Carpenter bees are large bees that are often mistaken for bumble bees and are known for their destructive and annoying habit of burrowing into dead wood. For homeowners around the world this means that any piece of exposed wood on the outside of home could become riddled with small almost bullet-like holes that serve as the burrow from which eggs are hatched. Wooden decks, wood shingles, dead trees and wooden house eaves and fascia are all prime targets for carpenter bee holes. The holes that the carpenter bees drill will rarely cause any sort of structural damage, but they’re unsightly and could open your wood up to rotting in the future.
I know all this because about three years ago I noticed some large bees flying around the side of my home and climbing up between the fascia boards and shingles of the side of my home. I also noticed little tell-tale streak of black dust coming down from behind my fascia, which told me something was burrowing up there.
I was tempted to try to use some sort of wasp or bee killing spray, but there were a lot of them and I wasn’t convinced that I could get the spray that high. So I called in an exterminator who taught me a heck of a lot about carpenter bees in a pretty short time.
The first thing everyone wants to know is: Do carpenter bees sting? It turns out that, no, most carpenter bees that we see burrowing into the side of homes (like mine) are male and the male carpenter bees do not actually sting. The female carpenter bees do sting, but they really need to be provoked, so the chance of a sting from a carpenter bee is fairly low when compared to other bees, wasps and hornets.
Most carpenter bees generally follow a pattern: in the spring they mate and find dead wood to burrow holes in. They lay an egg in the hole, leave in some food and close the hole back up. The egg hatches and the bee eats the food and emerges from the hole in late summer. They go back into the holes in the winter and emerge in the spring to mate all over again. Once you get a few carpenter bees they’ll often appear for a while and then disappear, but you might notice more holes being drilled in your wood deck or fascia board or wherever you have the problem.
It also turns out that my idea of spraying bee killer would have bee useless because it wouldn’t have gotten to the eggs and it probably wouldn’t have done much to the solve the problem. Professional exterminators actually find the holes and squirt in a sort of drying dust which doesn’t actually kill the carpenter bees until the emerge later in the summer. By killing the bees when they emerge they’re not able to mate and your carpenter bee problem is solved… at least for one season. Carpenter bees can always come back, which you may want to consider taking a more active approach to control your carpenter bee problem.
This old board shows the bullet-sized holes left by carpenter bees.
There are some tricks you can use to permanently prevent carpenter bees and some other wood pests and here are two methods I had a chance to employ recently when I was replacing a length of fascia board on my home.
When I tore down the old fascia board I immediately saw the little bullet holes which had told me carpenter bees had been at work at some point. I also noticed that the back of my fascia had never been painted, which was one of the reasons it was probably so tempting to my carpenter bee guests.
So the first way to prevent and control carpenter bees from burrowing into the wood around your home is to give your wood a good coat of paint and keep it in good condition. Now, paint is not a 100% guarantee against carpenter bees, but it’s one more layer that they have to burrow through. If you live in a log home or have wood you really can’t or don’t want to paint, there are also chemicals available which you can treat your wood with. The chemicals don’t last forever, though, and you may have to reapply them every couple of years.
Another option is one which I used: copper mesh. Carpenter bees and other wood borrowing pests can’t easily chew or dig or scratch their way through metal, and copper mesh is the perfect deterrent. After my first infestation of carpenter bees I got a roll of copper mesh and simply tucked it up into the little gap that was between shingles and fascia, which basically prevented anything (bees, birds, even bats) from climbing up there and doing any harm.
Here’s my copper mesh being stapled to the back of a fascia board.
I had a hard time finding this copper mesh in my local hardware stores (most had no idea what I was talking about) but you can actually buy copper mesh online
When I was replacing my fascia board this summer I decided to go one step further: since the carpenter bees had obviously found a gap and found a way to burrow into the back of my fascia before, I wanted to stop them in two ways.
First, I painted both side of my fascia board with two thick coats of paint.
Second, I Then I took some of the copper mesh I had and used a staple gun to basically cover the back of the fascia with an impenetrable barrier of metal. I made sure that my copper mesh covered the back of my fascia all the way down to the edge, in hope that it would prevent any clever carpenter bees from even trying to climb up into any sort of tiny gap that might develop between the fascia and my house over time.
Only time will tell if this really works, but for the relatively low cost of the copper mesh and the simplicity of the project, I figure it was worth the potential time and money I might later spend on an exterminator and new fascia boards.