killing beetles in wood

[Randall J Cox]

I have a piece of wood that I turned while it was green to make a candle holder about a year ago (about 10" high and 5" dia). Just today I got it down off the shelf in my shop and I think it has powder post beetles or something like that. I thought I read somewhere you can kill insects if you put the piece of wood in an oven (don't tell the wifey!) and heat to something like 130 degrees for x amount of time. I just looked in R Bruce Hoadley's book on Understanding Wood and nothing there on it (thought that's where I read it). Anybody know what temp will work and for how long. Randy

[Jacob Reverb]

Don't know the temperature you need, but I believe the only way you can protect it from PBB in the future is to either put finish on it and/or bring it into the house...

[Osvaldo Cristo]

I do not know the species you have in colder climates... for similar situation in a tropical country, our best option for small parts is to put the piece for a couple of weeks into the home freezer. Works great.

Never had listen about the use of the oven. It could work but can be a little but dangerous IMO. Woods have some volatile oils and if it is finished, even more... most of them flammable...

[Scott T Smith]

USDA kiln operators specs call for heating the wood until all parts reach 133F. You do no need to hold it there once you achieve it.

[Jeff Heath]

USDA kiln operators specs call for heating the wood until all parts reach 133F. You do no need to hold it there once you achieve it.

Yes, and the time it takes to get the internal temperatures depends on the thickness of the wood. I've seen reports of 4 hours, and also of 6 hours. I also recently read a paper, posted elsewhere, that ash lumber that is to be transported out of it's sawn area, in order to be certified bug free, had to be held at that temperature for a much, much longer time. I think it was 17 hours, but I'm going on memory, so not entirely sure it's an accurate number.

None of the lumber I cut would ever fit into the wife's oven, and there'd be hell to pay if I did it anyway.

[Richard Coers]

Most kiln operators will set the kiln to 150 degrees F to get the core of each board to 133-135.

[Ron Citerone]

I had a piece that made a beautiful top for a jewelry box that I suspected had some insect life in it since another piece from the same pile had some. I baked it in the oven at 130 for 2 hours and 3 years later all is well.

I wonder how hot a car in full day summer sun gets. I thought of that later, but never did it.

[Randall J Cox]

a closed car in full mid day sun in summer gets hotter than that...

[Randall J Cox]

Actually I went ahead and gave it 3 coats of poly, but that wont kill any bugs because there are many deep cracks in the wood (I turned it green) so it is not really sealed.

[John K Jordan]

Expert Gene Wengert said 130 degrees for six hours will kill any insect. But that temperature needs to reach the center of the wood which may require a heated environment of 160 deg or so to do it in a reasonable time for thicker wood. You can search the wood web for discussions and more specific guidelines or google for documents.

PPBs can stay in the wood for a couple of years before they come out. A sure sign of an active infestation is fine frass below the holes.

JKJ

[Jacques Gagnon]

USDA kiln operators specs call for heating the wood until all parts reach 133F. You do no need to hold it there once you achieve it.

The standard for heat treatment calls for the temperature at the core of the piece of wood to reach 56c / 133f for 30 minutes. Environmental conditions, type of kiln, volume treated, wood species and dimensions of pieces will influence how long it takes to reach the temperature at the core of the wood pieces.

[Matthew Hills]

Is anyone aware of sites that help identify insect infestations?'

I have a 4' walnut log that had ends painted with latex paint and then sat in stack for a year or two before I picked it up.
There were some bugs under the bark (including some type of wasp).
I noted a few holes in the ends -- are these something like PBB, termite, wasp, or some other organism? (or too hard to tell?)
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[John K Jordan]

Is anyone aware of sites that help identify insect infestations?'

I have a 4' walnut log that had ends painted with latex paint and then sat in stack for a year or two before I picked it up.
There were some bugs under the bark (including some type of wasp).
I noted a few holes in the ends -- are these something like PBB, termite, wasp, or some other organism? (or too hard to tell?)


Holes from powder post beetles make very small holes and they have powder-fine "frass" below them. The adult insect lays eggs on the wood surface and the hole is made a year or so later when the new insect emerges. There are lots of other insects that make holes in wood, such as carpenter bees which make large holes, nesting but not infesting. There is a lot of info on the web about ID and treatment. A quick search gave me this at the top (https://learningstore.uwex.edu/Assets/pdfs/A3093.pdf) but there are lots of better sites with good photographs of the holes and the insects

BTW, that log looks pretty far gone - the cracks may extend deep. Unfortunately, latex paint is not a good sealer. Several coats of oil-based paint is better. Even better is a coat of AnchorSeal or other green wood sealer, basically paraffin in a water emulsion.

JKJ

[Bill Dufour]

I suspect a finish coat seals out air so the bugs suffocate. I wonder if putting the wood in a bucket full of CO2 or any inert gas would suffocate the bugs. You would have to wait a long time. No idea how hibernating eggs might last. Perhaps a pressure cooker.
Bill D.

[Scott T Smith]

Yes, and the time it takes to get the internal temperatures depends on the thickness of the wood. I've seen reports of 4 hours, and also of 6 hours. I also recently read a paper, posted elsewhere, that ash lumber that is to be transported out of it's sawn area, in order to be certified bug free, had to be held at that temperature for a much, much longer time. I think it was 17 hours, but I'm going on memory, so not entirely sure it's an accurate number.

None of the lumber I cut would ever fit into the wife's oven, and there'd be hell to pay if I did it anyway.

Great response Jeff. Additionally, the MC% of the wood also plays a role. Higher MC% will take longer to reach 133 versus wood that is more dry.

One of my USDA manuals shows the time required based upon MC%, wet bulb and dry bulb temps. It's interesting.

[John K Jordan]

I suspect a finish coat seals out air so the bugs suffocate. I wonder if putting the wood in a bucket full of CO2 or any inert gas would suffocate the bugs. You would have to wait a long time. No idea how hibernating eggs might last. Perhaps a pressure cooker.
Bill D.

According to my reading many things have been tried over the years. Heat is still seems to be the preferred method, possibly since it is easy and inexpensive and works.

[Jim Andrew]

I used to put pieces of lumber with ppb in an old metal grain bin. It gets hot enough in there to kill ppb in summer.

[Bill Dufour]

I used to put pieces of lumber with ppb in an old metal grain bin. It gets hot enough in there to kill ppb in summer.

Where do you live?. I am sure the trunk of a car, in the sun, gets hot enough on a summer day when it gets to 110 in the shade likie it often did last summer here.
Bill

[Jim Andrew]

I am in Kansas, wheat country. Lots of metal grain bins in Kansas. Would think on a hot day in California, steel box, in sunshine probably temps near 180 degrees.

[Bill Dufour]

I have had soda cans explode in the trunk several times. Before I learned not to leave them there.
Bill D

[Randall J Cox]

What a great idea, trunk of car. Actually I have a black cover on the back of my pickup truck that sits outside. That damn cover gets so hot in summer you can't touch it without burning your hands - literally. I'm sure inside that bed is way up there temp wise. I'm just going to put my piece of wood in there when it gets hotter around here. I live in San Joaquin Valley in Calif and its way up over a 100F many days in summer.. (I never felt comfortable putting this stuff in oven - even though I have used both oven and freezer to expand/shrink shafts, etc for bearing changes.)

[James Biddle]

I used Borate I bought from Amazon and it worked fine...I think I'd succumb to the heat faster than the bugs

[John K Jordan]

I used Borate I bought from Amazon and it worked fine...I think I'd succumb to the heat faster than the bugs

Products like borate and tim-bor that are applied to the wood surface will keep new bugs out but won't get rid of bugs already in the wood.

[Allan Speers]

Products like borate and tim-bor that are applied to the wood surface will keep new bugs out but won't get rid of bugs already in the wood.


BoraCare will kill bugs already in the lumber, I guarantee it. (Tim Bor will not.)

You can make your own & save a lot of $$$, (Google it) but it's a messy, smelly business. Possibly grounds for divorce if you do it in the kitchen.


Another way, if in the summer, is to just wrap it in cheap black-plastic sheeting from Home Despot, then leave it in the sun.

[eugene thomas]

If have a slab of lumber would putting in a vacuum bag and letting sit at around 24 or so vacuum for few days do the job of killing bugs?

[Richard Coers]

Nope, you also have to kill the eggs too.

[Richard Coers]

BoraCare will kill bugs already in the lumber, I guarantee it. (Tim Bor will not.)

You can make your own & save a lot of $$$, (Google it) but it's a messy, smelly business. Possibly grounds for divorce if you do it in the kitchen.


Another way, if in the summer, is to just wrap it in cheap black-plastic sheeting from Home Despot, then leave it in the sun.

Will BoraCare also kill the eggs?

[Clint Baxter]

I went out and bought a large microwave. It'd be big enough to hold a piece that size no problem. Be an easier way to get that piece hot enough to kill any insect infestation. Also works well for speeding up the process of drying green wood.

Clint

[John K Jordan]

BoraCare will kill bugs already in the lumber, I guarantee it. (Tim Bor will not.)
.

Yay - we've got it in writing! Does your guarantee just cover the cost of the product or replacement of the furniture, or say, a log home? :D

Bora-Care will kill bugs in the wood as deep as it can penetrate. Nisus says it can penetrate up to 4" in about a month. It wasn't clear to me if that 4" was from one surface and one application will treat a 8" thick slab or if they meant it would treat a 4" thick slab if treated on both sides. It is recommended to saturate all surfaces, side, edge, and end grain.

In some cases they recommends multiple applications. According to the literature since it only kills bugs that are actively eating, eggs may survive. If bugs are deeper inside the wood than the Bora-Care has penetrated they may eat their way towards the surface and be poisoned there. For PPB this may take several years. If you cut the wood open before then you may expose an untreated surface for the bugs to exit.

The depth of penetration will certainly depend on the type of wood, density, and pores. I've never found recommendations on treatment differences, penetration depth, and effectiveness for various species. I also haven't found where recommendations for woods at various states of dryness - will it penetrate to the same depth and work the same on green logs as it will on "seasoned" logs or kiln-dried lumber?

I think it was mentioned here the temperatures and times needed for the heat treatment method.

JKJ

[Allan Speers]

Will BoraCare also kill the eggs?


You bet. - I know this for certain, John. The "active ingredient" is boric acid, (plus borates) which kills the eggs because it dries them out. Even if it didn't (which it does, I've seen it) the beetles would die as soon as they hatched and started nibling, since the stuff doesn't leech out over time.

Nisus possibly doesn't guarantee this, due to some legal issues.

----------------

IIRC, yes it can penetrate to about 4", if made correctly. (in one direction.)

I can post the (very detailed) instructions on how to make it, if anyone wants. (I think I still have this as a text file, somewhere) You can make it for about 1/2 the cost of the retail stuff.

- but again, it's a messy business and somewhat hazardous if you do not take certain precautions.

[Allan Speers]

I went out and bought a large microwave. It'd be big enough to hold a piece that size no problem. Be an easier way to get that piece hot enough to kill any insect infestation. Also works well for speeding up the process of drying green wood.

Clint

I would not use a microwave on wood! That will super-heat the lignen & fibers, and very possibly make the wood less strong.

[brian cammarata]

Allan....as you seem to be one of the SME on bugs infestation / treatment. Long story short I have some green / rough lumber and have purchased a gallon of boracare, what dilution should I do to preventative treat my stock. 1:1, 2:1, 5:1 the directions do not make sense. I assuming sray all sides an ends and let I air dry n use when EMC is reached. thanks advance

[Allan Speers]

Hey, brian.

I'll have to try and dig up my notes.

But the good news for you is that the stuff penetrates much better in green wood, due to the moisture content.
I'll see if I can find my notes later tonight. (It's been quite a few years since I dealt with this stuff.)

Also, in case anyone is wondering, I've never seen any white residue on my work, after milling wood treated this way. Sometimes you do get a little frosting on the surface, but it comes right off when you machine the lumber.

[Barry McFadden]

I would not use a microwave on wood! That will super-heat the lignen & fibers, and very possibly make the wood less strong.

I use a microwave at 40% for about 4 minutes..... take the wood out to cool a bit..it doesn't get hot enough so that you can't pick it up...and put it in for another 4 minutes...a third time if necessary. I also use this method to dry a green bowl after turning it.. the bowl will warp a bit (I think it adds character) but I haven't had one crack...then I put it back on the lathe to sand and finish.

[Tom M King]

If you use the recipe to make Boracare yourself, I recommend doing it outside on a day with a light breeze. Stay upwind. It is much cheaper, if you need a lot of it, but if you only need a gallon, I'd just buy it rather than go to the trouble of cooking it. I think there is a sticky here somewhere with the formula. Borax is about half in dollar stores what it costs in grocery stores here.

https://sawmillcreek.org/showthread.php?233066-Home-made-bora-care-amp-timbor

Some people use antifreeze for the ethylene glycol, but you can find ethylene glycol in large cities, in five gallon buckets for a little less than a hundred dollars, and it's clear. I was always reluctant to use anti-freeze, just because of the added color. If I need five, or ten gallons, I'll make it, but otherwise, it's not worth my time.

I have also found that Ortho Home Defense does not stain wood, and can kill a small infestation of old house borers by treating both sides of the wood.

[Allan Speers]

If you use the recipe to make Boracare yourself, I recommend doing it outside on a day with a light breeze. Stay upwind.


INDEED!


BTW, that sticky was from me. I didn't know it was still there.

I actually learned some new things and modified the info since then, (I've made the stuff three times) but the moderators were never able to update it for some reason.
Again, I'll try to find my notes tonight, if I have time.

[Tom M King]

Thanks a lot for the info Allan. I needed to make a large batch to treat some 1865 sills, and floor joists, a short while back, and remembered that sticky here. Your formula was followed. I used an outdoor cooker burner, and a large pot that was stamped to only be used for Boracare in the future.