Powder post Beetles

[Tom Raymond]

I have some reclaimed beech flooring in my house. It has been machined, sanded, oiled and waxed. I used the left overs to make sheves in my closets and the top of a window seat. It has been installed for nearly three years. My wife is now finding larva coming out of some of the worm holes.

How do I get rid of them?

What are the chances of them moving into the rest of the house?

Since autocorrect capitalized Beatles should I name them? Maybe I'll start with Prudence.

Thanks

[Marc]

You'll have to check the label but I don't think oil or wax interferes with the application of Boracare. AFAIK, the stuff is transparent once applied. That or get the flooring out of the house...quickly.

Marc

[Jim Baird]

...not to worry, Tom. That is if you have the lower case beetles as I do.

I installed yellow pine #1 flooring in the master suite addition to my house in 1996. About 12 years later I saw little sawdust piles at random locations and little 1-3 mm holes. I even saw some little green worms that I reasoned could not come from anywhere else.

Called exterminator with whom I have had annual contract for decades. He drove out the next day, looked, and said "forgetboutit". When you see those little worms emerge the game is over. I think the worm turns into a beetle again or something, but the damage he has done in emerging is minimal and almost never structural. The guy said if it drives you crazy you could try fumigating the whol house, but you might not reach whatever organisms still lurk.

He told me the incubation for these is 2-10 years, but here we were looking at 12 yrs. Last spring I saw a few more emerge, at 17 yrs. I never have tried to fill the cavities because they are so small and few. I do have pics of the worm if you want to compare.

The flooring I bought was #1 and great looking, almost clear pine, but I think now that its grade was common, not select, air-dried instead of kiln, and was likely meant for outdoor porch use.

I would ratchet down the anxiety level over this several clicks.

[John Kogel]

Could become a problem in the future.

[Tom Raymond]

I haven't seen any beatles. Just larva. They look like lawn grubs but about the size of a grain of rice, maybe not even that big. The 70+ year old barn beams had worm holes before they were milled into flooring. I thought the holes meant the bugs had already left.

My anxiety over them is pretty low, the price per gallon of bora care was more startling. My wife was ready to gut the addition.

[Jim Katen]

Beetles don't emerge at the larval stage, but stay in the wood where they're safe and protected. They also don't emerge from existing holes, but pupate just below the surface and emerge from a new hole as adults, ready to go on dates.

If you've got little worms in or near the holes in the wood, they're probably something else. Have you had a lot of moths in the house lately?

[Marc]

I haven't seen any beatles. Just larva. They look like lawn grubs but about the size of a grain of rice, maybe not even that big. The 70+ year old barn beams had worm holes before they were milled into flooring. I thought the holes meant the bugs had already left.

It does mean they left, but only to infest elsewhere.

My anxiety over them is pretty low, the price per gallon of bora care was more startling. My wife was ready to gut the addition.

From the comments thus far posted, I gather that not all PPBs are the same. The ones here represent an epidemic. They do more damage than all other wood destroying insects combined, including subs. I've written off quite a few old raised-pier homes because PPBs had ruined the entire structural floor system - beams, joists and subfloor. In those cases, I usually document it with a photo of my screwdriver penetrating the entire thickness of a joist. In the worst cases, I can crumble the joist with my bare hands.

Marc

[mjr6550]

I believe that to reinfest the wood has to have a very high moisture content. Maybe heat from a heat gun or hair dryer would be enough to kill them in the wood that is in place?

[Jim Katen]

I believe that to reinfest the wood has to have a very high moisture content. Maybe heat from a heat gun or hair dryer would be enough to kill them in the wood that is in place?

Depends on the beetles. Some will reinfest the same wood that they emerged from, others only reinfest living trees, still others require sunlight. Low moisture content might not prevent reinfestation, but it can really slow down the beetles when they're in the larval stage. Some have the ability to enter diapause and effectively suspend their metabolism for years.

Heat from a heat gun or hair dryer would probably damage the wood before it killed the beetles deep inside. Some years ago, people were experimenting with small handheld microwave emitters for this purpose. The emitters were in the form of plates - like irons - that would be held against the wood. I never heard what happened with that technology, but I suspect that it wouldn't sell very well. People freak out about stuff like that.

[rdhutch]

It does not sound like Powder Post Beetles to me. I agree with Jim Katen's analysis. The most obvious clue was the presence of larvae. Wood destroying beetles do not exit in the larval stage.

[mjr6550]

I believe that to reinfest the wood has to have a very high moisture content. Maybe heat from a heat gun or hair dryer would be enough to kill them in the wood that is in place?

Depends on the beetles. Some will reinfest the same wood that they emerged from, others only reinfest living trees, still others require sunlight. Low moisture content might not prevent reinfestation, but it can really slow down the beetles when they're in the larval stage. Some have the ability to enter diapause and effectively suspend their metabolism for years.

Heat from a heat gun or hair dryer would probably damage the wood before it killed the beetles deep inside. Some years ago, people were experimenting with small handheld microwave emitters for this purpose. The emitters were in the form of plates - like irons - that would be held against the wood. I never heard what happened with that technology, but I suspect that it wouldn't sell very well. People freak out about stuff like that.

I see a lot of signs of powder post beetles in old farm houses (usually timber joists, often with the bark at the sides). The basement are usually quite damp, but even then active infestations are rare. OTOH, maybe after 150 years all the beetles have left the building.

Regarding the heat gun, I guess I was thinking of killing the emerging beetles. If they are not emerging I suspect that using heat would not be practical.

[Tom Raymond]

The larva look like PPB larva pics online. I havent seen any beetles, and really not much of an emergence. One little worm.

[Jonh]

I think the best treatment of ppb is microwave shashel. just fry it

[Tom Raymond]

We had a pretty large emergence over the last week. The floor has been removed. The only live adults that remain are in a jar so I can identify them (shaking the jar isn't as satisfying as you would think). They look to be anobiid.

There are no signs of damage on the plywood subfloor, or the pine and plywood frame of the closet system.

Before I put the new floor down should I treat? With what? I can't find any of the borate treatments (boracare, Timbor and the like) locally. The only boil acid I can find is roach powder.

[Bill Kibbel]

Boric acid is used here for treating and preserving old exposed hewn-log buildings. The powder is really cheap, like 3 bucks a pound.

I would think that if it's labelled for roaches, it's the same stuff. Probably 95-100%. I don't know if anyone still does it, but folks used to make up solutions with ethylene glycol (anti-freeze) as the carrier to treat old timbers.

[Jim Katen]

We had a pretty large emergence over the last week. The floor has been removed. The only live adults that remain are in a jar so I can identify them (shaking the jar isn't as satisfying as you would think). They look to be anobiid.

There are no signs of damage on the plywood subfloor, or the pine and plywood frame of the closet system.

Before I put the new floor down should I treat? With what? I can't find any of the borate treatments (boracare, Timbor and the like) locally. The only boil acid I can find is roach powder.

Post the best picture you can take of the beetles. If they're anobiids, then there's really not much risk. They need relatively high moisture levels to re-infest anything other than the wood that they started in. You might have been able to leave the wood in place and let the beetles run their course.

If they're lyctids, then they're capable of reinfesting very dry wood. It's worth pre-treating with a chemical before proceeding.

If you treat with anything, use Boracare. Amazon has it for about $70 per gallon and you can dilute it with 5 parts of water for preventive care. That's not particularly expensive.

Probably the easiest way to tell the difference between the two families of beetles is to look at them from the top. Lyctids have distinct body sections of head, thorax, and abdomen. Anobiids, look like they only have two body segments and the head is not particularly distinct.

[Tom Raymond]

Boric acid is used here for treating and preserving old exposed hewn-log buildings. The powder is really cheap, like 3 bucks a pound.

I would think that if it's labelled for roaches, it's the same stuff. Probably 95-100%. I don't know if anyone still does it, but folks used to make up solutions with ethylene glycol (anti-freeze) as the carrier to treat old timbers.

I found a recipe for that. 4 pounds of borax in 1 gallon antifreeze. Bring to low boil and reduce by half. Cool. Mix 1:1 with water.

Sounds pretty nasty for my bedroom.

[Tom Raymond]

We had a pretty large emergence over the last week. The floor has been removed. The only live adults that remain are in a jar so I can identify them (shaking the jar isn't as satisfying as you would think). They look to be anobiid.

There are no signs of damage on the plywood subfloor, or the pine and plywood frame of the closet system.

Before I put the new floor down should I treat? With what? I can't find any of the borate treatments (boracare, Timbor and the like) locally. The only boil acid I can find is roach powder.

Post the best picture you can take of the beetles. If they're anobiids, then there's really not much risk. They need relatively high moisture levels to re-infest anything other than the wood that they started in. You might have been able to leave the wood in place and let the beetles run their course.

If they're lyctids, then they're capable of reinfesting very dry wood. It's worth pre-treating with a chemical before proceeding.

If you treat with anything, use Boracare. Amazon has it for about $70 per gallon and you can dilute it with 5 parts of water for preventive care. That's not particularly expensive.

Probably the easiest way to tell the difference between the two families of beetles is to look at them from the top. Lyctids have distinct body sections of head, thorax, and abdomen. Anobiids, look like they only have two body segments and the head is not particularly distinct.

The two segment appearance is why I think anobiids. There was some variation; about 3/16 long with small mandible, and slightly smaller with lafge mandible. Gender? I'll see if I can get a good pic.

I opted for Bonide. It was available locally and I could treat this morning and prep this evening. My new floor arrives tomorrow and only needs 48 to 72 hours to acclimate. The contents of my room are spread out all over my little house. I want to get it back together asap.

[Jim Katen]

. . . I opted for Bonide. It was available locally and I could treat this morning and prep this evening. . . .

Never heard of it. What's in it? Is it listed for use indoors?

[Tom Raymond]

Permethrin, some petroleum distilates, and most likely a lot of water. It's concentrated. Use full strength outside or dilute 5 ounces with 1 gallon of water for indoors. Bonide makes a bunch of garden type insecticides, products for fruit and vegetables, greens, and flowers and shrubs. I had never heard of it either until calling around looking for an alternative to boracare. I saw a Bonide commercial on TV late last night, so it must be good.

I mixed mine a little hot, closer to 8 ounces. Painted on the subfloor with a roller on a pole. Zero odor while wet. A very slight soapy smell when the plywood was damp but dry enough to walk on. Zero odor when dry.

The best part of the project was teaching my daughter to use the pneumatic stapler. She's 5 and usually hates the compressor. She likes it a little better after stapling a sheet of underlayment.