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Lyn Hacker: Those yellow-striped ninjas, aka carpenter bees, bringing out the worst in me

I don’t quite know how to say this, but I must confess, I am a murderer — not just an occasional murderer, but a pathological serial killer.  

I am a predator on the hunt these past few weeks, ever since the weather has changed. Armed with a fly swatter and a can of WD 40, I have slain carpenter bees who made the mistake of invading my rafters, eaves and deck, all with detrimental and damaging results. They are feeling my wrath.

Normally, I am a live-and-let-live-kind-of-woman. I love looking at coyotes and wouldn’t mess with them unless they start casting eyes at my horse, dog or cat. I don’t let either the cat or the dog run around outside unattended. The horse, well, he’d probably do the coyote more damage than vice versa, but still his stable and paddocks are close to the house.

Carpenter bee (Photo courtesy of Ric Bessin, UK Department of Entomology)

I keep the area around the house, garden and sheds trimmed back like I should, so as to dissuade coyotes, rabbits, squirrels, snakes and other critters from getting comfortable there. There are hawks up here who aid me in keeping that area cleared. I have about 12 acres of flat land, hills and forest, and the wild things are pretty much welcome to it. I feed the birds. I keep honey bees. I plant wildflowers for my bees, and let most of my pasture grow for the benefit of the deer, whom I don’t hunt. I even provide homes for the gentle mason bees.  

But when I can’t go out on my deck and enjoy a morning cup of joe without getting dive-bombed by those fat, buzzing, yellow-striped ninjas, I get fired up. “There’s 12 acres here,” I told a neighbor the other day. “They can have any tree they want, but not my house!”

Jeff Smith, Fleming County extension agent, wrote of carpenter bees, “These beneficial pollinators can cause considerable structural damage over time. Carpenter bees spend the winter as adults in their gallery homes. Now, they are starting new tunnels or expanding old ones in order to raise a brood of about six larvae during the summer.”

He continued, “A carpenter bee uses its strong mandibles to chew a 1/2-inch diameter entry hole into wood, then turns to follow the grain. The tunnel is lengthened at the rate of about 1 inch per week. Ultimately, it can be 6 to 10 inches long and can contain 6 or 7 individual larval cells. Each is provisioned with a ball of nectar and pollen as food for the grub-like larva. Over the years, galleries may become several feet long.”

Bumble bee (Photo courtesy of Ric Bessin, UK Department of Entomology)

The carpenter bee, or wood bee, is sometimes confused with the bumble bee as they are quite similar except for a couple of differences. First and foremost, they are voracious borers. The carpenter bee is a solitary bee, unlike the bumble bees, who like the honey bees are social and live in colonies.

They both have the characteristic yellow and black markings, but the bumble bee is more yellow. The carpenter bee has a shiny, black abdomen, while the bumble bee’s abdomen is fuzzy. Carpenter bees are wood nesters whereas bumble bees nest in the ground.

The female carpenter bee is less interested in people or animals as she is in taking care of her brood, but she has a painful stinger and will sting if agitated enough. The male carpenter bee does not have a stinger, but he is the more aggressive, actually dive bombing and hovering in your face if you’re anywhere near the nest. He’s the one that comes to meet you the moment you walk out of the door, then goes and gets his buddies so they can all dive bomb you and perform buzz-bys as you try to drink your morning coffee on your deck.

If you don’t know them by their preoccupation with your eaves, you’ll know them by what they leave behind, which is chewed sawdust lying on the railing or on the floor directly below their perfect holes. Their holes are exactly round, and just slightly larger than their body. They don’t eat the wood, but they do use it to build partitions for the 7 to 10 eggs they lay in the tunnels they bore. They can bore tunnels up to four feet long. They are not as destructive as termites, perhaps, but definitely can cause some structural soundness issues in decking support timbers.

I have been chided by my ecological friends — “Carpenter bees are great pollinators! “Why don’t you provide dummy nests for them? Just get some blocks of wood and drill holes for them.” I’m not sure I believe them. Truthful or not, it hasn’t worked for me. From where I stand, I’m reminded of the line that Jeff Goldblum’s character says in Jurassic Park, “T Rex doesn’t want to be fed. T Rex wants to hunt!”  

Carpenter bee damage (Photo by Lyn Hacker)

Carpenter bees, I’m positive, are not interested in moving into predrilled condos. Looking at a tunnel on a small roof support on my deck, I think carpenter bees want to drill wood, and lots of it.

Generally speaking, it’s not a very good idea to side your home in wood of just about any kind because of these bees, although pressure- treated, painted or hardwood is better. Too late for me. They love the soft woods like pine and cedar.

If you must side with wood, it’s recommended that it’s painted — not the natural look, like I love. Staining and sealing helps somewhat, but doesn’t fully prevent them. Pressure treated wood is supposed to be better, but my deck is pressure-treated and from where I sit, the bees could care less. They treat it like a university of higher drilling.

If you’re concerned, perhaps have seen a couple flying around, and don’t feel carpenter bee condos are the answer, there are several options. The first course of action is prevention — that is to actually use pressure- treated or better yet, composite wood and paint the surfaces that are in danger of being attacked. Unfortunately it does little good to stain and seal them, as I did. The actual painting is what deters the attraction. Smith also suggests covering attractive areas with metal or fine screening.

Second in the prevention arsenal is the liquid spray: carbaryl (Sevin), chlorpyrifos (Dursban) or a synthetic pyrethroid (permethrin or cyfluthrin) applied topically to whatever attractive wood is showing, according to Mike Potter, extension entomologist at the University of Kentucky College of Agriculture. Unfortunately, these preventive sprays are only good deterents for about one to two weeks and will have to be repeated as needed.

If you’ve got them and want to get rid of them, there are several options. Carpenter bee traps, found several places online, can be effective. Amazon offers an interesting array of solutions, everything from plastic bottle traps to an electronic tennis racket-looking gizmo that zaps them when you manage to swat them mid-air. I’ve gotten fairly good with my fly swatter, but its range is limited – the racket would be better. Or a badminton racket.

Besides the preventive sprays, existing holes and tunnels can be treated with carbaryl dust (Sevin) puffed into the openings, and Amazon also has an effective kit for this, complete with an angled gizmo to puff dust into the angled turn. Following dusting, the holes should be left open for a few days allowing the insects to distribute the insecticide. Then entrance holes should be plugged with wooden dowels or caulking to protect against future use and reduce the chance of wood decay.And, of course, you then need to paint the area.

“Flying insect sprays are also effective,” says Potter, except that they’re quite the flying acrobats and so actually hitting them with the spray becomes an issue. I like WD 40 because it shoots that great stream, and it’s cheaper than the expensive sprays. And at day’s end, you can be entertaining to watch, like I was, when Southern States showed up with my gas and found a somewhat wild-looking woman on her deck with a can of WD 40 in one hand and a fly swatter in the other, spraying, swatting, with streaks of WD 40 running down her walls and squashed carpenter bees scattered around her feet.

Lyn Hacker is a Lexington native raised by Appalachian parents to be not only educated but proficient in the living arts – working very hard, playing music, growing gardens, hog farming, orchard management and beekeeping. The UK graduate has been a newspaper staff writer and production manager, a photography lab manager, a Thoroughbred statistics manager, a Bluegrass singer and songwriter, a registered respiratory therapist, a farmer, a Standardbred horsewoman, a Red Barn Radio promoter and a beekeeper. Currently, Lyn is at work on a pediatric asthma primer as well as a novel called Loose Horse, while keeping bees with her family on her small, rocky Sadieville farm.

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