
soft or moisture damaged wood to make their nests and will travel up to 100 yards in search of food.