Reaction Wood

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I'll get some pics on Monday. I know of a 90'~ish foot White Pine at one of our clients properties I'll be at that has a very good example of reaction wood. The tree grows at about a 5-10* lean, with about a 28-30" trunk, the bottom 10 feet of the trunk on the underside of the lean is ripple after ripple, looks like an accordion. Pretty cool.
 
Yes, this is what he said. Where did he say "stop thinking"?

Treevet, your ability to become offensive passes all bounds.

Sylvia

You are very offensive yourself lady.

I too looked forward to a discussion about reaction wood. The thread titled "Reaction wood" might suggest a definition of reaction wood. I give opinion on a definition. Your husband replies with a longwinded DEFINITION of "fasciation" copied from a text. Duhhhh.

Next you scold me for GIVING DEFINITIONS and, in true form as a woman, bring up something from a year ago (again where you challenged me giving a definition.....not a wrong definition mind you, just a definition......for relevant words in a thread where you, in your usual self important fashion, prefer to make your own definitions).

"Any wood that forms in response to some external or internal forces produces a reaction. This could then be termed "reaction wood" Sylvia MC

REALLY?? Then ALL wood that has formed any time any place in the history of wood is reaction wood.

You need to get your head out of where the sun doesn't shine and quit pushing your husband into making silly posts.
 
Very cool!

I saw a lot of that in the trees along the coast in N. California. I had some pics but can't seem to find them at the moment.

Like the corkscrew redwood for example?

I'm not certain that twisted looking trunks are reaction wood in many cases. Here's part of the corkscrew redwood, and another along Prairie Creek trail.

It is easy to get into a "black and white" mind set.

ANY wood that forms in response to some external or internal force produces a "reaction". This could then be termed "reaction wood". Trees are reactionary organisms; hence, all the "tropisms". They constantly react to their environment.

In the loose sense of "reactionary" we could even include the tree itself as part of its environment. Where virtually all wood of every tree would be reactionary.



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Is it possible that those big long low horizontal spreading branches are acting like a sail, causing a twist in the trunk, whereas the other tree's branches are going straight up, exerting less twisting effect...

Excellent observation. Surely producing exceptional torque in relation....it stands to reason.
 
tension wood forms under a limb, compression wood forms on the topside of a limb, reaction wood forms as a result of growing conditions, ie: growing on a slope, prevailing winds,"a reaction to the conditions"
 
Mario, nice ridge on that first pic! That's what I'm talking about.

Watch for the 2nd draft of the ANSI Risk standard to come out for review on the TCIA site soon. It will have what may become the "official" definition of reaction wood. Something about wood formed in response to mechanical stress. Woundwood is not in there, at present.

Ripples on the underside of the lean of a pine would be interesting to see. I've seen em on the tension side of a beech. I can't rule out mutation but it's far from obvious to me. Not related to buds that I can see.

I agree with Sinclair on fasciation. It's always useful to draw from authoritative (and i don't use that word lightly) sources. Narrowing definitions makes paradigms too rigid, boxing in thought.
 
Mutations excluded then wood formed by twisting could be referred to "torsion" wood. Wood formed by combinations of these may need another term such as that formed in "Bottle butt" (what I was leading into prior to attempts at being censored by the MC's) and even large buttresses. A huge buttress certainly is growing in reaction to stresses as it does not grow even nearly a consistent fashion with the rest of the trunk in mass.
 
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Fascinating pictures.

I have to take a drive up into the foothills and post a picture of a great "distorted" Corymbia maculata. I used to have a few of my own photo's we took years ago but they are the victims of data loss:cry: "Twisted" or "braided" trunks are fairly common in C.maculata here in Perth (about 3500km's from Derwoodii) but seem to be far less common in C.citriodora.

My concern with Bermies suggestion of torque reaction alone as a cause is that the effect is visible in some trees of a given species but not others located nearby and of similar age. Perhaps it is a combination of external forces AND a genetic predisposition toward this growth pattern. I would be interested to note if the growth direction was aligned the with coriolis effect of a given hemisphere or whether there were both clockwise and anti clockwise "braiding" in the same location. I would also be very keen to see the results of any testing that could be done to indicate fluid flow from root to canopy and whether it follows the "braiding" precisely. Exactly how this could be tested would be a challenge!
 
Just took the time to google and read the Cassian Humphreys article TS & Derwoodii were referring to. Well worth the effort. I found it googling this phrase "Self Optimisation of Gum trees – Braided Reaction Wood Development". It is hosted at a website that this forum does not link to.
 
The claim: The coriolis effect influences which direction water spirals down drains in different hemispheres.

The truth: False

Whichever direction the flow comes from, it continues in that same direction no matter what hemisphere you are in. But, with that said, what about the numbers? Seems like i read somewhere that well over 90% of trunk spirals are counterclockwise in the Northern hemisphere. Hurricanes in the northern hemisphere are counterclockwise and, apparently, the majority of tornadoes too.

If a tree is predisposed through genetics and prevailing forces exacerbate then perhaps the coriolis effect of the earth's rotation has a dog in this hunt?

Very interesting topic.
 
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Just took the time to google and read the Cassian Humphreys article TS & Derwoodii were referring to. Well worth the effort. I found it googling this phrase "Self Optimisation of Gum trees – Braided Reaction Wood Development". It is hosted at a website that this forum does not link to.

Found the document and skimmed through for some hightlights.

At the end, he wrote:

demonstrating
to arborists that we need to be open to other possibilities in relation to trees as self
optimisers

One thing worth introducing alongside, is that arborists may also want to keep in mind the possibility of trees being self-terminating, too. Or to put it another way, genetically designed to live for approximate intervals or die within approximate time intervals. Take for example species prone to weak unions, susceptible to insects, or short-lived.

The entire natural collection of tree species seems to be a combination of optimization blended with limitations for termination. If annuals have the limitation of a year, certainly trees can have limitations of decades or an approximate number of centuries.

Take Grand fir - isn't 3 centuries about the limit for any of those?

The .pdf had a fairly good assortment of pics. One caught my attention where he commented about a strip, and it looks like a typical crack on bark from normal grow. Maybe he was not pointing to just the small crack.

:)
 
I think it is good that we can review our preconceptions about tree biology, and plant physiology in general, it is one of Cassian's admirable traits that he is willing to state what he is thinking about a topic whislt he is still in the process of working through all the possible angles and exp[lainations for his observations.

I helped proof read the article and along with some better known Arboreal names have been pondering aspects of the phenomenom Cass calls Braided Reaction Wood...so I would like to add some of my partially formed ideas....

No microscopic analysis has been done of the wood cells through these dramatic sections of branch, limb and stem...so it really is not possible to say with certainty that the cells have or do not have the anotomical changes associated with 'reaction wood' in its generally understood definition.

We don't know if these braided forms are stronger weaker or exhibit no significant difference in strength under loading (in all its manifestations!).

Both these unknowns are things Cass hoped to be able to gain funding to explore.

Personally I do not believe that these braided forms nor many of the other pics of dramatic body language posted by others in this thread are fasciation, at least not in my understanding of the term.

I think Dave (TV) might well be right that we will need some other term to describe what we are observing...or perhaps the cells will give up their secrets under the microscope.

There is a term which I have seen used to describe the growth responses in plants to temperature, wind and even touch (with other plants and/or animals) and that is of course Thigmomorphogenesis (I have to admit to liking its sound more than the convincing weight of the arguement) some of the contorted twisted growth patterns we observe certainly seem (to me at least) to defy explainations of tortional wind loading...especially when those trees are the same age and stature as their very "straight" close neighbours.

I have observed trees with very unusual growth responses that seem to be explained by the protracted contest over territory within wood tissues between wood decay fungi and host, bacterial infection and host, even parasitic plant and host.

It is interesting that this braiding has been observed in quite a number of different genus, in both the northern and southern hemispheres. Certainly for me the most dramatic and obvious examples are in our spotted gums Corymbia citriodora/henryii/maculata but I have also personally seen remarkable 'muscle like' forms in Caesalpiniaceae, Sapindaceae, and (of course) Platanaceae.

Since some of you might not be able to find the article here are a couple of scaled down pics of the braided phenomenon.

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The claim: The coriolis effect influences which direction water spirals down drains in different hemispheres.

The truth: False

Whichever direction the flow comes from, it continues in that same direction no matter what hemisphere you are in. But, with that said, what about the numbers? Seems like i read somewhere that well over 90% of trunk spirals are counterclockwise in the Northern hemisphere. Hurricanes in the northern hemisphere are counterclockwise and, apparently, the majority of tornadoes too.

If a tree is predisposed through genetics and prevailing forces exacerbate then perhaps the coriolis effect of the earth's rotation has a dog in this hunt?

Very interesting topic.


Lol. I wondered if someone would discuss the water-down-the-drain phenomenom!

My question was in fact more along the lines of the effect the earths rotation has upon wind direction in hurricanes/cyclones in the respective hemispheres. In fairness it was a bourbon generated idea but it would be pretty cool if in fact there was a corellation between the apparent direction of "twist" and the hemisphere in which the sample was located.

"Thigmomorphogenesis". Fair dinkum Sean I reckon you lie awake at night thinking up words that most normal people would need to dislocate their jaw to pronounce. :bowdown:

Just an aside but I noticed that Cassian often refers to C.citriodora as a Spotted Gum and nowhere in the article does he mention C.maculata. I know these 2 are genetically close so is he referring to a hybrid? For my money the 3 pictures you showed were run-of-the-mill C.maculata.

Mario I don't believe genetic mutations are designed. Taking aside the contentious issue of creation vs evolution, most short lived plants are prolific seed producers with rapid growth. For a mutation to be succesful (and by default this braiding appears to be succesful at very least amongst C.maculata) it would need to give the plant a reproductive advantage. That is, if this type of growth reduces the longevity of the plant then it would quickly die out unless it produced a greater number of viable seeds than average.

Of course we meddling humans really stuff things up by artificially spreading samples across the globe so this form may actually be a dud but we keep planting its seeds so it keeps popping up!
 
"Thigmomorphogenesis". Fair dinkum Sean I reckon you lie awake at night thinking up words that most normal people would need to dislocate their jaw to pronounce

Ha ha I wish I could claim to have thought up that bizarre term...

Just an aside but I noticed that Cassian often refers to C.citriodora as a Spotted Gum and nowhere in the article does he mention C.maculata. I know these 2 are genetically close so is he referring to a hybrid

Common names are a real pain, spotted gum is just one that C.citriodora has, lemon scented gum being another.

The plot becomes even less clear once we look at what the botanist have been doing with the series Maculatae (spotted gums) current think ing as far as I understand it is that the taxa are now seperated into;
Corymbia citriodora subsp.citriodora (Lemon scented gum found in northeastern Queensland )
Corymbia citriodora subsp variegata (Spotted gum found in southeastern Queensland ...but goes as far south as Grafton) This was formally named Corymbia maculata.
Corymbia Henryi (Large leaved spotted gum found in southeastern Queensland and northern NSW)

BTW I am not suggesting that any of this taxonomic gymnastics makes any sense to me at all:deadhorse:

As for Mario's interesting point about self optomising as compared to self terminating...well I often find concepts of programmed death of the organism hard to fit with the evidence of regenerative genetics in most plants, there was a very good article written some years back by Peter Del Tredici "Aging and Rejuvenation in Trees" well worth a read, attached below.

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The most obvious regenerative aspect that is common to trees and small plants is seed production.

Even annuals produce seeds.

But that would not really be a "self" optimization.

Alder's don't seem to fit the mold very well for long term self-optimization. They will reiterate if broken, for example, but are pretty much "sacrificial" trees.

If they had a will, we could almost stretch the vocabulary to say self-sacrificial. But they remain genetic. Anyhow, Alders are well adapted to repair areas of nature. More like nature's self-optimization with the tree helping to fix nitrogen or nutrition in areas. Alders don't really last long at all. Very short lived. And for where they grow, the short life span is very practical environmentally.
 
As for Mario's interesting point about self optomising as compared to self terminating...well I often find concepts of programmed death of the organism hard to fit with the evidence of regenerative genetics in most plants, there was a very good article written some years back by Peter Del Tredici "Aging and Rejuvenation in Trees" well worth a read, attached below.

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Mario's example of alders speaks of a short-lived plant by genetics, but like Sean I would point to rejuvenation as an almost universal tendency, with the right conditions and care.

Here's a coincidence, aka do you believe in magic--That piece that you attached is the same that is quoted at the end of the pruning article (my present version is 1.9 mb too big for here) in Arborist News this month, so you should be seeing it any week now. :mad: . The man has great plant skills and remarkable insight into their behavior. His recent book on urban ecology is outstanding.
 
Just took this pic today.

No real stress on the root wood. Shows that trees can simply grow tissue spiraled this way.

A redwood tree root.

About 16" diameter at the widest point. This is about 15' worth of surface root in the image. The trunk was about 20 feet to the right of the image.

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