Looking for the life story of White Pine grubs - Anyone?

[SwampDonkey]

What? No Coffee? ;D

Those critters can do a lot of grubbing in a short while. I sat on fresh cut logs before and seen those mean, nasty devils scouting the pile for chance to lay an egg.  Crunch, Crunch, Crunch, Crunch.

[jackpine]

I have a question about sawyer beetles. I have been re-sawing some pine 2 x 6 ( splitting in half to make 1 x 6 ) that have been sawn at least two years and I have uncovered several adult beetles still in the wood that then crawl out, shake themselves off and away they go if I don't get to them first ;D My question is, how can they live in this dry wood as I thought that once the wood dried out they would no longer feed and thus die. These were BIG and showed no ill effects of being trapped inside a 2 x 6 in a pile of lumber :D

Bill

[Tom]

The inside temperature of the lumber never was brought high enough to kill them, as in a kiln.  The inside of the air dried lumber probably never went lower than 16 percent, 12 at the least.
The insect's aren't eating the wood, they are metamorphing (pupating) from a grub into a beetle.  It's like a hibernating bear.  All they need is contained within their bodies.  To come out, all they would do is change the entrance hole's shape to fit their new body, making an exit hole, and crawl out. Entrance holes are oval and filled with frass (sawdust, slivers, excrement, etc).  Exit holes are round and clear. 

A Sawyer woudn't lay eggs on your 2x6, she would go to another stressed tree, or one that was down.  She would lay her eggs in a divot in the bark and it would all start over again.  They feed on the cambium under the bark.

[jackpine]

Tom, I understand that but my real question, if I had asked it clearly, is how long can the adult live in the wood after it hatches? It is not eating at that stage regardless of the moisture content of the wood so one would think that eventually it would die. By the way, these were some of the largest beetles I have seen and they certainly still looked healthy.

Bill

[SwampDonkey]

Black with long antenna? I've never seen any live that long in sawed lumber. I have taken pine in to mill with the grubs into it. Sawed it out that day and came home to stack it and after a couple weeks I went to the pile and saw where the adults had came out leaving little piles of sawdust. I don't know when they emerged, but sometime in that 2 weeks anyway. Sure there was no new stuff stacked on the pile?

[mike_van]

Not sure Bill, maybe you're too close to 'the frozen tundra of Lambeau Field?'  :D  I've never had any hang around that long once the lumber is cut & air dried.  Slab piles, though - If they never get to dry, might be a good home.

[Tom]

Jackpine,
I've looked through all of my available entomology books and searched the web.  while there are defined studies, these documents only lead me to others, which I will have to find.

To give a general opinion depends on the beetle. Southern Pine Sawyers produce three or more generations a year. 
The white spotted borer, in the north, takes two years to complete its life cycle and, as best as I can figure, overwinters as an adult, inside of the tree, exiting in the spring of the following year.

Given that it takes 4-6 weeks for the larvae to leave the cambium and begin entering the wood of the log, both of these time frames would give an ample period to find adults in air-dried lumber.

[shinnlinger]

I just saw on the history channel that although Mr Stihl gave us the chain saw, it was a dude in the mid 40's who looked at the curved mandibles on a grub in his wood pile that gave us the modern chain with the curved teeth.

I had a huge wind storm here April of 07 and there are some nice sticks still out on the woods and I am emberrased to admit, in my wood pile.  I have recently started sawing with furver though and am on a first name basis with almost all of these creepy crawlies.  That said I have been turning the blustained bug riddled sap wood into 2x stock and findiing excellent wood in the core.

Is there a limit to how far these guys penetrate?  Do they just hang under the bark and sap wood?

Should I spray my sawed lumber?  It seems that once it dries out the bugs go away, but most of these boards are going to end up being used somewhere on the property.

[Tom]

Spraying wouldn't hurt, but isn't usually necessary unless you are trying to prevent the infestation, or re-infestation, by adults laying eggs.  Power Post Beetles is an example

Be cognizant of where the wood will be used when you spray.  A lingering insecticide on a table or wood used in a baby's crib might not be prudent. 

Most borers penetrate about 6 inches and then turn in a "J" to face the outside of the log for pupation.  Other insects can, and will, riddle a log, beam or board.

[mike_van]

I used a lot of grub holed pine for barn siding. Latex caulk fills the holes, Cabots solid oil stain afterward. My slab piles get big enough without throwing good sound boards on them.  De-barking, keeping the logs wet, [not real practical for most of us] or sawing them up are the best ways I've found to keep them out.

[shinnlinger]

Tom,

I am impressed with your knowledge on this and many other subjects.

Thanks for sharing.

[Tom]

Well, thanks.     You'll get there too.  I just started reading before you did.   :D :D  that's the fun part of life, being able to pass on info.

[RSteiner]

Bass love those grubs!  If you're going fishing.

Randy

[SwampDonkey]

Can't waste.  :D

[moonhill]

The pine borer as I call them are a constant issue.  The don't really bother me it's the client who precieves them to be bad.  It would depend on the scope of the project as to weather I would use or not use buggy wood.  Exposed timbers in a frame I have no problem using, this based on the historical fact that they used buggy wood in the past.  Why not today as well, are we better than our ancestors that we should have every thing perfect.  Wood is not perfect, it checks, it has knots, pitch pockets, it swells in the summer and shrinks in the winter, it rots, bugs infest it the list could go on.  Some of us just want it perfect, clear, free of checks, no blue stain and no bug holes.  Ever wonder where the term "coming out of the woodwork" derived from, I think I know.  You can even find distressed furniture in the big stores but if it was naturally occurring buggy wood "OH NO" we must be in control.

In a perfect world I would have all my sawing done by May 15th with a 2 week grace period, but this isn't a perfect world.  I may not have all the facts straight but here is some of my ways to avoid bugs and blue stain.  Saw the wood before the temp rises above 70 degrees and has enough time for the moisture to drop some.  Soak the logs in a river or pond and as mentioned earlier under a sprinkler.    Peel the bark, although if I had the time to peel I would saw them instead, this may help with the bugs but not stain.  All these things change the perfect environment the bugs of fungus need to live, too much water, not enough water, the right temp 70 or up.  I haven't tried this but wonder if a big tarp covering the log pile would keep the bugs at bay.

Another thing I have noticed is the flitch piles.  The bark is still attached, it's waiting for the edger, they sit for 3 years some times and bugs have gotten into the the layer just under the bark and turned it into powder, after 4 years I see no bugs, 3 or less bugs still there.  This flies in the face of the moisture issue, maybe it's a different bug I don't know.  They leave the same tracks as I see in the cellar beams of an old house.   If they are edged no bugs, I've removed their environment.

Swampdonkey, Do you know what the adult ambrosia beetle looks like? Are they the small brown barrel shaped bugs, about 1/4" long?  The fungus pod they grow is wierd, almost like a puff ball without the skin.   Tim B.

[SwampDonkey]

Ambrosia and Engravers