i dont know, but i do know that "great stuff" will kill them, but once it dries another one will just dig it back out. the only thing i have found to work is fresh paint
well your the second person to tell me that about fresh paint, so i guess that is the way im going, i hurd if you use a silicone based hole filler the bee's cant eat back out the hole???
I use to take a fly swatter or narrow thin strip of wood and drill a few small holes in end to let air pass when i swung at them and let them have it! Some days i really killed them.
The spatula works pretty well if you happen to be outside grilling? I had to bring another clean out to use for the grill after I smacked three of them.
Alot of suggestions in the thread below from just a couple of days ago.
They do not like to eat through paint. So paint wahtever they are chewing into.
But if you have time, an old tennis racket makes for a fun afternoon. I killed 8 Wednesday afternoon. I do fill the hole with silicone and they do smother.
I have cedar siding and carpenter bees are a problem.
I spray Ammo, cypermthrin, under the eves and over hangs every three months. Then I look for bee activity this time of year and spray the areas on the siding where they start burrows.
The ammo has stopped them from burrowing in the eves and overhangs. They still burrow in the siding, but will leave as soon as you spray the ammo.
The cypermethrin has extremely low toxicity to warm blooded animals.
I have a shed they're boring into, I sprayed some bugbgone on it yesterday evening and when I looked this morning, there's two dead on the side of the shed
Any wasp, hornet, bee spray will do the trick. If you see 'em flying around looking for a place to bore into, go ahead and hit 'em with the spray. If you have holes where they've already bored in, spray into the hole, wait a couple of days, then fill the hole with wood putty or caulk then paint. You'll have to keep after 'em year and year because they like to come back were they were born.
Don't ever let anybody tell you they never sting either! The females can and do sting sometimes. I picked up a wooden boat paddle in my jon boat one time and was immediately stung not once but twice. Darned bees had bored into the paddle and when I picked it up, my hand was right over the hole with the shebee in it. A year or so later, I also learned not to spray bumble bees with ant spray...it just makes em madder. Got stung that time 5 times before I could get off the ladder.
Here is what I have done for the last three years and it has worked well.
Initially sprayed Drione Dust into each hole (decent qty) or removed the affected facia board and replaced.
Cap each Hole with 1.2 inch tapered cork, they are caught inside with the poison and results in dead Carpenter Bee
Each spring I spray the eves and other areas down with Cypermethrin liquid spray.
Haven't had a problem since starting this. All products can be bought at one of the local "do it yourself" pesticide stores.
When I was a kid I used to wait on a bunch of them to fly into their hole and take a can of hairspray and a lighter and give them a little fire and brimstone!