Air dried wood bug problem

[David Gilbert]

I stumbled upon a stash of ambrosia maple stumps that were split and then air dried in an unheated and uncooled storage unit for several years. Some of my friends saw these large blocks as fire wood and they may still end up being used for that. I cut up several pieces and many of them have beautiful tiger maple figure when quarter-sawn. I band-sawed out several test pieces, hand planed then and applied a Danish oil. These will make lovely boxes or drawer fronts. They are beautiful but after a week in my basement they have accumulated some dark grit on the surface. Apparenty I have some small borers or other insects that have come back to life in the warmth of my basement and are happily munching on the wood. Their residue is very small, probably about 0.025 inches in diameter.

The holes they leave are almost invisible but I'm not very happy about the prospect of these bugs continuing this process on my finished objects. Does anyone have any suggestions to kill these little bugs? I can think of several methods but most appear to have serious impacts on either the wood or on the health and safety of the owner.

Thanks,

[Rob Will]

130 - 140 degrees for 3 hours.

Rob

[Cliff Rohrabacher]

What Rob says.

I am going to do exactly that this summer.
I have a bunch of maple that I was too lacy to debark in time to prevent the little pallies from getting to.

I'm going to set it on blocks in the sun wrapped all around in a black plastic tarp and leave it there for a week or so.

I am sure that such unkind treatment should heat the innards of he logs enough to kill the bugs. I may add something special to the mix to make sure. Chlorine gas in the form of some 12% pool bleach in a couple of pans might make for a good time in the old town in all them bug burrows.

[Jim Becker]

Boric acid.

[Greg Cole]

If that wood is in your shop, I'd get it the heck out of there ASAP then worry about killing the creepy crawlers.
FWIW, I have some spalted curly maple I made a set of bookmatched door panels from that are absolutely GORGEOUS that came from an uncles firewood operation. Now that I am an avid WW'er I cringe at the amount of this kind of wood that I split working for said uncle.... Too bad I'm 1500 miles away from him now as I'd have access to more that I'd know what to do with.

Greg

[Cliff Rohrabacher]

Boric acid.

I treated my entire 250 year old cellar with a home-made batch of the the stuff and haven't seen a creepy crawly since. We used to have regular invasions of the grubs and moths.

However, the stuff is only good on the surface ('cause it doesn't penetrate much) and then only when they are chewing through it. Inside where they are tripping the light fantastic the only ways I know of to kill 'em are radiation, gas, or heat.

I can do gas in the form of chlorine and heat together.
My license with the Nuclear Regulatory Commission hasn't been processed yet so I can't get that chunk of Cobalt 60 I have wanted for so long.

Here's a question Jim:
If you treat your work with a water based boric acid solution and then final sand and finish - - will the acid negatively effect the finish?

[Gary McKown]

From what I have read the "ambrosia" in maple is not caused by powder post beetles or the like, but a different variety of wood insect. Your description of the small holes fits the bill. Apparently the holes do not much affect strength, etc., either, unlike the PP tunnels.

I know boric acid (plain or one of several brands) will kill PP larvae, but don't know if it is effective against Ambrosia beetles. I think enough heat would do them in, provided it does not mess up the wood too much. Something simple like soaking in denatured alcohol might work, too.

[Tom Godley]

How do you do the boric acid treatment??

That was always the standard product used dry for roaches in New York -- and steel wool to close up any holes.

I purchased a few masks overseas on a trip a couple of years ago - hung one in a bathroom and noticed sawdust on the counter-!!

I did not know what to do to get rid of them -- I ended up dropping some mineral oil down the few little holes with a syringe.

[Greg Cole]

FWIW, If you are sure the critters are the true ambrosia beetle they should be long gone as they infest a tree as soon as its felled or right after the tree dies.
Gary,
Ambrosia maple is named after the beetle tunnels in and releases its fungus as it bores in. The fungus is what causes the color variations.

Cheers.
Greg

[Brad Sperr]

If the pieces are small enough, could you also go to the other extreme and stick them in the freezer? I know that this is a good way to kill any boring insects in cigars.

[David Gilbert]

I don't know what these bugs are. I tried to dig one out but couldn't identify anything that looked like a bug. They are very small. I've seen borers in hickory and beech and the holes for in these boards are about 1/4 the diamaer. I doubt that these bugs are the cause of the darkening. This wood is quite dark and next to where the hollow of the tree was it is darker than walnut. Because of this I think the ambrosia bug or fungus has been there for a long time while the tree was still growing.

Of the suggestions so far, I like the 130-140 degree for 3 hours the best. These boards have been frozen for most of the winter so I doubt that the freezer will work. (By the way I will add borers to my list of reasons for not smoking cigars!).

Thanks again,