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Barry Vabeach
06-08-2009, 7:41 PM
In the last 2 years I have been buying rough lumber off Craig's list, and this and other forums. I was told that some was air dried (some walnut and some oak) and others I was told was kiln dried ( cherry and walnut ) but I am not so sure it was. Anyway, recently I found some of the oak with powder post beetles - the holes and the frass ( dust ) indicating live , and some of the cherry and the walnut have the holes, though I can't be sure if there is frass or not and have decided the best course is to treat everything. From the internet I found that heating 4/4 lumber to temp of 130 or more for 2 1/2 hours or more will kill off the ppb and so I built a very small kiln on wheels, and have run a few loads through with no problems. Now that works though, I am not sure how far apart I need to keep the treated ( heated ) from the untreated. I have a small pressure treated lumber and black pipe rack - can I put some of the treated boards back on the lumber rack so long as they are not touching and are above the boards that haven't been treated. I stored the first few loads in my garage, but I am running out of room and life would be easier if I could take it from the rack one level at a time, and them return it to the rack but I have no idea how the beetles get from one board to the other. ( I considered putting swine flu masks on all the unifected boards - but that was too expensive ) Any suggestions apprecitated.

Bill Keehn
06-08-2009, 9:37 PM
A couple of years ago I picked up a nice looking cherry log on the side of the road. I took it home and cut it up on the bandsaw. I didn't know about powderpost beetles at that time. I noticed the holes but I thought they were from some long gone insect.

Weeks later on, I discovered I was wrong and lost a few pieces to them. They had bored through one board and into another that was in contact with it. Had I not moved that board I wouldn't have noticed because they never broke through any exposed surfaces.

I'm by no means an expert on this, but I think the grubs won't really migrate from one piece to another unless there is direct contact. Now the mature beetles are another story and I'm sure they cross open spaces. Luckily it seems they prefer cherry, especially with the bark still on.

Keep a clean piece of it near your untreated pile and I think your treated pile of other hardwoods will probably be left untouched for a while. They seem to prefer dessert first. When you are done, treat it and, keep it around. Examine it closely from time to time to see if re-infestation has occured.

Richard M. Wolfe
06-08-2009, 10:06 PM
Barry, I have that powder post beetles can be found pretty much anywhere. But the closer the proximity the more likely an infection. I stored some mesquite, which I consider 'prime rib' for powder post on some red oak and for the first time got powder post in the red oak. And I know, to boot, that the oak had been kiln dried. My favorite rant: Kiln drying does not bulletproof wood against the critters. Kiln dried material is generally taken down to 6-8% moisture, which is too dry for powder post. But if the wood is allowed to sit in a non-conditioned environment, especially a humid climate, it can easily absorb enough atmospheric moisture to take it to around 12% moisture, which is 'wet' enough for powder post to live in. However, it seems to me, and I can't quote any authorities, that aging or heating wood alters the makeup of sapwood, which is where the powder post live. They may bore a short distance into the heartwood but are after the sugars and starches in the sapwood.

To more directly answer your question, I think you would be OK to store the lumber in the same area but don't dead stack (use spacers) to separate boards and just keep an eye on it. Since powder post seem to get everywhere it doesn't seem to me to be mandatory to separate the two. Also, unless you want the look of sapwood in some projects cut all sapwood off something when you build it and you'll get rid of all but the rarest occurrence.

Barry Vabeach
06-09-2009, 7:12 AM
Thanks for the suggestions - I'll restack the treated in the shed, just keepinng the two stacks apart.

Mike Gager
06-09-2009, 8:39 AM
is there a way to spray the surrounding area to keep the bugs from getting to the wood in the first place? might be worth a call to an exterminator

Cliff Rohrabacher
06-09-2009, 9:49 AM
Painful experience has taught me to Pre-Treat all my home-seasoned lumber with an aqueous solution of Boric Acid. I make my own by boiling boric acid powder in water till no more will go into solution. Then I spray it on using a one gallon poly pump sprayer. I get the boric acid from an Agway.

The bugs that are already inside will eventually bore out. The ones outside that find the wood will eventually try to bore in. In either event the bugs have to tackle that outer 1/8” or so of surface wood where the solution penetrated. Then they die.

Bill Keehn
06-09-2009, 10:29 AM
Do you know if Boric acid dust presents a health hazard to people?

Larry Edgerton
06-09-2009, 11:02 AM
Kiln drying done properly kills powder post beetles that are already present, and any other insect infestation. It does it because the temperature of the wood is taken up to a point where the insects can not live.

It does not make the wood impervious to infestations in the future if stored carelessly. It does guarantee that the wood you are bringing into your shop is free of pests. This is where some people get confused on this issue. If the wood is stored next to an infected stack, it too will become infested.

I spray my wood down with a borax solution, and generally do not allow undried wood in the shop. I keep a few thousand feet on hand at times and am not willing to take the risk with air dried. It doesn't save enough money in my mind to worry about. Powder post beetles are everywhere so I spray on occasion just as a precautionary measure. It doesnt hurt the wood. I use 21 Mule Team borax, as was recommended to me by an exterminator.

Larry Edgerton
06-09-2009, 11:04 AM
Do you know if Boric acid dust presents a health hazard to people?

It is an eye wash......

Kyle Iwamoto
06-09-2009, 12:04 PM
The borax prevents ppb bettles? That is interesting. I'll have to get some and do some preventative spraying.
Just gotta love this forum.

Richard M. Wolfe
06-09-2009, 4:34 PM
I forgot to mention the borax solution....it would be good to use it. You can google for a treatment and find several 'recipies'. Also there are several commercial borate treatments - I use one called Timbor. As I recall it was something like $70 for a five gallon bucket and it lasts a long time. A borate powder is mixed with water and applied with a hand sprayer. The treatment sits on and barely penetrates the surface layer. Powder post beetles lay eggs on the wood surface and when they hatch the larvae bore into the wood. As they ingest the borate it disrupts their digestive system and kills them. I wouldn't drink it but it's not toxic and I was repeatedly assured that it would not affect any wood stains or finishes if the surface was not thoroughly planed or sanded. Also, the treatment is used in moist areas like basements as it also inhibits fungal growth. If there are any powder post already in the wood it will not kill them as it will not penetrate deeply enough. My guess is that it may kill the insect as it bores through the surface to emerge, but the damage would already be done.

David G Baker
06-09-2009, 6:44 PM
Boric acid is one of the safer (to humans and pets) bug killers that are readily available to the public.

Scott T Smith
06-12-2009, 10:59 PM
Kiln drying done properly kills powder post beetles that are already present, and any other insect infestation. It does it because the temperature of the wood is taken up to a point where the insects can not live.

It does not make the wood impervious to infestations in the future if stored carelessly. It does guarantee that the wood you are bringing into your shop is free of pests. This is where some people get confused on this issue. If the wood is stored next to an infected stack, it too will become infested.



+1.

At the end of the kiln drying process, the wood is sterilized by taking the load up to 135 degrees or higher. It is important to remember that the CORE of the wood needs to reach 135, which usually requires more than 2.5 hours in the kiln at that temp.

Bill Keehn
06-13-2009, 3:23 PM
So are Borax (20 mule-team borax) and Boric acid crystals the same thing?

Pat Moy
06-01-2010, 12:46 AM
Richard,
One of the seller's web site says Timbor leaves a white powdery residue after it's applied. Is this residue just on the surface?

Mike Archambeau
06-01-2010, 6:45 AM
Do you know if Boric acid dust presents a health hazard to people?

Treated wood will create dangerous dust later on during machining. I would be very careful with the boric acid on wood you will be using for your projects.

Boric acid is used on cellulose insulation so that the bugs don't eat the wood fiber. When humans breath the dust from the insulation, they get very ill (hair falls out, rapid weight loss, extreme fatigue, etc......just like dying a slow death).

Josh Bowman
06-01-2010, 7:16 AM
Do you know if Boric acid dust presents a health hazard to people?
We use tons of Boric Acid where I work, just a dust mask if you're stirring it up. It's kind of heavy so it doesn't make much dust. So far I haven't seen any ill effects of it. If it's mixed with water, it won't be bad at all.
Here's the material safety data sheet (MSDS) for it. Basically it's an irritant. http://www.sciencelab.com/xMSDS-Boric_acid-9927105
I've seen guys at work covered in the stuff and it didn't seem to bother them. If you're dog has an eye infection, the vet will tell you to flush his eyes with it.
Great stuff, kill bugs, stops infections and absorbs neutrons in a nuclear reactor!

Pat Moy
06-01-2010, 9:47 AM
I have a stack of mostly 6/4 hard maple and quarter sawn red oak, which I milled around 8 years ago. It was air dried outdoors for around 3 years, and has been air drying in my garage since. When I was milling the wood, I noticed small holes on the sap wood next to the bark so knew there were bark beatles present but wasn't too concerned. I tried to use some of the wood for a project recently, and noticed small holes (filled with frass) in the heart wood. Now I speculate there are powder post beatles. After reading posts from this thread, I thought a possible solution to salvage the wood would be to mix Timbor with water and spray. I planned to leave the treated stack in my garage a little while longer before use, reasoning that emerging beatles will die when they ingest the treated wood from the surface layer.

I'm now a bit concerned after reading Mike's comments regarding boric acid being toxic to humans.

What's the best way to treat this problem with maximum wood salvage?

Scott T Smith
06-01-2010, 12:46 PM
I have a stack of mostly 6/4 hard maple and quarter sawn red oak, which I milled around 8 years ago. It was air dried outdoors for around 3 years, and has been air drying in my garage since. When I was milling the wood, I noticed small holes on the sap wood next to the bark so knew there were bark beatles present but wasn't too concerned. I tried to use some of the wood for a project recently, and noticed small holes (filled with frass) in the heart wood. Now I speculate there are powder post beatles. After reading posts from this thread, I thought a possible solution to salvage the wood would be to mix Timbor with water and spray. I planned to leave the treated stack in my garage a little while longer before use, reasoning that emerging beatles will die when they ingest the treated wood from the surface layer.

I'm now a bit concerned after reading Mike's comments regarding boric acid being toxic to humans.

What's the best way to treat this problem with maximum wood salvage?


IMO the "best way to treat" would be to build an amonia fuming tent and fume it, or put it through a kiln sterilization cycle. I feel that these are best because you are not rewetting dried wood (although that too is an option).

I have not had any problems working with the boric acids, but I take the same precautions working with it as I do when working with any chemical - face mask, gloves and take a shower immediately after working with it.

Pat Moy
06-01-2010, 1:06 PM
I'm a bit hesitant with amonia fuming, but kiln sterilization is definitely a good method. I don't have access to a kiln. I was thinking maybe I can rig a temporary enclosure just so I can heat up the wood to 140 degrees for a couple of hours. Is that the right temperature and duration?

According to this web site:http://doyourownpestcontrol.com/timbor.htm , and the MSDA for Timbor (accessible via hyperlink on the same page), the product's not all that harmful to humans (but the "Potential Chronic Health Effects" section from the MSDA from Josh's posting sounded a bit more ominous). I also called the Timbor manufacturer about this. The rep I spoke to says that sawdust from treated wood does not cause much additional harm when compared to untreated sawdust. One other interesting thing she mentioned was that beatles do no ingest wood when exiting. Apparently, the insects only ingest wood on the way in, so untreated wood nearby can theoretically be infested by the emerged beatles.

I may still use Timbor, but I think heating the wood is the best solution. Does anyone have an idea on how to rig a temporary enclosure?

Maybe something like this: http://i302.photobucket.com/albums/nn98/ptmoyfb/misc/011202092_02-kiln-for-pine_xl.jpg will work.

Opinions?

Scott T Smith
06-01-2010, 10:25 PM
I'm a bit hesitant with amonia fuming, but kiln sterilization is definitely a good method. I don't have access to a kiln. I was thinking maybe I can rig a temporary enclosure just so I can heat up the wood to 140 degrees for a couple of hours. Is that the right temperature and duration?


Opinions?


You need to get the "center" of the board to 133F or higher for at least 30 minutes to sterilize. 2 hours may not be enough time for the center of the board to get that warm. Better to plan on several hours.

Rick Flower
06-03-2010, 4:11 PM
A solar oven comes to mind -- basically a large (however large you need) black box (made of plywood even) internally with a glass top with all sides sealed to ensure any sunlight entering does not get lost through cracks.. I had one of these a few years ago and it wasn't that well sealed and I could get it to about 135 with no fuel source -- just the Sun. A well sealed unit in a nice sunlit area with direct sun ought to be able to get well into the 140's for several hours depending on sun angle,etc. Just Google for "Solar Oven" -- there are tons out there.

P.S. If anyone wants it, I've got an unopen/still sealed bottle of Borrada liquid (I believe Borrada LP) that was purchased in the summer of '07 when we did some remodelling. I used one of these jugs but also bought the powdered variety.. I sprayed all of the accessible 2x4's and other beams while the wallboard was removed,etc.. It creates a sparkly surface that dries and should keep termites and other bugs away.. I gather that you can literally soak wood in it if you want to. Anyway, let me know if it's wanted and I'll make you a good deal! (PM me)

Pat Moy
06-04-2010, 10:02 AM
Thanks Rick. That's interesting info; I've never heard of solar ovens before. I googled the term as you suggested, and all sorts of materials came up, including some plans for simple home-made versions. Sounds like these can get potentially get a lot hotter than 135 degrees. What's a cheap and easy way to regulate temperature?

Homer Faucett
08-03-2010, 12:58 PM
You can get a pound of boric acid from Lowe's, HD, Tractor Supply, or probably even Wal-Mart for about $3. It's in the pest section, and usually in a squeeze bottle labeled as a roach or ant killer. Just check the active ingredients list. I've dissolved this and sprayed all my wood as it comes in with one of those pump up sprayers.

A cheap solar oven is 6 mil black plastic. You can make a wood burrito with the black plastic, and it will get nice and toasty in there . . . fairly easy to seal, and it would be better to elevate the burrito to prevent the ground from acting as a heat sink. If you guys find out a good way to regulate the heat inexpensively, I'd love to know, but I don't think it matters, as temps above 140 should be fine as well. Good luck!

David Helm
08-03-2010, 4:43 PM
The way the boric acid works is it makes adult beetles sterile. It doesn't kill any larvae already in the wood. Lyctids (commonly known as PPB) hatch at the surface, the larva finds an entry (usually at end grain) then bore away inside the wood till maturity when they exit via the small holes they bore. All the holes you see are exit holes. They then mate and continue the process. Boric acid works because it lasts a long time on the wood. Keeping the wood dry, with good airflow around it protects the wood also.

Scott Driemel
08-04-2010, 12:39 AM
Powder post critters are always interesting. You mentioned you bought the wood off of CL on occasion and I thought I'd just let you know the "depths" that these things can go. I cut down a bunch of soft maple 3 years ago. About 26"-30" butt logs. Beautiful and straight. They were out in the weather but had great circulation and were up on bunks. I just sawmilled one yesterday with my Lucas Mill and found just a couple of tiny black holes, maybe 4 or 5 over the entire length of a 12 foot log. Pretty much over a 4 foot length towards one end. I cut into the log 5/4 at a time. Those lavae bored almost 8" into the tree! Unbelieveable. I discarded all the 5/4X8" x12' boards I was cutting to be used in the fireplace, but was shocked as to how deep and straight towards the center they bored. I salvaged some hardwood from the centermost of the log but was very saddened to see the blighters do so much damage and especially that they went so deep. Just one more observation of powder posts and that's up here in the NorthWest.

Greg R Bradley
08-04-2010, 2:48 PM
Boric Acid hurts insects but is soothing to people in very small quantities. I believe this is why it is used in eyewash in a very low concentration.

I prefer to use it as insecticide around people and pets since it doesn't hurt either in reasonable quantities. I believe it kills bugs by dessicating them.

I follow the BBB method for my swimming pool. That means I added 120 pounds of boric acid to it a few years ago and add to it to maintain a 50ppm concentration of borates. I buy it at a scientific supply in 100 pound drums.

Jon van der Linden
08-04-2010, 9:53 PM
Heat is the best way to go. It doesn't take much if you're dealing with small pieces of lumber, you could even just wrap in black plastic and leave it inside your car on a hot day. I've seen some numbers on heat and insect mortality, and a five degree increase in temperature can double the kill rate. Anything over 130 degrees should do it in a couple hours.

The problem with these little critters is that they may not come out of the wood for years, and any poison has to come in direct contact with them. Borax will do nothing for pieces that already have grubs tunneling in them, unless you can find a way to shoot it down the holes. My understanding is that the eggs are the most difficult to kill.

I did some work recently in a house where they had some infested furniture. The furniture was purchased and fumigated in the 70's. It looks like the oak floor was infested before the furniture was fumigated. After having spent a lot of money on this "extermination" they found out much later that sections of their floor needed to be replaced and the reinfested furniture got tossed. I was the one that discovered the infestation this year - nothing like being the bearer of bad news when you're there for unrelated work.

ken gibbs
08-05-2010, 7:33 AM
Use the stock with powder post beatle damage if it is structurally sound. Charge more for the furniture that you make because it looks like an antique piece with distrewssed lumber.

Danny Hamsley
08-05-2010, 8:23 AM
Yes.

You can buy agricultural borax that is used as a fertilizer addition much cheaper than the advertised formulations for insect control. The active ingredient is the same. So, check with your Ag supply store or Ag fertilizer distributor and you can get the same basic stuff for a third of the Timbor type and SoluBor type formulations. I mix 1 pound of borate powder in a gallon of water in 4 gallon batches to be used in a back-pack sprayer. You can spray a lot of BF this way in a reasonable amount of time.

Kevin Guarnotta
07-10-2015, 1:04 PM
REsurrecting this thread - I have some Red Oak from a large tree I cut down in my yard. It has been air drying for over two years now. I'm slowly starting to use it in some projects. I have two stacks about 5' tall x 4' wide by 9 ' long. I just noticed some small holes, and dust - I am guessing I've got powder post beetles in my wood. After reading this thread, I'm thinking I need to treat the wood with a boric acid wash. Is it too late, if they have already bored into the wood? Do I need to take the stickered stack apart to spray it all, or can I just put the pump sprayer in between the layers, and spray away?

Any tips appreciated.

Tom Davis
07-10-2015, 2:50 PM
Three months ago I had cut down a lot of Bradford pear for my wife's wood turning hobby and stacked it under the lean to shed. There are probably 75 pieces 20 inches in diameter and 30 inches long. Two weeks after placing it under the shed it showed signs of active powder post beetle infestation (little strings of sawdust coming out of the ends which it been sealed with anchorseal). I called my local pest-control guys and they had me "tent It" heavy plastic with bricks around all the edges. They came out and put some sort of chemical in pie plates to fumigate the wood. They had me keep it under plastic for three days and there's been no sign of critters since. I supplied the vinyl and all the labor and it cost me a whopping $30 for them to administer the chemicals. I previously tried the boric acid wash on cherry logs with very poor results.

Yonak Hawkins
07-10-2015, 3:30 PM
Thans for this valuable response, Tom. I'd love to know what chemical the pest control guys used and if the infestation has abated or only delayed.

Cody Colston
07-10-2015, 4:29 PM
I'm thinking I need to treat the wood with a boric acid wash. Is it too late, if they have already bored into the wood?

I could be wrong but it's my understanding that treatment with a borate is a preventative, not a cure as it may not penetrate far enough to kill all the existing larvae. (those little holes and frass piles you see are the PPB's exiting the lumber after they mature) Heating the wood to 132 degrees at the core for a minimum of four hours is recommended for reliably killing an existing infestation. After heat treatment, then treat with a borate to prevent re-infestation.

Cody Colston
07-10-2015, 4:37 PM
There are probably 75 pieces 20 inches in diameter and 30 inches long.

:eek::eek::eek: That's a lot of huge Bradford Pear...the equivalent of 23 x 8' long logs or 3000 bf Doyle scale.

Was that 20" diameter or circumference?

I, too, would like to know what they used to fumigate the logs.

Scott T Smith
07-10-2015, 5:38 PM
I could be wrong but it's my understanding that treatment with a borate is a preventative, not a cure as it may not penetrate far enough to kill all the existing larvae. (those little holes and frass piles you see are the PPB's exiting the lumber after they mature) Heating the wood to 132 degrees at the core for a minimum of four hours is recommended for reliably killing an existing infestation. After heat treatment, then treat with a borate to prevent re-infestation.

Cody, the borate is both a preventative and it will also kill the larvae when they hatch and bore out of the wood. Heating is indeed the best way.

The problem with borate treating dry lumber is that the liquid causes the wood cells to expand, and then they will contract after drying - potentially causing surface checking. In some instances (such as a log cabin), you don't have many other options but in the case of furniture wood it is a solution, but not necessarily the best solution.

Yonak, you can build a home sterilization chamber and heat treat the boards yourself for not a lot of cost or hassle. There was an article in FWW a few years back that detailed the process. If you send me a PM with your e-mail address I'll be happy to send you the method.

Cody Colston
07-10-2015, 6:22 PM
Scott,

I realize the topical treatment will kill the PPB's as they bore out of the wood but what about the eggs that they leave behind? Also, I believe that PPBs can incubate for years before hatching. How long do borate treatments last?

I treat my lumber with Timbor immediately after sawing, as I sticker and stack it. The lumber is already wet. Can additional wetting of the surface cause surface checking? I've not really noticed it if it can/does.

Kevin Guarnotta
07-10-2015, 6:29 PM
Great Idea, thanks!

Tom Davis
07-10-2015, 7:09 PM
The stuff the pest guys used was PH3 , Aluminum Phosphide fumigant tablets.

Cody - the bradford pear count is 45 20"-22" with the rest 15"+. The loading, unloading, and stacking all most finished me off.

Allan Speers
07-10-2015, 9:49 PM
Painful experience has taught me to Pre-Treat all my home-seasoned lumber with an aqueous solution of Boric Acid. I make my own by boiling boric acid powder in water till no more will go into solution. Then I spray it on using a one gallon poly pump sprayer. I get the boric acid from an Agway.

The bugs that are already inside will eventually bore out. The ones outside that find the wood will eventually try to bore in. In either event the bugs have to tackle that outer 1/8” or so of surface wood where the solution penetrated. Then they die.


Just boric acid in water is not the optimum solution. What you want, for PREVENTION ONLY, is what they sell as "Timbor." It's water, boric acid and borax. Again, on freshly-milled lumber, or inside lumber being put outside for the first time, Timbor will prevent infestation, but that's all. It also can leave a white residue, which can cause problems later with finishing.

However, if you have lumber that already may have been exposed, then you need to spray it all with "Bora Care." This cost a lot more than Timbor, but it penetrates all the way through the wood, and kills any eggs & larvae already in there Timbor does NOT do this. Let's be very clear:
TIMBOR DOES NOT KILL EXISTING INFESTATIONS.

Realize that once you see the little mounds of dust, the bugs have already left the lumber, and have likely done tons of damage inside. If you see no dust mounds, they could be in there right now, chomping away, and they could emerge 2 years later, after you've built and finished you furniture.


I recently posted a detailed thread on how to make both solutions at home, for less than half the price of the retail stuff.

Scott T Smith
07-10-2015, 10:35 PM
Scott,

I realize the topical treatment will kill the PPB's as they bore out of the wood but what about the eggs that they leave behind? Also, I believe that PPBs can incubate for years before hatching. How long do borate treatments last?

I treat my lumber with Timbor immediately after sawing, as I sticker and stack it. The lumber is already wet. Can additional wetting of the surface cause surface checking? I've not really noticed it if it can/does.

The borate won't kill the eggs, but when the larvae hatches (1 - 2 year typical gestation cycle) they will ingest the borate as they bore out of the lumber, killing them and ending the cycle. Unfortunately sometimes they stay inside the wood for several years before they bore to the surface, which is one of the reasons why heat is the best method for PPB treatment. Heat kills everything - eggs, larvae, and adult beetles.

Unless exposed to water, borate treatments will stay in the lumber basically forever (however there is a caveat to this which I will explain in the next paragraph). They can leach out if they are in a stack of lumber that is stored outdoors (or in outdoor furniture), or on posts, RR ties, fence rails, etc that are exposed to rain.

Applying Timbor immediately after sawing is the best application method because the moisture already existing in the lumber helps to wick the borate solution deeper into the wood. It's best if you keep the surface saturated for 10 minutes or so to encourage maximum absorption. Depth of penetration is important since it's the residual effect that you're after. When you spray dry, rough sawn lumber the treatment probably won't go much deeper than 1/16". Unfortunately (and this is the caveat), typically at least 1/8" is planed off of each side of a rough sawn board, effectively removing all of the residual borate treatment and reducing the effectiveness of treatment. Lumber treated green has a deeper penetration rate.

Additional wetting of the lumber can definitely cause surface checking. This is easily observed if you stack and sticker a pile of lumber outdoors w/o cover. Over time you will notice that the upper layer becomes highly surface checked, but the layers underneath are much less so. This is because of rain rewetting the upper layer boards after they have started to dry.

There is an entire chapter in the FPL Air Drying of Lumber manual that addresses decay, including surface checks due to rewetting. The amount of checking is directly proportional to the amount of water absorbed by the lumber.

Allan Speers
07-10-2015, 11:30 PM
The borate won't kill the eggs, but when the larvae hatches (1 - 2 year typical gestation cycle) they will ingest the borate as they bore out of the lumber, killing them and ending the cycle. .


End the cycle? Who cares? What you want to end is the life of the eggs & larvae currently inside your wood. They can stay in there for up to (IIRC) FIVE YEARS, during which time they do massive damage. Do you really want to wait until they emerge to kill them?


Bora Care goes fully into the lumber, due to its glycol content, thus killing everything within a day or so. It also is much less prone to leeching out, again due to the glycol's ability to actually penetrate the wood cells. Bora Care costs more, and it's harder to make at home, but it's kind of a no-brainer for already-exposed lumber.

Kevin Guarnotta
07-11-2015, 7:30 AM
Thanks for all the tips. It sounds like that fumigation method is the simplest, and probably cheapest method. I just wonder if it gets deep enough into the wood. It sounds like the Bora Care shjould fully penetrate into the wood. What happens when you plane that stuff? Does it put some toxins in the air?
Will I need to unstack my whole pile to apply the bora care to each individual board, or can I just reach in between the stickers with a pump sprayer?

This is such a bummer - with all the research I did into turning the tree in my yard into lumber, having a portable mill come to my house, and stickering it properly - I never thought about an infestation. I have two rather large piles of wood. I have just started to use it more and more. I actually just finished a dining room table. Luckily I had pulled the wood for the table a while ago - and it had been sitting in my shop.

As for the heat treating - that sounds good, but I don't know if there are any kilns around here, and I don't think I have the resources to move all that wood either. Heat treating myself sounds like it could be a good solution. I'll have to look into that option. I also keep honeybees - and their hives are not far from the piles of wood - maybe 50' away? I would worry about any chemical treatment nearby killing my bees.

Scott T Smith
07-11-2015, 12:54 PM
End the cycle? Who cares? What you want to end is the life of the eggs & larvae currently inside your wood. They can stay in there for up to (IIRC) FIVE YEARS, during which time they do massive damage. Do you really want to wait until they emerge to kill them?



Allan,

I concur with you that a Bora Care type solution is the best method for treating already dry log cabin logs or timbers, etc that are not practical to place in a kiln, and I really enjoyed your posts about the homemade "boracare" solution and downloaded it for my records. It was extremely informative and well written. Thank you very much for putting that together and sharing it with us.

I think that you are misinterpreting my "explanation" to Cody as a "recommendation" though. Cody and I are both mill operators and work primarily with green lumber (which does not require glycol to wick the Timbor solution into the wood). Cody's post (which I was specifically answering) even references working with green lumber.

If you will go back and reread my posts you will discern that my preferred method of sterilizing lumber is heat. This is the only process approved by every lumber related sanctioning body. Timbor, Boracare, or any other boric acid or fumigation based method is not approved by every org, and as you know there are tradeoffs. I am not a supporter of rewetting already dry lumber, especially fine furniture lumber, due to the potential for surface checking to develop. I am also not a fan of using chemical solutions as the first choice when heat sterilization is well proven and leaves no toxic (or other type of) byproducts. Yes, chemical solutions do have their place.

I personally only use a 15% Timbor solution to treat freshly milled (green) thick slabs and timberframe timbers as an insect retardant during the air drying process. All slabs and most timbers are subsequently heat sterilized in one of my kilns after they have completed the air drying process.

Respectfully,

Scott

Allan Speers
07-11-2015, 1:04 PM
Understood, Scott, and yes that all makes sense.

Allan Speers
07-11-2015, 1:09 PM
Thanks for all the tips. It sounds like that fumigation method is the simplest, and probably cheapest method. I just wonder if it gets deep enough into the wood. It sounds like the Bora Care shjould fully penetrate into the wood. What happens when you plane that stuff? Does it put some toxins in the air?
Will I need to unstack my whole pile to apply the bora care to each individual board, or can I just reach in between the stickers with a pump sprayer? .


I have never seen any "borate dust" per se in the air when milling, but if it is there (and it probably is) then it's mixed in with the fine sawdust, and you are going to avoid breathing THAT anyway. The main thing is, in my limited experience, I have not seen lumber treated with the glycol solution cause any problems with finishing.

Must you coat it all? I have no idea. It's certainly a good idea to spray from the top, not the sides, so that gravity helps, though I don't know for certain that this is necessary. Maybe you could just continuously spray from the top of the pile for a long time, figuring the solution will pass through each board & eventually get to the bottom ones? That would probably be very wasteful, though, and the stuff ' aint cheap.

I coated all of my boards on all surfaces, because I had a pretty large problem. (I lost several thousand BF !) What I did was skip plane all 4 surfaces, so I could look for holes and trails, then cut-away the obviously infected sections. THEN I sprayed it all down.

I needed to rebuild my stacks anyway, (Get tarps underneath, and design-in more air flow.) so for me this was a no-brainer.

Allan Speers
07-11-2015, 1:51 PM
Three months ago I had cut down a lot of Bradford pear for my wife's wood turning hobby.... Two weeks after placing it under the shed it showed signs of active powder post beetle infestation (little strings of sawdust coming out of the ends which it been sealed with anchorseal). .....

Tom, that doesn't sound right. Everything I've read says the strings / piles of sawdust only appear when the mature larvae leave the lumber. Again, what I've read is: The beetle lands on the lumber and deposits eggs in cracks & crevices. There is no boring, per se. The eggs hatch, and the larvae start eating their way into the wood. They can live in there for 1-5 years, (depending on the exact species) before maturing and then boring their way out. It is only THEN that you see the tell-tale signs, which is why PPB are so serious a problem.

If this is not correct, then someone please correct me, and with details. However, if this IS correct, then you probably already had an infestation, several years before you cut down the tree. Was the tree sick, or had a dead branch, or previously hit by lightning? ? Why was it cut in the first place?

Those pesticides you used would certainly have killed any larvae left in the wood. (though it's likely that they had all left already.) The problem is, 6 months later when the mature females come back to re-lay eggs, the pesticides will have broken down and by then be useless.

Also, it kinda' goes without saying, but your wife needs to be extra careful when turning wood treated with chemicals. I hope she's wearing a respirator designed for such pesticides, not just a dust mask. (Borate powder gets trapped by normal dust masks.)

Cody Colston
07-11-2015, 5:03 PM
Cody and I are both mill operators...

LOL, that's like saying a Boeing 747 Captain and an ultra-light operator are both pilots! :D

All, I have an entry-level, fully manual, band sawmill. I saw lumber for my own use, both woodworking and construction projects. I have a 300 bf capacity solar kiln for drying.

Scott saws primarily QS Oak, often in dimensions that my little 30 hp tractor wouldn't even lift. He runs a commercial operation, has equipment and capabilities that I can only dream about and has run a dry kiln for many years. If you can successfully dry Oak, you can dry anything. I certainly defer to him on any wood processing topics.

Allan Speers
07-11-2015, 5:48 PM
The way the boric acid works is it makes adult beetles sterile. It doesn't kill any larvae already in the wood.

This is 100% contrary to what I've read. It breaks down the larvae's exoskeletons, just as it does on ants, termites, and roaches. The little critters dehydrate to death within 24 hours. Eggs simply dry up & die almost instantly.

In some white Oak that I recently milled, which was treated earlier this year with Bora Care, I actually found a lot of dead larvae, deep in the sapwood.
---------------

Perhaps what David was mistakenly referring to was the fact that an egg-laying adult only comes in contact with your lumber via it's reproductive system, so that's all that gets damaged. - On the mother.

Try sprinkling boric acid on an ant nest some time. By the next day, everything is wiped out.

Jim Andrew
07-12-2015, 9:47 AM
Could someone answer if this treatment will kill ash borers? And should you put it on the log before sawing for a few days, as they are supposed to live in the bark, and if that will get rid of the borers? Or do you need to spray each board?

Allan Speers
07-12-2015, 2:33 PM
Could someone answer if this treatment will kill ash borers? And should you put it on the log before sawing for a few days, as they are supposed to live in the bark, and if that will get rid of the borers? Or do you need to spray each board?


AFAIK, Borates will kill any insect with an exoskeleton.

As for your other questions, the bugs have to physically come into contact with the borates, that's all I can tell you.

Cody Colston
07-12-2015, 5:02 PM
Could someone answer if this treatment will kill ash borers? And should you put it on the log before sawing for a few days, as they are supposed to live in the bark, and if that will get rid of the borers? Or do you need to spray each board?

EAB eggs are laid in the bark crevices but the larva live in the cambium layer, just underneath the bark. They disrupt the flow of nutrients and the tree dies from the top down.

If you remove all the bark when sawing the logs, there is no further worry about the EAB. However, dry Ash lumber is highly susceptible to PPB's so it still needs to be treated to prevent infestation or heated to kill any existing infestation.

Jim Andrew
07-12-2015, 10:02 PM
The last time I sawed ash lumber, it was a little time between getting the log cut down and sawing it. There were borers in the wood by the time I sawed it. Took the boards to the air compressor and blew out the holes, thinking I rid myself of the borers. Stacked and stickered the boards, went back in a few months, and the boards were ruined from the boards having so many big holes. So I trashed them. Have not sawn any ash since, but could use some. Was considering spraying the bark with tempo, can buy from the coop. Label says it kills ppb, all sorts of bugs, but would prefer not to have to use it if this borate will work.

Allan Speers
07-12-2015, 10:24 PM
According to this: http://www.researchgate.net/profile/Pascal_Kamdem/publication/255645582_Borate_and_imidacloprid_treatment_of_ash _logs_infested_with_the_emerald_ash_borer/links/0a85e535522276eae4000000.pdf

The borate solution they tested was not very effective against ash borers. However, it seems they dod NOT use a glycol-based solution (surprisingly) the the stuff probably didn't penetrate far enough into bark. I would be very surprised if a glycol mix did NOT kill them.

How impervious to liquids is bark? Maybe that's the key? Maybe you could drill a bunch of holes, just bark-deep, before spraying. Then the glycol-mix would surely spread out underneath.


Also, on some arborist site, it mentioned having success by mixing boric acid, water, and SUGAR. Evidently, the borers love sweet sap, and the sugar entices them to ingest the borate solution. So, maybe mix up some Bora Care & add in a little sugar as well.

Scott T Smith
07-13-2015, 7:06 AM
LOL, that's like saying a Boeing 747 Captain and an ultra-light operator are both pilots! :D

All, I have an entry-level, fully manual, band sawmill. I saw lumber for my own use, both woodworking and construction projects. I have a 300 bf capacity solar kiln for drying.

Scott saws primarily QS Oak, often in dimensions that my little 30 hp tractor wouldn't even lift. He runs a commercial operation, has equipment and capabilities that I can only dream about and has run a dry kiln for many years. If you can successfully dry Oak, you can dry anything. I certainly defer to him on any wood processing topics.

<grin> Thanks Cody, but I'm still learning too!

Jim Andrew
07-13-2015, 9:46 AM
Says that they immersed the logs in the borate solution. That won't work for me. And putting the logs in a building after immersion will not either. Another thought, if you cut down an ash tree, saw it the same day, will the borers still be in the cambrium layer, so maybe if you cut the tree quickly enough, cut all the bark off, the wood might be clear of the borers. A guy could still spray some borate on the boards as you stack them, or maybe just put the tip of your sprayer in the gap between boards and spray away after you have the boards stickered and stacked.

Mark W Pugh
07-13-2015, 10:22 AM
Any photos of "Solar ovens" for long pieces of lumber? I have some long lumber that now I'm paranoid about.

Thanks

Scott T Smith
07-14-2015, 10:30 PM
Any photos of "Solar ovens" for long pieces of lumber? I have some long lumber that now I'm paranoid about.

Thanks

Define "long lumber"....

Most solar kilns based upon the Virginia Tech design are good for up to 16' board lengths.

Mark W Pugh
07-15-2015, 2:02 AM
That size would work.


Define "long lumber"....

Most solar kilns based upon the Virginia Tech design are good for up to 16' board lengths.

Scott T Smith
07-16-2015, 10:58 AM
That size would work.

As I recall, VT has two different designs - a small and large size. Here is a photo of the large size. The interior dimensions are a little over 17' long.

317494

Kevin Guarnotta
07-29-2015, 10:06 AM
Well, I got a quote from a pest control specialist. He said $900 to fumigate. I think that is their minimum. I need to load it into a truck, drive truck to them. They will then seal & tarp truck, fumigate. Let the truck sit for a couple days, then I can pick it up. They will not fumigate at my house - they say it is too dangerous. I understand that. I am in a fairly densely populated neighborhood.

They say the chemical will penetrate the wood - and there will not be any recurrence in the wood. ie the bugs won't come back. I like the idea of heat treating, but I am worried that the bugs can come back.

Now I just need to rent a truck, and get some help loading it into a truck!

Scott T Smith
08-02-2015, 10:34 PM
I like the idea of heat treating, but I am worried that the bugs can come back.



Kevin, heat treating is the only method approved by every single lumber organization in the US. If it is done properly (heating the core of the lumber to 133F for 30 minutes or more), all live bugs, eggs, and larvae will be killed.

Heat treating does not leave any type of residual chemical, which is good and bad. The bad part is that yes, the lumber can be reinfected. The good part is that you don't have to worry about exposure to potentially harsh poisons.

Kevin Guarnotta
08-03-2015, 8:15 AM
Hi Scott,

yeah I get that heat treating will work, but I worry about it not working long term. I am not very prolific woodworker, and I don't have an interior space to store this wood. So it is outside, and I think likely to be reinfected if I heat treat. I've got one pile 9' long by about 4' tall, but about 4' wide. The other pile is similar, but only about 3' tall. I prefer treating once.

Scott T Smith
08-03-2015, 11:18 AM
Hi Scott,

yeah I get that heat treating will work, but I worry about it not working long term. I am not very prolific woodworker, and I don't have an interior space to store this wood. So it is outside, and I think likely to be reinfected if I heat treat. I've got one pile 9' long by about 4' tall, but about 4' wide. The other pile is similar, but only about 3' tall. I prefer treating once.

Kevin, your approach makes sense and your concerns are valid.

marty shultz
06-14-2017, 10:48 PM
Resurrecting the thread again.

I cut and milled a walnut tree in AZ 3.5 years ago. The 9/4" wood was air dried for 16 months when I discovered the dust from some type of beetle (powderpost?) I did some research, purchased bora-care and applied it as directed. I was under the impression that the beetles would leave within a year and never return again. I milled some of the wood two weeks ago. The sap wood has significant damage and the beetles continue to make dust.

I called the technical rep who makes the bora-care. The rep told me there isn't any fool proof way to make the wood beetle free. I believe he said the eggs could be in the wood for 5 years before they hatch and start the cycle up again.

Not sure what to do now. Someone suggested putting the wood in the attic. The outside temp in phoenix next week is 118 degrees in the shade. My attic will probably be 170 or so. I could put some wood up there for a several days.

Scott T Smith
06-15-2017, 9:37 PM
Resurrecting the thread again.

I cut and milled a walnut tree in AZ 3.5 years ago. The 9/4" wood was air dried for 16 months when I discovered the dust from some type of beetle (powderpost?) I did some research, purchased bora-care and applied it as directed. I was under the impression that the beetles would leave within a year and never return again. I milled some of the wood two weeks ago. The sap wood has significant damage and the beetles continue to make dust.

I called the technical rep who makes the bora-care. The rep told me there isn't any fool proof way to make the wood beetle free. I believe he said the eggs could be in the wood for 5 years before they hatch and start the cycle up again.

Not sure what to do now. Someone suggested putting the wood in the attic. The outside temp in phoenix next week is 118 degrees in the shade. My attic will probably be 170 or so. I could put some wood up there for a several days.

Marty, in order to sterilize the lumber and kill all eggs and larvae you need to heat the boards until they are 133F throughout. Stickering the lumber in your attic in Phoenix for several days should do the trick. It would not hurt to store it excess lumber up there as well.

marty shultz
06-17-2017, 11:05 AM
any other suggestions to the above post?

Scott T Smith
06-17-2017, 8:30 PM
any other suggestions to the above post?

It's posts such as this that discourage me from sharing my knowledge on an internet forum.

marty shultz
06-17-2017, 9:22 PM
It's posts such as this that discourage me from sharing my knowledge on an internet forum.

Hey Scott - I didn't see your response to my post. I'm not sure exactly why. Maybe it's due to the nested responses. At any rate, I didn't think anyone had responded so I thought I was giving my own post a 'bump'

I appreciate your knowledge and will take your advise. I hope I don't pass out in the attic!

Cheers,

Marty

Jim Andrew
06-17-2017, 9:34 PM
I sawed a bunch of walnut and red elm a couple years ago, and stacked it along the edge of an open pole shed, so it would be in the shade, and out of the rain, but would get plenty of air flow. The red elm got powder post beetles, and I found the powder flowing out of the holes, so moved the elm to a metal grain bin, which gets very hot during summer. Have used a bin to clean up boards with ppb, as the heat lasts a long time during hot summer days. The walnut still has not shown any signs of ppb, it was UNDER The red elm in the pile. Was concerned it would get infected, as there was some dust that fell down onto the walnut.
Had considered buying a shipping container to store lumber in, they are all steel with a wood floor, and should get pretty hot inside during the summer here in Kansas, does that seem like a good idea? Would like to put wood right off the mill into the container, with stickers of course, and I could possibly run an extension cord into the container to run a fan or 2, and maybe a dehumidifier. Any comments?

marty shultz
06-17-2017, 10:21 PM
I sawed a bunch of walnut and red elm a couple years ago, and stacked it along the edge of an open pole shed, so it would be in the shade, and out of the rain, but would get plenty of air flow. The red elm got powder post beetles, and I found the powder flowing out of the holes, so moved the elm to a metal grain bin, which gets very hot during summer. Have used a bin to clean up boards with ppb, as the heat lasts a long time during hot summer days. The walnut still has not shown any signs of ppb, it was UNDER The red elm in the pile. Was concerned it would get infected, as there was some dust that fell down onto the walnut.
Had considered buying a shipping container to store lumber in, they are all steel with a wood floor, and should get pretty hot inside during the summer here in Kansas, does that seem like a good idea? Would like to put wood right off the mill into the container, with stickers of course, and I could possibly run an extension cord into the container to run a fan or 2, and maybe a dehumidifier. Any comments?


The shipping containers I've been in in the summer are hot. Not sure if they reach the 140 range or not.

Scott T Smith
06-18-2017, 5:29 AM
Hey Scott - I didn't see your response to my post. I'm not sure exactly why. Maybe it's due to the nested responses. At any rate, I didn't think anyone had responded so I thought I was giving my own post a 'bump'

I appreciate your knowledge and will take your advise. I hope I don't pass out in the attic!

Cheers,

Marty

Marty, no harm - no foul.

Heat sterilization is a much better option than Bora-care, and heat sterilization is 100% effective. Good luck in that hot attic!

marty shultz
06-18-2017, 11:05 AM
Marty, no harm - no foul.

Heat sterilization is a much better option than Bora-care, and heat sterilization is 100% effective. Good luck in that hot attic!

I have a shed too. I'm going to check the temp in there today. Much easier access and cooler!

Jim Andrew
06-18-2017, 10:13 PM
If I had to to achieve 140 degrees, could paint the top black.

marty shultz
06-20-2017, 5:12 PM
Well, the temp in phoenix yesterday was 115f. I touched the side of my black truck bed and it was hot (140f at 8:00 am)! I decided to keep the wood in the back of my truck, separate it a bit so air could get to the surfaces reasonably well and cover the bed with clear plastic.

The temp outside is 120f today. An IR thermometer gun shows the outside of the plastic is 143f. When I stick the gun under the plastic the temp ranges from 178f to 200f.

The wood ranges in thickness from 1.75" to 2.0" and its core temp was approx 105f when I put it in the truck. The temp inside the bed should stay close to 180 for around 6 hours. Do you think that is long enough to kill the beetles?

thanks

362437

Scott T Smith
06-24-2017, 5:55 PM
Well, the temp in phoenix yesterday was 115f. I touched the side of my black truck bed and it was hot (140f at 8:00 am)! I decided to keep the wood in the back of my truck, separate it a bit so air could get to the surfaces reasonably well and cover the bed with clear plastic.

The temp outside is 120f today. An IR thermometer gun shows the outside of the plastic is 143f. When I stick the gun under the plastic the temp ranges from 178f to 200f.

The wood ranges in thickness from 1.75" to 2.0" and its core temp was approx 105f when I put it in the truck. The temp inside the bed should stay close to 180 for around 6 hours. Do you think that is long enough to kill the beetles?

thanks

362437

Yes, 6 hours at 180 should do it.

robert baccus
08-16-2017, 11:09 PM
Years ago I had a beautiful Magnavox steroe 8 years old start dribbling sawdust--guess what.

Scott T Smith
08-20-2017, 4:18 PM
Resurrecting the thread again.

I cut and milled a walnut tree in AZ 3.5 years ago. The 9/4" wood was air dried for 16 months when I discovered the dust from some type of beetle (powderpost?) I did some research, purchased bora-care and applied it as directed. I was under the impression that the beetles would leave within a year and never return again. I milled some of the wood two weeks ago. The sap wood has significant damage and the beetles continue to make dust.

I called the technical rep who makes the bora-care. The rep told me there isn't any fool proof way to make the wood beetle free. I believe he said the eggs could be in the wood for 5 years before they hatch and start the cycle up again.

Not sure what to do now. Someone suggested putting the wood in the attic. The outside temp in phoenix next week is 118 degrees in the shade. My attic will probably be 170 or so. I could put some wood up there for a several days.

The technical rep is wrong; the "foolproof" method to sterilize lumber is with heat. Properly done It will kill live insects, larvae and the eggs.

you need to heat the lumber until every bit of it reaches 133f. A hot attic in Arizona should do the trick. Stack and sticker it and put some fans on it to force the hot air across the faces of the boards. Place a temperature sensor with a tell tale indicator by the discharge side of the lowest board.