I have a walnut slab I bought about 15 months ago in northern Illinois and have finally begun working on it. When the bark was removed, it revealed the feast a host of critters had. To my surprise, as this is my first time working with a slab, I’ve found a handful of larvae munching away.
The attached pics show the culprit. One pic reveals what I didn’t see before, and that’s another culprit my camera caught.
There was a lengthy discussion on this topic in a 2006 post, but it mostly centered on the Powder Post Beetle. Not sure I’m dealing with the same thing. I also have not seen any signs of it on the large supply of cherry that it was near.
Anyhow, looking for suggestions on how to deal with this, including having it become an expensive piece of firewood.
Replies
Termites ---mostly in the sapwood right? I would treat the slab with something like boracare or use the slab for firewood. Well , I'll take that back. I would remove the sap wood and if there are no channels going into the wood I'd think maybe I got them. Treating the wood is still a good idea.
There are many different kinds of wood boring beetles and grubs. I am not an expert on the types, but there are many where I live in Arkansas. My experience is that they love wet wood and especially sap wood of lighter colored woods like sweet gum, sycamore, and the sap wood of other darker woods. One key thing is to dry the wood out as soon as possible. Another is to cut away the parts where they have bored. If you get to them soon enough, you will save most of it.
Hmm. It's a narrow slab already, so cutting away the sap wood essentially renders the piece unsuitable for what I was preparing it for.
Incidentally, that bug is about 1" in length. I didn't know termites were that big, but I'm not even at a pre-K level on that sort of thing.
The price of bora-care is about the same as what I paid for the slab, too, so it doesn't seem to be an economical approach. Thankfully, I'm not married to the slab.
I'll chalk this one up to the cost of experience in selecting a slab, and for waiting way too long to inspect it (aka, remove some bark.) I'm sure that if I can't salvage it as a slab, I can mill it and use the good heartwood for another project.
Do others routinely treat their slabs, or is this done only when there's evidence of unwanted residents?
Except from the pictures those look like termite larva just prior to growing wings and becoming bugs (adults.) Drywood termites ,which unfortunately, I am way too familiar with swarm out usually in the late summer/ early fall. Different climates different schedules maybe.. They shed their wings mate and start looking for new homes. So, what your looking at in that wood is a second generation at least.
Boracare is this great product, safe to use, it's borax basically in a glycol solution. The glycol is the difference from other borate termite products.. The glycol penetrates deep into the wood and the borax kills the bugs. It doesnt wear off or out so the wood is termite proof forever, or so they say. Also works on powder post beetles. The penetration is such that they use it on log homes. Personally though active bug damaged wood goes in the woodstove. I have no idea how treating wood this way reacts to finishes though I would think that a straight up oil finish might be ok.
Except from the pictures those look like termite larva just prior to growing wings and becoming bugs (adults.) Drywood termites ,which unfortunately, I am way too familiar with swarm out usually in the late summer/ early fall. Different climates different schedules maybe.. They shed their wings mate and start looking for new homes. So, what your looking at in that wood is a second generation at least.
Boracare is this great product, safe to use, it's borax basically in a glycol solution. The glycol is the difference from other borate termite products.. The glycol penetrates deep into the wood and the borax kills the bugs. It doesnt wear off or out so the wood is termite proof forever, or so they say. Also works on powder post beetles. The penetration is such that they use it oOK. og homes. Personally though active bug damaged wood goes in the woodstove. I have no idea how treating wood this way reacts to finishes though I would think that a straight up oil finish might be ok. An adult termite can be an inch long. Ground contact termites can be much bigger. Some exotics /foreign visitors bigger yet.
I appreciate the informed insight and experiences. Looks like I'll be turning my attention to a cherry slab I have that shows no signs of unwanted inhabitants. And to inspecting my basement where this was stored!
To be honest, I don’t do anything when I find bug holes. I blow out as much sawdust as I can, cut off as much of the sapwood as I can and just go with it. I have had one project where the bugs came out later, but that had no finish on it and they died shortly afterwards since my shop gets sprayed for bugs since my dad is adamant about it. However, at home, we use no pesticides and have never had a problem. Could be that we don’t have the more difficult species of critters in Wisconsin. Some people around here even like the worm chewed look. I have a rolling pin that a guy made. It’s all filled with holes. He cleverly filled the holes with glue and various shades of sawdust to make a cool contrast look.
If your more extreme, you could do like my dad does and soak it with red dyed diesel fuel. Don’t ask me why he thinks it’s a good idea….
I have been making charcuterie (sp?) boards from a piece of cherry that has been sitting in the rack for 15 years. It is a beautiful and unusual piece that has the core wood discolored by minerals; it looks a lot like olive. I never used it because it was twisted. Being about 1 1/2" thick, I hand planed it flat and the result is beautiful. There are similar bug tunnels on the edges. I filled them with epoxy, thinned with a couple of drops of acetone to improve the flow into the tunnels. They turned out fine, the iphone photos are too large to post.
This is unlikely to be termites, unless the slab was lying on the ground, or had proximate ground contact. These are almost certainly a species of boring beetle. The adult female lays eggs in cracks in the bark, the eggs hatch, and the little larvae start eating their way into the wood. The larvae have different preferences for their diet, but most species really don't like the heartwood of the species with rot and insect resistant heartwood, which includes cherry and walnut. The one sure way to kill all the living larvae in a piece of wood is to kiln dry it; the heat and dryness does the trick. I'm not familiar with Boracare and how effective it might be. Just painting on with a brush would not seem adequate for the amount of penetration needed.
If you want to use the slab, remove all the bark, get it dried, and fill the holes with your filler of choice -- epoxy mixed with sawdust would probably be my first choice. These days, many folks would use epoxy or casting resin with some bright color dye added, to make the holes a feature. And in the future, remove the bark immediately from any slabs...
I can tell you disregarding them is risky. I had emergence holes appear 3 years later in the doors of a built in. Lots of repair work
Bora care won’t work on an active igestation it’s a preventive. Kiln drying is the only option
Firewood. I wouldn’t use it.
That brings "live edge" to a whole new level!
Live edge, indeed.
In for a penny, in for a pound. I've decided I will fill all the holes with epoxy. I'm ok with the distinctive look, after attempting to determine if they have anything living in them. Maybe I'll squirt some mineral spirits into them.
This project is only for elevating and expanding my skills, which gives me the latitude to risk it. Using epoxy is one of those skills. It will become an entry table that I'll seal well, then monitor over the next few years. If it has to become firewood later, so be it. I'll detach the base and fashion a new top.
JHarveyB's assessment is more likely, that it's a boring beetle and not termites. The patterns below the bark line, and other holes suggest this. It's all mostly contained to the sapwood, of which there's a bit too much, it turns out.
Soaking it with red dyed deisel fuel? Um, I think I'll pass!
Bowl rough turned from an 🐜 ants nest two years ago, the ants would climb out as I removed wood, I would spray with Raid and resume turning , filled it with epoxy after drying and now ready to go back on the lathe two years after roughing out.
Filling in the holes will do a lot for filling in the holes but you have a live infestation. You know this because you actually saw the bugs. Timb0r, a borate product, is a preventative. Boracare will kill an active infestation, it's the glycol that creates the absorption. The same stuff they use to preserve the Viking ship that they dig out of the river bank to stop it from disintegrating when it hits the air. The insect eats the borax and brings it home to the whole colony. The manufacturer claims very deep absorption with their product..and claim its permanent. They're are poisons available,, one I've used is Premise Foam. You pump it into the channels, kills anything that it comes in contact with and is temporary..
Subterranean termites come out of the ground and are a particularly nasty animal. They work from the bottom up. Drywood termites do not ,they fly from place to place and establish new colonies. They love rafter ends where I live. They are more from the top down. Here ,where I live, drywood termites are a continuous problem. You tent your house but on the next life cycle they will reenter and begin establishing colonies. In a few years, 8 to 10 , theyre at a point that they're causing noticable damage and you tent again. They will eat a stud wall down to paper given enough time.. I have the foam and I have the boracare and I treat where I see termite droppings but those are the ones I see. They're winning the battle at this point. I'm going to have to tent here again soon. It's a huge PIA to tent. Its expensive ,you have to do stuff with all your food and dishes. Depending on your level of concern maybe your bedding needs removed, though the tenting guys say you dont need to. Then you have to get lost for a few days.
Introducing insects into your home via a coffee table or something doesn't seem like a good idea. When I've tented I bring all my wood from my sheds and stack it inside, just in case.
Closing the loop on this, I took a hybrid approach rather than unnecessarily burn good heartwood. I used a circular saw and trimmed off 1" or so pieces in areas where there were holes. I continued this until there was no evidence of further boring on any edge.
I did find one additional live creature about an inch in and an inch away from heartwood. I also found a dead beetle, long decayed.
Left for me is some decent wood that I can mill later for another, TBD purpose. The sapwood is headed to the fireplace.
It was a good learning lesson, especially for any future effort to select a decent slab.
This forum post is now archived. Commenting has been disabled