Question about milling beetle kill trees

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Judson

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So here in northwest colorado we have an abundace of trees that have been killed by mountain pine beetles. Most are lodgepole and spruce, with some vary large firs mixed in. I was planning to cut a select few and mill them up for wood working projects, some beams for a shed and so on. What trees would be the best for milling? is there a way to identify a tree that is going to be full of fungus or rot? Are there structural issues with trees that have been killed by beetles? Thanks for all the help.
 
Judson I don't know enough your area of the country, or about beetle killed softwood trees in general to answer your question. We don't get much of that here in the east coast. I think it would depend on how the beetles kill the tree. If they just defoliate it for a few years, like our gypsy moths do here in this part of the country, which sometimes then kills the tree, then the lumber is still sound. Obviously, if they bore into the tree and its riddled with tunnels, it's not going to be as structurally sound, but then thats not news to anybody.

sorry I can't be more help... but welcome to the forum. Any questions about milling those logs, ask away.
 
Most of the trees have died due to the widespread dryness that has affected colorado for the last several years. Most of the beetles are bark beetles so the are not of the wood boring type. They do impart a blue stain on some of the wood, typicaly the sap wood.

I guess another major concern is the fact that some of these trees have been dead for 2 or more winters. Will this make them very hard to mill due to how dry they will be?
 
Welcome to the site!

Having milled some beetle-killed Ponderosa Pine, you will find some very interesting natural stains, from charcoal grays to purple - blue shades in the wood from a secondary bacterial proses As it is very sought after for finishing trims and interior projects, I don't know how much of a structural hit it takes, as the bettles kill the trees from the bark, and don't bore the wood (I'm thinking not much) there is a chance that Larry The Cable Guy will be able to answer that?

(I will see if I can find some pictures of some of the color patterns and post it?)

Edit: well I guess you knew that!
 
Last edited:
I don't really know the answer. We have a LOT of bark beetle kills here too.

From what I understand the bark beetle problem is secondary to drought. In "good" (non-drought) conditions the trees can normally ward off the beetles with sap. When the trees are weakened by drought they can't produce enough sap to keep the beetles under control.

I have seen quite a few trees that were really rotten in the center but I have no idea how long they were standing dead before they were taken down and what types of secondary/tertiary organisms or disease processes may have caused the decay.

Hopefully someone will speak up and set me straight here.

.
 
You guys have it basically right. Bark beetles kill trees that are stressed, unless the beetles' population really takes off (an outbreak) and then they kill trees in any condition. It's the resin that chases out the beetles if they attack in low numbers; lot's of beetles (such as mountain pine beetle) overwhelm the defense. A successfully attacked tree has hundreds of "pitch tubes", blobs of resin mixed with sawdust where the adults pushed out the resin and sawdust from their tunnels. Adults tunnel in and lay eggs; the cycle is complete after a year when the new generation emerges, peppering the tree with thousands of exit holes. Some species (such as red turpentine beetles) can infest patches of bark and reproduce without killimg the tree. A tree usually has several species of bark beetles in it, in addition to associated insects that come along for the ride.

Bark beetles only feed on phloem (inner bark), and just score the surface of the sapwood. The same year they are killed, wood boring beetles (roundheaded borers, or long-horned beetle, and flat-headed borers, or metallic wood boring beetles) and wood decay fungi enter the tree. These other beetles, as larvae, feed on phloem at first, but then head into the wood. A couple months after bark beetlle attack, ambrosia beetles (shot-hole boreers) head into the sapwood, making very tiny width holes; they leave lot's of white, fine sawdust on the outside of the bark, because they bore in the wood, and there is no resin left because the tree is dead (although the foliage may still look green).

The stain is caused by fungi tha just break down the sugars in the sap. The trees will degrade fairly quickly, but not all at the same rate; a lot depends on the activity of the "associated" critters, not the bark beetles themselve. I have seen 18 in. ponderosa pine blow over 2 years after beetle kill due to termites and wood decay fungi! OTH, trees may stay relatively sound and up for several years. It seems to me that on drier sites, the beetle killed trees last longer; however, I've seen big western white pine in relatively moist forest stay sound for years, identifiable by their perfectly columnar white trunks, with the bark completely off.

When beetle kill is salvaged, if the log stays together, it goes on the truck (for pulp). The relatively new market for stained sawn lumber probably comes from trees felled in the same year that they are killed, so that wood decay and large diameter tunnels from wood boring beetles hasn't occurred yet. Unlike timber salvaged from a fire, I would say that after 2 years, forget about it--it isn't any good for dimension lumber, decorative or not. The test is in bucking up the tree.

Some species:

Mountain pine beetle (Dendroctonus ponderosae): ponderosa pine and jeffery (small trees), lodgepole, western white, whitebark, sugar

Western pine beetle (Dendroctonus brevicomis): ponderosa, jeffery pine (large trees)

Spruce beetle (Dendroctonus rufipennis): Engleman spruce, black spruce

Southern pine beetle (Dendroctonus frontalis): Longleaf pine, Shortleaf, Slash, Loblolly

Douglas-fir beetle (Dendroctonus pseudotsugae): Douglas-fir

Fir engraver (Scolytus ventralis): Grand fir

Basically, every conifer has one or more bark beetles that kill them. Cedars, Sequoias, and Hemlocks rarely are killed by bark beetles.
 
what he said

What Doctor Dave said .....
Pretty detailed, would disagree on one thing.

"The relatively new market for stained sawn lumber probably comes from trees felled in the same year that they are killed"

That market is fairly old. Blue stained Ponderosa Pine and some LP, typically tongue and groove 1 x 6 boards, have been used for a very long time. I put up a wall of it in 1981 or '82 and it had been around since Hector was a pup even back then.

I have been told that the blue stain is the start of rot, but that the wood is still fine structurally. My experience working with this blue stain Ponderosa Pine verifies that. However, I have not seen that wood used for 2 x 4's. Just the decorative tongue and groove.

(At higher elevations in Colorado, Lodgepole can live over 250 years commonly. Around here, it is usually an 80-120 year tree. Mountain Pine Beetle is the most common cause for its demise.)

{There is a debate ongoing among some scientists whether the bark beetles kill the tree by girdling it or if it is really the rots that piggyback on their bodies that do in the tree. At least one study is ongoing where some beetles have been sterilized to compare with rot carrying beetles and check the tree mortality rates.}
 
Judson said:
I guess another major concern is the fact that some of these trees have been dead for 2 or more winters. Will this make them very hard to mill due to how dry they will be?

I've been milling some dry (been down for a couple of years) Cupressus Macrocarpa which is quite a durable species from North America. The only negatives I found with such dry timber was some splinters coming off the sapwood and alot of dry sawdust blowing everywhere. The heartwood was perfect, the wood dry and light (relatively, they were slabs 14' x 36' x 2 1/2"). I guess the only way to find out, is to keep dropping trees until you find a good solid one, buck it into the lengths you want and if it looks good right through go for it:greenchainsaw: Starting with the trees that are naturally durable will give you a headstart
 
smokechase II said:
What Doctor Dave said .....
Pretty detailed, would disagree on one thing.

"The relatively new market for stained sawn lumber probably comes from trees felled in the same year that they are killed"

That market is fairly old. Blue stained Ponderosa Pine and some LP, typically tongue and groove 1 x 6 boards, have been used for a very long time. I put up a wall of it in 1981 or '82 and it had been around since Hector was a pup even back then.

I have been told that the blue stain is the start of rot, but that the wood is still fine structurally. My experience working with this blue stain Ponderosa Pine verifies that. However, I have not seen that wood used for 2 x 4's. Just the decorative tongue and groove.

(At higher elevations in Colorado, Lodgepole can live over 250 years commonly. Around here, it is usually an 80-120 year tree. Mountain Pine Beetle is the most common cause for its demise.)

{There is a debate ongoing among some scientists whether the bark beetles kill the tree by girdling it or if it is really the rots that piggyback on their bodies that do in the tree. At least one study is ongoing where some beetles have been sterilized to compare with rot carrying beetles and check the tree mortality rates.}


"Relatively new"... I've been told that I'm mired in the 70's based on wearing some tight clothing. As far as decorative paneling goes, I guess it depends on local supply and how much local lumber dealers want to push the product. I rarely have seen it, except randomly mixed in to one-by pine boards (based on Seattle, Portland, The Dalles, and Hood River). It may be a special order in some lumberyards, and just not on display.


I year ago, I saw a wall unit/entertainment center that had been made custom for someone, made entirely (and purposely) out of blue-stain pine. I would assume that the cabinet maker ordered the stock.

About what kills the tree...I haven't read the latest research on the beetle, but old conclusions are (and should be) challenged. Based on a lot of reading I did in the 90's, the tree basically kills itself. Before the phloem and cambium are completely girdled and/or removed, the tree attempts to respond to the invading fungus carried in by the beetle through lysis (cell death) in a zone around the borings where the fungus is introduced (fragments of it stick to the bodies of the adult bark beetles when they emerge from the trees they matured in). This is an active response by the tree, kind of like a runny nose when you get the common cold. Technically its called a hypersensitive induced response--the tree recognizes fungal cell wal componds. The resin and dead cell contents plug the tyloses (pores) of the tracheids, the vascular cells, and the sap ceases to flow; this also blocks fungal mycelia (the microsopic threads of fungus). Because most of this action is going on in the trunk, the branches can stay green for 1-3 months; by the fall, they will look yellow-green.

So, if many beetles attack a tree at once, producing an entrance hole every few inches, and a vertical egg gallery up to 3 ft. long, it is easy to see how the tree would rapidly have little sap flow and essentially be dead. The process is not reversable. About the argument, I thought that it was an artifact of incomplete understanding of the process from back before the hypersensitive induced response was well understood.
 
All this info has been very helpful. I will just have to go and get a close look at some of the trees. Any good indicators on a standing dead tree as to the condition of the wood inside?
 
Smokechase, Dr Dave, VERY interesting info... it never ceases to amaze me how much talent this forum has. Many on here have at least one niche that they are good at, and willing to take the time to spill. Really interesting about how the tree kinda kills itself by over responding to the infestation. Common theme among living things, as our body does the same thing sometimes, as Dr Dave mentioned as per catching a cold.

You said two years and the tree is often toast, too far gone. It always amazes me how fast the borers here in the east can tunnel deep into a dropped 36" dia solid oak or pecan tree. Once it's on the ground, it doesn't take long before the trunk is full of beetles.

thanks for your input
 
beetle questions

Doctor Dave:
I've noticed in some sunny areas where the beetle hits (pitchy entrance exit holes) may be 10 or 30 to one on the shaded side of the tree.
Indicating possibly that they can't take the heat.
Anything to that thought?

I remember some folks in La Grande in the 70's that were wrapping their Pondos main stems with black visqueen. I wonder if that was related .....

Back to the milling question. Sorry for the thread Hi Jack.

I'd think an appropriate use for blue stain Pine from the home lumber end would be to make a rustic looking beam out of something else. You know what I'm talking about. A high ceiling home has steel or nailed together 2 x 10's for a beam.
 
smokechase II said:
I'd think an appropriate use for blue stain Pine from the home lumber end would be to make a rustic looking beam...
I for one would love to have rustic looking blue stained beams on my ceilings. Each one full of character, no two alike. I found a 17ft long Doug Fir 9x9 timber, sound, no nails or holes, naturally beaten up from the river, floating down one of our larger rivers here. I managed to get it home, shortened it a bit, sliced it in two on the bandsaw, and it has hung across and above our bay window for the last 15 years. Plants hang from it, a nice rustic look.

What I have never figured out is where it came from. Doug Fir doesn't grow in the east here. Where did a beam that size WITH NO NAILS OR HOLES come from? All I could think of was that it was once part of a bridge that busted up, but again, then it would have metal in it somewhere, or holes for hardware. It had neither. Mystery.
 
I was hoping to use it in a way that would accent our new house and use some of this wood that we have that has died over the last couple years. To give an idea of how bad the beetle kill areas are, I went for a hike this summer and for nearly a mile every tree except aspen was dead. I will post a couple pictures shortly of some of the hillsides that are compleatly dead due to the mountain pine beetle. I know it is a natural process and all, but I just hate to see all that wood go to "waste".
I was first introduced to using the blue stained wood when a client of mine purchased a door at a home show and then wanted me to design a house around it. It was a beautiful door with blue and red hues in it. They also paid over 5000 dollars for it, so I can only assume that it must be hard to get the wood that looks so nice from a beetle kill tree.
 
smokechase II said:
Doctor Dave:
I've noticed in some sunny areas where the beetle hits (pitchy entrance exit holes) may be 10 or 30 to one on the shaded side of the tree.
Indicating possibly that they can't take the heat.
Anything to that thought?

I remember some folks in La Grande in the 70's that were wrapping their Pondos main stems with black visqueen. I wonder if that was related .....

Back to the milling question. Sorry for the thread Hi Jack.

I'd think an appropriate use for blue stain Pine from the home lumber end would be to make a rustic looking beam out of something else. You know what I'm talking about. A high ceiling home has steel or nailed together 2 x 10's for a beam.


I've never really noticed that (and I looked at hundreds of ponderosa pine under attack by mountain pine beetle in my old research). What kills the brood is very cold winters (days in the single digits or less) in lodgepole pine forests (thinner bark).

My work showed that thinning dense second-growth ponderosa pine greatly reduces beetle kill in an outbreak situation immediately, in the same season, because of the increase in tree spacing. Apparently, the beetles' pheromone communication system doesn't work as well in thinned stands, and they can't aggregate on individual trees efficiently in high enough numbers to kill them.

The competing theory---that thinning increases tree vigor, and therefore resistance to beetle attack---only comes into play if beetles land on a particular tree. One way to look at vigor is recent growth increment; the slower the growth, the lower vigor and lower resistance. In my thinning teatments, of those trees that were attacked in unthinned or thinned plots, slow growing trees tended to die more often---but almost no trees were killed in thinned plots compared to unthinned (the ratio was around 1: 20).

So, its a good idea to thin your forest for lots of reasons, including increased growth, reduced fire danger, and reduced beetle kill. Although fire danger actually goes up for a few years, untill the slash decays, and some bark beetles (Ips beetles) can build up in green slash and kill trees.

"If its not one thing, it's another"

--Roseanne Rosanadana
 
Have a few hundred BF of blue stain sugar pine in the board pile. Beautiful stuff. I plan to trim my kitchen, and part of the house with it. Was a dead standing tree (30" dbh) behind my shop.
Sad to say that I killed it. Spurred up it to set some rigging a few years before it died. I knew better. Did years of FS climbing (cone collection, scion,etc.)- spuring most pines is a no-no!
Russell
 
I can only offer my own experience on sawing some logs that were from standing dead pines (white and red), each at least 24" base. The logs had some of that greenish tinge showing, coming from the outside towards the heartwood. The sawyer that I had come in with his porta-band mill was not optimistic on the quality of the lumber they would net, but I had a "let's give it a try" attitide so we sawed into them. I had him cut all the red pine into 2x6, which were on par with any commercial SPF 2x6 for strength qualities. The greenish staining and any small borer holes did not impact the sticks. The white pine logs were sawed into 1" boards, and although they showed similar stainign and some borer holes, the strength was on par with any other white pine I've seen (which is not to say all that strong in general). As was stated in a previous post, the best way to tell is by felling the tree and plunging your saw into the log. You'll know right away by the sawdust produced and butt end appearance. My overall advice is don't be afraid to try sawing a particular log just because of beetle holes or some staining. The worst you'll wind up with is more firewood pieces.
 
I just returned from our CO. ranch were I cut up about 1500bf of ponderosa beetle kill. It is definatly pretty stuff, very soft though. I have it stickered there in the garage and Im praying that I avoided any sticker stain, since this is my first milling experiance.
Now I am dreaming up plans worthy of the booked peices I have such as this one.
beatlekill-1.jpg
 
The MPB is the vector of the blue stain fungus that causes some really cool coloration of the wood. It really doesnt effect the density of the wood. There is a saw mill in Kremmling that specializes in milling beetle kill for siding and I heard there is one in Keystone now. I deal with a mill in Woodland Park that mills beetle kill you may want to call them if you have any questions. We dont mill any of the beetle kill we remove, but we are starting up a program milling all our Maple, Ash, Oak, and other hard woods. If you have any questions drop me a PM
 
blue stain 2x4

judson as far as i can tell the blue stain has no issues with the integrity of the wood. in a 2x4 that is what we plane day after day and i've have stated to see some great possibilities in making projects out of it. i see some of it that looks like blue sky with clouds in it, so i have started pulling some and i want to make like coffee&end tables out of it
 
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