by Neil Clark
Southampton County Extension Agent

“Hey, I’ve got a load of bumblebees around my shed and they are dive bombing me. How do I get rid of ‘em?” This is a familiar refrain this time of year.

“Ah, don’t worry about them, they won’t bother you.”

This is the phrase I commonly hear and sometimes commonly say when I get calls about carpenter bees (Xylocopa virginica). However, this is partly true based on some generalizations.

The first being that the males, which are typically the ones that dive-bomb, won’t sting you. And though the females can sting, (don’t read too deeply into this…..I’m not going there) they are typically non-aggressive and will only sting when trapped.

The second point is that they are different from bumblebees that are social bees, which nest in the ground. Carpenter bees don’t nest, but rather deposit their eggs in galleries that they bore into wood. Thus, the name carpenter bee, and the reason for all of the ½-inch holes you are finding in the rafters of your old barn.

Location is one easy “cultural” identifying trait as bumblebees are usually ground level, going between nest in ground and clover. This is why you got stung when you were 6 years old running barefoot on the lawn….. causing your vowed revenge on all things bumble-like, although you are now in your 50s and never go barefoot.

Bumblebees may pick up a little altitude if they are on a flowering tree or bush, but if they are around buildings and aggressively flying at you, these are carpenter bees. The higher-flying carpenter bees have a shiny black top to their abdomen (colloquially know as the tail), whereas the bumblebee has a hairy abdomen, often with yellow markings.

In general carpenter bees are not harmful, and in fact are beneficial pollinators, though they are more known for cutting through the sides of flowers to “rob” the nectar, without performing the pollen-bearing task for which most bees receive their reward.

Though the damage done from carpenter bees is not from the human nuisance of stinging. It is the boring and mess-making that are often the undesirable impacts.

Typically the pattern and amount of boring is not significant, but if the population and duration of subsequent boring becomes so great, structural damage to buildings can occur. The best way to prevent this is to apply a thick coat of paint to the wood surface.

This discourages carpenter bees from boring as they prefer softer uncoated wood. Unfortunately if the wood is untreated due to aesthetic reasons, stain does not create the same effect as the hard paint barrier. And, as the bees don’t actually eat the wood, the bees are unaffected by the wood treatment.

The best defense once you see that these critters have targeted your abode is to apply the powdered form of carbaryl, permethrin, esfenvalerate, or other materials labeled for carpenter bees. Always follow label directions.

And if all of this high-end treatment is too much, just swat ‘em with a tennis or badminton racket, though not exactly a “science-based” solution I suppose it could be entertaining and therapeutic for some, and folk indicate it works for modest-sized infestations.

NEIL CLARK is the southeast regional forestry extension agent and the unit coordinator at the Southampton Extension office.