Powder Post Beetles

[Tim Sherwood]

I have some poplar boards , from the recent group buy, that have powder post beetles. There are also a few red oak boards with beetles holes in the sapwood. I have isolated these boards, OUTSIDE my shop while I decide if this wood is worth the risk of trying to save it.

From the entomology reports I read, the holes just show where the last crop of adults have left the wood. The adults tend to exit in the Spring. They leave their eggs and larvae behind. The larvae stage lasts about a year. The eggs can continue to hatch for several years.

Treating the surface with Boracare or similar products, will kill the adults as they exit. It might penetrate far enough to kill some of the grubs. But it has little effect on the eggs. So These boards are still a risk for a couple of years. You won't know if they are all dead until several Spring-times have passed and there are no new holes or piles of dusty frass.

You can cook the boards in a kiln. But that is not an option for most of us.

Would you risk keeping this wood ?

 

[KenOfCary]

I'm also interested in the answer to that question. I'd also ask if there is anybody locally that has a kiln and would be willing to sterilize about 100 bf of 8' pieces of lumber for a (hopefully small) fee. Not sure if anything I got from the run has beetles but I'm also not sure it doesn't - would rather be safe than sorry.

I got rid of the soft maple that was heavily infested. What I have after getting home is almost all White Oak rather than Walnut but that works for me.

 

[Jeff]

You can cook the boards in a kiln. But that is not an option for most of us.

It's probably not worth the risk to fiddle around salvaging a little lumber that was only $1.25/bf.

Check out the larval lifetime here.

https://extension.entm.purdue.edu/publications/E-73.pdf

 

[thsb]

Scott Smith posted about a straightforward way to create a small sterilization chamber at home (i searched this site for powder post beetles and found it but not sure how to post that thread). i am thinking about doing that for the walnut i got but i guess it probably isn't necessary.

 

[Phil S]

I also have the need to cook some eggs. How hot and for how long ??

 

[Willemjm]

My experience is that once the lumber gets to below 12% MC, they will not survive. In black Walnut they only survive in the sap wood. They love wet English Walnut.

I would suggest looking for fresh shavings at the exit holes, if there are none they are probably long gone. Also, if they are active, they are actually audible, as you can hear the munching or chewing activity in the boards.

If you wish to fumigate, just spray with Borate and close in plastic wrapped around the lumber. A roll of plastic from lowes is inexpensive.

 

[KenOfCary]

Calling on Scott or some other expert sawyer to provide us some real information and advice. Please..

How virulent are these suckers and how apt are they to spread. Looking for personal experience and not web references.

 

[allisnut]

I have approximately twenty 8' 1x8s that my grandfather sawmilled in the 1930s and used building barns. I want to use this for cabinet doors and drawer fronts. I have planed and sized some pieces and stacked them in my shop. As I move them around I have seen a few small dust piles indicating active beetles. I would have thought after 80 years the boards would be dry enough that there would not be any activity.

For what its worth, I called Ellis Lumber in Shelby today. They will run my lumber through a sterilization cycle in their kiln. Their minimum fee is $75, but I don't know what volume of lumber that corresponds to. I may need to haul another batch from the farm to the shop to get my moneys worth out of their fee.

I, like Ken, am interested in real world advice from those in the know. I've heard of people throwing out their entire wood stash over powder post beetles, but that seems a little extreme.

 

[Willemjm]

Seems as if some of the comments refer to my post.
No ego here, but just want to indicate that my post referred to the heading of this thread being "Powder Post Beatles"
Insect infestation includes many other critters, some showing up furniture built and finished decades ago.

 

[Tim Sherwood]

Tim, you may not need to worry about any of the walnut. I didn't see any holes except in the poplar, and some red oak sapwood.

 

[Jeff]

We had a similar discussion in July that we all will benefit from. Scott Smith provided some "sawyer facts" about powder post beetles and cooking critters.

http://www.ncwoodworker.net/forums/showthread.php?t=59793

See Scott's post #4 in that thread...

The best post-infection treatment is heat sterilization. You need to heat the boards until all portions of the lumber reaches 133F or greater for at least 30 minutes. You can build a simple home heat treatment chamber from foil faced foam board, sawhorses and a space heater, or you can take the lumber to a commercial wood kiln for treatment. FWW had an article a few years about about the home heat treatment method.

Also some pics from a follow-up thread by the OP.

http://www.ncwoodworker.net/forums/showthread.php?t=59847

 

[CrealBilly]

I couldnt agree with mr Smith more... if you want to get the eggs then heating as he suggested is the way to go. But remember the inner center of the lumber has to reach or exceed the noted temperature and remain at that temperature for the given time or more to achieve sterilization. You cant just heat the outside of the wood and expect it to work.

 

[Xlogger]

I rent my kiln out for $50 day one and $20 a day after. You load on one of my pallets. I can turn the heat up to start and have it over 135 degrees in about 12--16 hours.

 

[Tim Sherwood]

Considering the small quantity of wood involved, about a dozen boards, I think this batch is headed to the dump.

 

[scsmith42]

Calling on Scott or some other expert sawyer to provide us some real information and advice. Please..

How virulent are these suckers and how apt are they to spread. Looking for personal experience and not web references.

As previously quoted, standard industry specs call for heating the lumber until the CORE of the boards reach at least 133f for 30 minutes. Somewhere I have a chart that shows how long it takes heat to penetrate based upon thickness, but unfortunately I don't have access to it right now.

Borate based treatments come In a very, very distant second choice to heat sterilization. For starters, borates have poor penetration in dry lumber and frequently do not kill eggs. They are better than nothing if you cannot heat sterilize, but do not expect 100% success from treatment.

Ppb WILL spread and infect your other lumber. Because they can exist for several years inside your lumber, you might not see visible signs until after your project is complete and in use.

We frequently heat sterilize small batches of lumber for others, so feel free to contact me.

Scott

 

[ste6168]

This thread has got me worried now. It sounds as though the walnut, at least the heartwood is fine, nothing to worry about. Same goes for the cedar. The lighter stuff, whether it was the oak/poplar/maple (honestly not sure what I got, or if I snagged a mix), is where the concern lies? I don't have much of it, maybe 12 boards total, so building a kiln/heating chamber is out of the question for me.

Is there a concern with milling and using these boards, prior to treatment, if they in fact are infected? Reason I ask, thinking I could make up several cutting boards (at least from the maple/white oak) and do the "heat treatment" after the boards are made, in the oven on lowest setting? I used to use the oven to dehydrate jerky (before getting a dehydrator) and would keep it propped open a bit to keep the temp at/around 135 since the settings didn't go that low...

Crazy idea to put wood in oven, maybe?
Would it actually work, not sure?
Would milling the lumber "spread" the beetles around my shop?
What do you guys think?

 

[CrealBilly]

This thread has got me worried now. It sounds as though the walnut, at least the heartwood is fine, nothing to worry about. Same goes for the cedar. The lighter stuff, whether it was the oak/poplar/maple (honestly not sure what I got, or if I snagged a mix), is where the concern lies? I don't have much of it, maybe 12 boards total, so building a kiln/heating chamber is out of the question for me.

Is there a concern with milling and using these boards, prior to treatment, if they in fact are infected? Reason I ask, thinking I could make up several cutting boards (at least from the maple/white oak) and do the "heat treatment" after the boards are made, in the oven on lowest setting? I used to use the oven to dehydrate jerky (before getting a dehydrator) and would keep it propped open a bit to keep the temp at/around 135 since the settings didn't go that low...

Crazy idea to put wood in oven, maybe?
Would it actually work, not sure?
Would milling the lumber "spread" the beetles around my shop?
What do you guys think?

Ive cooked small peices of lumber in a mirowave before. Not sure if thats a cure-all for PPB though. I did it to dry knife scales and pen blanks out. Worked pretty well as long you dont go to long and do it muliple times. No matter how much i cleaned up after myself the wife always knew i cooked wood in her microwave. Ofcourse i always did it when she was gone but got caught everytime.

Might be worth a little research to see if microwaves will kill nasty PPB. I cant say if it will or not...

I would not assume just because you see PPB exit holes in the sapwood and not the heartwood that the heartwood is not infected. PPB tunnel into the lumber lay eggs and exit so i would assume the heartwood is also infected.

What your seeing by the little piles of saw dust are the exit holes. The enterance holes are "usally" in the end grain and could have been made several years ago. Generally you dont see sawdust around the.enterance holes because the PPB eats that wood and leaves a white sticky residue as it craps out the wood it has eaten.

Have you ever ripped, jointed or planed a peice of lumber and seen a track mark of white sticky residue? Thats a PPB enterance tunnel. The can be very long also....

PPB are crazy wood munching and crapping machines, a few PPB are not much od a issue but a gang of them can spell trouble. Best to kill them with a sure kill (heat sterilization)

 

[KenOfCary]

Sent a PM to Scott - the expert here about heat treating my wood to relieve my anxiety. If that is not an option it will get disposed of in the woods around here. Just have too much other lumber to lose to not take this seriously. Not to mention the log house.

Now if only we can find some gas to get the wood to his kiln. When it rains it pours.

 

[thsb]

This is maybe the first time i have bought wood that wasn't kiln dried. it seems like cedar doesn't ever need the kiln drying? i was surprised to read that walnut is regular food for the beetles (i am guessing that is mostly sap wood) but i think a lot of walnut gets sold without sterilization.

If people buy kiln dried wood and then store it in a covered place outside and have it stickered, is that then safe to bring into the workshop if it has been outside for a couple of years?


i am thinking strongly about making a solar kiln, but then that would mean i would probably buy more wood, which at my rate of one piece of furniture every 3 months and no good place to store more than 200 bf of wood i am not sure it is a good idea.

 

[thsb]

i built a sterilization chamber, with 2 sheets of 2 inch foam board and another sheet of 3/4. if i had thought about it more then I would have been able to do it all with 2 sheets.

It seems to be working as the temp is showing around 175. I plan to keep it on all night (unless i stay up til midnight) as one website i read said that the Australian and European standard is 165 for four hours for every inch of wood.

I would have never done this if i hadn't seen examples of other NCWWers do it successsfully.

tim