Ambrosia Beetle Problem

[Wiley's Woodworks]

I recently made a bookshelf set out of ambrosia maple, and had an ~6' slab left over. I stacked and sticker it in my outside wood storage. Moved it today and discovered 20-25 little sawdust piles on the board underneath it. I inspected it and could see new beetle bore holes. I took it off the pile and set it off by itself. How do I kill the beetles that obviously are in the wood? Do I just throw it away?

I'm not concerned about the piece I made from the other end of the board because it was milled extensively and finished with 4 coats of Danish oil. I'm assuming (hoping) that the processing killed off the beetles in the finished bookshelves, but if someone knows differently, let me know. Last thing I want is a dissatisfied customer.

 

[wndopdlr]

Because I am always hauling in wood from unknown sources and most of It I air dry, and because my wood is stored in an enclosed trailer, I set off bug foggers in both my wood shop and storage trailer at least twice a year. No problems with boring insects in over twenty years.

 

[Oka]

I do something similar. I make a cheap plastic make shift tent and set 2 off one on each side.

 

[cliff56]

What type forgers do you use?

 

[chris_goris]

A topcoat on a finished piece will generally not kill internal beetles. Your customers may start to see sawdust.... Heat treatment typically will though, maintaining 130 deg for 5 days or so, I believe is recommended. You could try boracare as well. I would probably just pitch it. This is why I only deal with Kiln dried wood anymore.

 

[Rwe2156]

Was it kiln dried? Ambrosia maple by definition is beetle damaged.

The only way to kill them is heat, either a kiln 140°, or a fire. It is serious business. They will attack soft wood first. I've tossed my share of beetle damaged lumber in the fire, as I want it the heck out of my lumber room!

External treatments will not work as the larvae are already in the wood. You will see sawdust when beetle larva emerge as adults, this mean you have an active beetle infestation. The rest of your wood is either damaged already or certainly at risk.

This is the risk in using air dried lumber. The safest way to go is right off the mill, either kiln dry or Borate treatment right away.

I hate to say this, but larva can emerge as adults up to 4 years later. Painting or finishing doesn't matter either. I've had a very unfortunate experience with this, 2 years later the wood is pocked with holes. I even found adult dead flies on the floor. Not totally my fault, the wood came from a sawmill and assumed it was kiln dried because they had a kiln. I found out later that kiln drying is an "extra".

 

[Matt Furjanic]

I did this on a table I made. I’m not endorsing this as safe, but it works:

put it in a large plastic bag, and dump a can of boric acid in there. Let it sit for a few weeks, then wash it thoroughly with soap and water. Bye bye bugs…

 

[Rwe2156]

I think the bugs were already emerged. I’ve tried everything the only thing I think works is cooking them.

 

[wndopdlr]

Interesting to read comments from those that say the foggers will not work. I store cherry, RO, WO, hickory, pine, cedar, walnut, butternut, HM, SM and curly maple all in the same converted car hauler trailer. Some of that wood has been in there for ten years or better and I do not have any of the tell tale sawdust signs in my wood racks.

Either the foggers do work or beetles haven't found my stash for twenty years which is unlikely. To answer Cliff's question, I use the Raid brand foggers and set two off in the trailer twice a year.

 

[Rwe2156]

They haven’t found your stash. You’re talking oranges and bananas. The wood is in a trailer its protected, not stickered outside in a shed, and how hot does it get in there? A fogged is only going to affect whats in there at the time.

If the wood was exposed you would probably have a different experience.

If you read on the biology of the beetles, you have to prevent them from getting in. The most efficient product are borates or any I’d the termite products used in construction - something that stays there and doesn’t affect the wood.

Once the larvae have bored inside half the battle is lost. At that point the only way to kill them is heat. No insecticide is going to penetrate enough.