How to kill wood eating bugs???

[Jeff Duncan]

Hi guys, I'm about to undertake something completely outside my realm of woodworking experience.....going to try and carve a log. I secured said log today, and it's a nice chunk of soft wood, maybe pine or similar, and while it's not fresh, it's not completely dry either. Looks like it may have been felled and left for a bit as the center is still pretty good, but the bark is gone and the outside is greyed already and covered with bug holes. It's roughly 22" diameter by maybe 28" tall, so not overly huge. Ideally I'd like to try and kill off the bugs but not sure if it's realistic. One thought I had was to put the log into a black contractors trash bag, seal it up, and leave it out in the sun for a week or 2. Just not sure if it would get hot enough to kill them? I've read that chemicals are pretty much useless and that you need heat to do the job, just trying to figure out a simple home remedy that might work....any thoughts????

thanks,
jeffD

[Jeff Bartley]

Jeff, I'm not sure how much help I can be but I've heard 160 degrees is the target temp and that it needs to be maintained for a period of time. I'd be tempted to build a small solar kiln. I think a contractor bag would lead to mold.
I did build a mini kiln for drying the ends of chair parts. It's super simple: cardboard box with a 60 watt light bulb, a thermometer, and a blanket to hold in the heat. You might be able to scale that up but I bet the risk of fire would go up proportionately!
I hope we get to see a picture of your carving when you're finished.

[Jim Andrew]

I have killed powder post beetles by putting the boards in a metal grain bin. Any metal shed you can close up will get hot in summer, as long as the sun reaches it all day.

[Mark Rice]

Give the log a good dose of Borax and put it in the sun and cover it with clear plastic. The temp will go higher with clear than black, believe it or not. Clear plastic is what the CSU Forestry department recommends for killing pine beetles over the black plastic. In about a week any bugs in the log should be dead.

[Allan Speers]

Heat definitely works.

Or, use Bora-Care. You can make your own for a little less $$$, though the amount you need is small enough that I'd recommend just buying a jug.

More info & also how to make your own:

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

[Danny Hamsley]

The target internal wood temperature that is required to kill beetles, their larvae, and any eggs is 133 degrees. It only has to be at this temp for a short while, but this temp is not the air temp, but rather the temp inside the piece of wood. I heat my lumber at the end of the kiln cycle to an air temp of 150 degrees and hold it for at least 24 hours to assure that I get 133 degrees internal wood temp.

[Allan Speers]

The target internal wood temperature that is required to kill beetles, their larvae, and any eggs is 133 degrees. It only has to be at this temp for a short while, but this temp is not the air temp, but rather the temp inside the piece of wood. I heat my lumber at the end of the kiln cycle to an air temp of 150 degrees and hold it for at least 24 hours to assure that I get 133 degrees internal wood temp.

Perhaps one could make a temporary foam tent (out of rigid insulation panels) then put large lightbulbs or a hair dryer, or even a space heater inside? Kind of expensive, though, unless you have another use for that insulation afterwards.

[Cody Colston]

Take it to a kiln. That's the only way to ensure you have all the larvae killed.

[Bob Bouis]

If I can offer a contrarian opinion: Do whatever you're going to do with it, and let it dry out. Bugs that were in the log when it was wet (it was wet, trust me) almost certainly can't survive after it dries out. They'll be gone soon enough.

[Allan Speers]

If I can offer a contrarian opinion: Do whatever you're going to do with it, and let it dry out. Bugs that were in the log when it was wet (it was wet, trust me) almost certainly can't survive after it dries out. They'll be gone soon enough.


Sounds like a bad idea to me:

First, PPB larvae survive just fine in dry wood.
Second, if you use the wood for a project, when the larvae later hatch they will destroy your finish.

[Bob Bouis]

There are two kinds of "powderpost beetles." One eats wet wood only. The other, which is far less common, eats dry-ish wood, but only the sapwood of hardwoods.

And, yeah, the bugs might exit the wood after he carves it, but it was already decayed when he started. Plus it's going to crack and warp anyway as it dries.

[Jeff Duncan]

Thanks guys for all the advice. Right now I'm leaning towards the foam panel box, (mini kiln), idea. Someone else had suggested I could have mold problems if I just seal it up in a bag for a week, and that's just another problem I don't want to deal with. A foam box with a high wattage bulb or 2 should do the trick in this weather. Only concern is leaving it overnight. Not sure how long it would take the inside of the log to heat up, but surely a fairly good amount of time. Though on the same token I continued shaving the log down towards a square for carving this weekend and seems as though the majority of bug tunnels are within the first inch or 2 of the surface. Once I got to the "fresh" wood it was pretty much untouched. Also found at least one of the current tenants are small carpenter(?) ants, they came out to investigate what the noise was and unfortunately for several of them....found out it was my power plane:rolleyes:

JeffD

[Scott T Smith]

There are two kinds of "powderpost beetles." One eats wet wood only. The other, which is far less common, eats dry-ish wood, but only the sapwood of hardwoods.

I have seen lots of PPB exit holes in the heartwood of red and white oak.

[Danny Hamsley]

They love hickory and ash, too.