The Body Language of Trees
- Thread starter zevr
- Start date
- Location
- under grace
WOW!! i thought the bok was awesome and im not sure all of that work could be invalid.? maybe some of the ratios and the like ., but using the visual tree assesment has helped me to "read" a tree in more detail.I look more closely at all of the trees issues than prior to reading the book!
I would like more recent info as well!! good post!
I would like more recent info as well!! good post!
guymayor
Branched out member
- Location
- East US, Earth
It's an excellent5 book--just reread it and got reminded of that in a big way.
The Axiom of Uniform Stress has been battered about a bit, and some of the data on the relationship of shell walls and failure rates was lacking, so some formulas do not work well.
But we should know to doublecheck that kind of stuff anyway, right?
The Axiom of Uniform Stress has been battered about a bit, and some of the data on the relationship of shell walls and failure rates was lacking, so some formulas do not work well.
But we should know to doublecheck that kind of stuff anyway, right?
- Location
- under grace
agreed Guy!! it seems to me in the natural world the rules tend not to be hard and fast! I may be assuming here but i think part of what a lot of us like about this work is its diverse nature . the fact that it is science.... but maybe like art rooted in science?? does that make sense? or does it sound too new age?
- Location
- Charlotte, NC.
The only one I've read is "Tree Mechanics". If you haven't read it I highly recommend it.
Art imitates nature, how we view nature changes with scientific advancements.
Art imitates nature, how we view nature changes with scientific advancements.
guymayor
Branched out member
- Location
- East US, Earth
[ QUOTE ]
...i think part of what a lot of us like about this work is its diverse nature . the fact that it is science.... but maybe like art rooted in science?? does that make sense? or does it sound too new age?
[/ QUOTE ]Just new age enough for me--what I like about it is the focus on tree structure and its positive adaptations. Modern looks at risk seem to leave that part out, or treat it as an insignificant and occasional response to a defect instead of a constant and powerful response to movement.
TRA seems skewed to the negative, whereas I read Mattheck as aware of the positive first. What holds the tree up comes first, because it came first. Or is that just too simple, or old-age logical, to follow?
...i think part of what a lot of us like about this work is its diverse nature . the fact that it is science.... but maybe like art rooted in science?? does that make sense? or does it sound too new age?
[/ QUOTE ]Just new age enough for me--what I like about it is the focus on tree structure and its positive adaptations. Modern looks at risk seem to leave that part out, or treat it as an insignificant and occasional response to a defect instead of a constant and powerful response to movement.
TRA seems skewed to the negative, whereas I read Mattheck as aware of the positive first. What holds the tree up comes first, because it came first. Or is that just too simple, or old-age logical, to follow?
- Location
- under grace
Ha ha ha !! no !! i like it and agree! old age.....im headin there ,but with a good fight!
Thanks!
In the ISA TRACE course manual, I found an interesting (though un-cited) idea in the section on failures in the crown. This is slightly reworded:
A dense canopy acts as a sail at high wind-speeds - it can be moved laterally by wind, BUT it also provides dampening resistance as it returns to center.
When wind force exceeds branch strength, branches break: the canopy becomes more porous.
When the canopy becomes porous the whole tree does not fail immediately, but it looses its dampening ability. It can now move rapidly, which transmits rapid shocks to the roots and can lead to breakage.
This description made me reconsider preventative thinning and reduction pruning. It seems that this is akin to thinning without reduction (loosing sail without reducing leverage). I also visualize this occurring after reduction pruning, but before the inner canopy pushes leaf surface.
What implications do you think this statement has on pruning?
In the ISA TRACE course manual, I found an interesting (though un-cited) idea in the section on failures in the crown. This is slightly reworded:
A dense canopy acts as a sail at high wind-speeds - it can be moved laterally by wind, BUT it also provides dampening resistance as it returns to center.
When wind force exceeds branch strength, branches break: the canopy becomes more porous.
When the canopy becomes porous the whole tree does not fail immediately, but it looses its dampening ability. It can now move rapidly, which transmits rapid shocks to the roots and can lead to breakage.
This description made me reconsider preventative thinning and reduction pruning. It seems that this is akin to thinning without reduction (loosing sail without reducing leverage). I also visualize this occurring after reduction pruning, but before the inner canopy pushes leaf surface.
What implications do you think this statement has on pruning?
[ QUOTE ]
I've been told that some of Mattheck's ideas have been invalidated or modified since the first publishing. Can anybody share some insight?
[/ QUOTE ]
I wrote this back in 2000 or so, and I'm now gathering additional posts and writings, including a lecture request to the ISA..
---------------------------
<Bob Wulkowicz>
Posted Monday April 10, 2000 02:50 AM
I wrote this in the Arb. Lit. forum and decided to move it here as an Arg. Lit. item to stir up some juices:
----------------------
I have a lot of problems with Mattheck's works. It has been my plan to write very specific challenges to the concepts and assumptions he has offered. For now, I'll keep it simple.
Trained, traditional engineers--or physicists--are most comfortable in the world of phenomena reduced to equations, and much is to be said in support of that inclination. For me however, Mattheck tugs and pulls the issues of trees over into this often tidy world whether or not the issues fit.
For example, in the finite element method of computer analysis he provides, the hidden truth is that the analysis works on monolithic materials, steel, etc., with the stresses, failures, and propagation's of problems operating in a single type of material consistent through its mass. The photos of FEM are persuasive in that they are windows of the "new science," but they are also deceptive if they're done about apples when we're talking about oranges.
Klaus shows the corresponding stress and patterns of stress in making a hole in a homogeneous material which is to remove an amount of an area that should be available to share the loads. The patterns of stress concentration are understandable and, yes, he is teaching us valid and useful information. Engineers build that information into their designs to make better and more successful outcomes. Liberty ships were lost because of crack propagation that continued unchecked until the ship split in half and sank. The awareness of that probability lead to anticipation and reinforcement with future designs.
Mattheck takes this one attribute of monolithic materials and expands it to trees. Holes in trees are "flaws" and we can suddenly infer the structural liabilities of trees from a touch of sophomoric text on engineering equations. In same-stuff materials, there are engineering solutions--reinforcement, drilling holes in the end of a crack to spread the load, and in the last hundred years, composites and laminations. Oddly, trees thought up laminations more than a hundred million years ago.
Indeed, trees are the quintessential proponents of living composite lamination. Klaus's sense of flawed structure is quite distant from them. Mattheck, to me, stops abruptly when what he theorizes resembles an equation. See, he says, it fits--so, let's get on to the next question... I'm sorry. I have a difficult time with that especially when it's presented as dogma to an information-starved audience like those of us in the arboriculture business.
The approximation of plate steel with a hole under tension (the plate pulled at each end) has very little to do with a tree. At best, it is illustrative of a "plate steel with a hole under tension" in Engineering 101. Mattheck would have us stop at comfortable linear equations, when trees are unquestionably non-linear.
His FEM offerings also assume that growth in a tree is akin to the thermal expansion of a homogeneous material. Well, it's a shame that trees haven't read his works; they grow completely differently and the differences are so substantial that he is only giving us a great deal of simplistic misinformation instead of what we need.
I cannot, in good conscience, evaluate a tree based on his pronouncements. People would be shocked if they found out the thinness of the base from which his hollow tree failure "guidelines" are built. But in a world where we'll cut down a tree at the hint of a shadow of a lawyer, what difference does it make?
Maybe I'll present it as a paper in detail at the ISA August conference.
Bob Wulkowicz
--------------------------------------------------------
Posted Monday April 10, 2000 09:10 PM Scott Cullen
Reply to post by Bob Wulkowicz, on April 09, 2000 at 12:50:02:
Bob,
I think there are two (at least) key issues surrounding the "culture" of all this.
The first I understand pretty well. It's a phenomenon that many of us have observed and that you describe quite well: "...an information-starved audience like those of us in the arboriculture business." Whether it's from an honest and responsible desire to base arboriculture on "science" or a more self serving desire to have a good sales pitch or an awestruck self esteem thing there's this pattern of grasping for and locking onto nuggets of theory or "fact" and making icons out of the theorizers. There are lots of groupies. "If so and so says it who are we to question?"
The second I'm just starting to get a handle on. We've seen it for a long time in the industry sponsored research on pesticides... "of course this chemical is good." There are commercial products coming to market which are by-passing industry third parties and are the business enterprises of the theorists themselves. Layer onto this researchers wandering along the edges of their fields and along the edges of charted territory and you add some more lack of certainty. And finally add in rivalries among theorists which propell them into attacks and defenses against each other rather than refined attacks on the unknown.
Combine those potential biases with a grasping and non-scientific audience and what do you get? I guess you get overstatements of certainty.
What should we be getting? Maybe a little better understanding, sharper questions, another step along the way. More tools to apply differently to differing fact patterns rather than allegedly universal rules. The fault is as much among the receivers as the providers.
OK moving back to your specific observations...
I think you're not alone in questioning. There's another German scientist named Lothar Wessoly who is all over Mattheck. As nearly as I can tell the science of Mechanics is divided into Statics, Dynamics and Strength of Materials... Mattheck is a Strength of Materials guy and Wessoly is a Statics guy. Kim Coder is setting up a May, 2001 conference on tree mechanics and I think clarification of these differences may be on the agenda.
A number of the Ph.D. types (no names to protect the innocent) are reserved in their application of Mattheck data and "rules" but not necessarily rejecting of it all.
Next... Assuming Mattheck is a Strength of Materials guy one would suspect he has or should have made some consideration of the differences between steel and organic materials. In fact some of his work involves computer modeling of the similarities among trees, animal and human bone, bird's beaks and so forth. Can he have ignored that the material propertis are different from a steel lifting hook? Dunno.
Have you looked at Mattheck's "windthrow" materials and do you have any comment about them?
Scott (Cullen)
------------------------------------------------------
I've been told that some of Mattheck's ideas have been invalidated or modified since the first publishing. Can anybody share some insight?
[/ QUOTE ]
I wrote this back in 2000 or so, and I'm now gathering additional posts and writings, including a lecture request to the ISA..
---------------------------
<Bob Wulkowicz>
Posted Monday April 10, 2000 02:50 AM
I wrote this in the Arb. Lit. forum and decided to move it here as an Arg. Lit. item to stir up some juices:
----------------------
I have a lot of problems with Mattheck's works. It has been my plan to write very specific challenges to the concepts and assumptions he has offered. For now, I'll keep it simple.
Trained, traditional engineers--or physicists--are most comfortable in the world of phenomena reduced to equations, and much is to be said in support of that inclination. For me however, Mattheck tugs and pulls the issues of trees over into this often tidy world whether or not the issues fit.
For example, in the finite element method of computer analysis he provides, the hidden truth is that the analysis works on monolithic materials, steel, etc., with the stresses, failures, and propagation's of problems operating in a single type of material consistent through its mass. The photos of FEM are persuasive in that they are windows of the "new science," but they are also deceptive if they're done about apples when we're talking about oranges.
Klaus shows the corresponding stress and patterns of stress in making a hole in a homogeneous material which is to remove an amount of an area that should be available to share the loads. The patterns of stress concentration are understandable and, yes, he is teaching us valid and useful information. Engineers build that information into their designs to make better and more successful outcomes. Liberty ships were lost because of crack propagation that continued unchecked until the ship split in half and sank. The awareness of that probability lead to anticipation and reinforcement with future designs.
Mattheck takes this one attribute of monolithic materials and expands it to trees. Holes in trees are "flaws" and we can suddenly infer the structural liabilities of trees from a touch of sophomoric text on engineering equations. In same-stuff materials, there are engineering solutions--reinforcement, drilling holes in the end of a crack to spread the load, and in the last hundred years, composites and laminations. Oddly, trees thought up laminations more than a hundred million years ago.
Indeed, trees are the quintessential proponents of living composite lamination. Klaus's sense of flawed structure is quite distant from them. Mattheck, to me, stops abruptly when what he theorizes resembles an equation. See, he says, it fits--so, let's get on to the next question... I'm sorry. I have a difficult time with that especially when it's presented as dogma to an information-starved audience like those of us in the arboriculture business.
The approximation of plate steel with a hole under tension (the plate pulled at each end) has very little to do with a tree. At best, it is illustrative of a "plate steel with a hole under tension" in Engineering 101. Mattheck would have us stop at comfortable linear equations, when trees are unquestionably non-linear.
His FEM offerings also assume that growth in a tree is akin to the thermal expansion of a homogeneous material. Well, it's a shame that trees haven't read his works; they grow completely differently and the differences are so substantial that he is only giving us a great deal of simplistic misinformation instead of what we need.
I cannot, in good conscience, evaluate a tree based on his pronouncements. People would be shocked if they found out the thinness of the base from which his hollow tree failure "guidelines" are built. But in a world where we'll cut down a tree at the hint of a shadow of a lawyer, what difference does it make?
Maybe I'll present it as a paper in detail at the ISA August conference.
Bob Wulkowicz
--------------------------------------------------------
Posted Monday April 10, 2000 09:10 PM Scott Cullen
Reply to post by Bob Wulkowicz, on April 09, 2000 at 12:50:02:
Bob,
I think there are two (at least) key issues surrounding the "culture" of all this.
The first I understand pretty well. It's a phenomenon that many of us have observed and that you describe quite well: "...an information-starved audience like those of us in the arboriculture business." Whether it's from an honest and responsible desire to base arboriculture on "science" or a more self serving desire to have a good sales pitch or an awestruck self esteem thing there's this pattern of grasping for and locking onto nuggets of theory or "fact" and making icons out of the theorizers. There are lots of groupies. "If so and so says it who are we to question?"
The second I'm just starting to get a handle on. We've seen it for a long time in the industry sponsored research on pesticides... "of course this chemical is good." There are commercial products coming to market which are by-passing industry third parties and are the business enterprises of the theorists themselves. Layer onto this researchers wandering along the edges of their fields and along the edges of charted territory and you add some more lack of certainty. And finally add in rivalries among theorists which propell them into attacks and defenses against each other rather than refined attacks on the unknown.
Combine those potential biases with a grasping and non-scientific audience and what do you get? I guess you get overstatements of certainty.
What should we be getting? Maybe a little better understanding, sharper questions, another step along the way. More tools to apply differently to differing fact patterns rather than allegedly universal rules. The fault is as much among the receivers as the providers.
OK moving back to your specific observations...
I think you're not alone in questioning. There's another German scientist named Lothar Wessoly who is all over Mattheck. As nearly as I can tell the science of Mechanics is divided into Statics, Dynamics and Strength of Materials... Mattheck is a Strength of Materials guy and Wessoly is a Statics guy. Kim Coder is setting up a May, 2001 conference on tree mechanics and I think clarification of these differences may be on the agenda.
A number of the Ph.D. types (no names to protect the innocent) are reserved in their application of Mattheck data and "rules" but not necessarily rejecting of it all.
Next... Assuming Mattheck is a Strength of Materials guy one would suspect he has or should have made some consideration of the differences between steel and organic materials. In fact some of his work involves computer modeling of the similarities among trees, animal and human bone, bird's beaks and so forth. Can he have ignored that the material propertis are different from a steel lifting hook? Dunno.
Have you looked at Mattheck's "windthrow" materials and do you have any comment about them?
Scott (Cullen)
------------------------------------------------------
KTSmith
Branched out member
- Location
- Maine, New Hampshire
Zevr's post touches on Ken James' work on the value of the sway of small-diameter branches to dampen the harmonic oscillation of larger branches and stems during dynamic loading (such as with gusts of wind). He has published a lot, you could start with:
http://www.treelink.org/joa/2003/may/06James.pdf
http://www.treelink.org/joa/2003/may/06James.pdf
treevet
Branched out member
- Location
- Cincinnati, Ohio
Incredible thread and posts. I brought up the subject of Zevr's post to TRACE instructor BCMA Terry Flanagan a couple of weeks ago and he was a bit caught by surprise and unaware. So much of this subject has researchers scurrying around as we type I bet. Very interesting times.
Wulky's stuff, as usual.... very thought provoking. I just read Ansi A300 part 9 (2011) (Tree Risk/Structure Assessment) last night and was searching for this very kind of thread for those as interested as I am in this topic.
At the seminar the entity of Tree Failure Data Base was invoked in discussion but not elaborated on. Wonder just how much input (shell wall thickness thresholds, species specific reaction wood/ woundwood competence, lean, species specific pathogens, etc. etc.) that findings of this data base has on where we are headed in....
....the evolution of the standard on quantifying the risk of trees that is currently in vogue....and at the end of the day, the report generated to protect targets (or at least give fore warning) from catastrophic events with our new knowledge/system. Seems to me it is way underused as mentioned above, while some look to carve their names in stone in history.
Hard to fathom but as I brought this subject up on another forum many of the resident meat heads were dramatically offended that someone other than them with the knowledge of the ages as td artiste s (read (cough while saying) "bbbulllschit"), and are armed and ready to fight any suggestion that they attend a seminar or crack a book or that anyone could be allowed to trump their unsystematic and unscientific opinion. lol.
Wulky's stuff, as usual.... very thought provoking. I just read Ansi A300 part 9 (2011) (Tree Risk/Structure Assessment) last night and was searching for this very kind of thread for those as interested as I am in this topic.
At the seminar the entity of Tree Failure Data Base was invoked in discussion but not elaborated on. Wonder just how much input (shell wall thickness thresholds, species specific reaction wood/ woundwood competence, lean, species specific pathogens, etc. etc.) that findings of this data base has on where we are headed in....
....the evolution of the standard on quantifying the risk of trees that is currently in vogue....and at the end of the day, the report generated to protect targets (or at least give fore warning) from catastrophic events with our new knowledge/system. Seems to me it is way underused as mentioned above, while some look to carve their names in stone in history.
Hard to fathom but as I brought this subject up on another forum many of the resident meat heads were dramatically offended that someone other than them with the knowledge of the ages as td artiste s (read (cough while saying) "bbbulllschit"), and are armed and ready to fight any suggestion that they attend a seminar or crack a book or that anyone could be allowed to trump their unsystematic and unscientific opinion. lol.
guymayor
Branched out member
- Location
- East US, Earth
[ QUOTE ]
When the canopy becomes porous the whole tree does not fail immediately, but it looses its dampening ability. It can now move rapidly, which transmits rapid shocks to the roots and can lead to breakage.
[/ QUOTE ]
Perhaps, to some degree. This concern can be handled with proper dose and location and timing of thinning cuts.
"This description made me reconsider preventative thinning and reduction pruning. It seems that this is akin to thinning without reduction (loosing sail without reducing leverage). I also visualize this occurring after reduction pruning, but before the inner canopy pushes leaf surface."
Reduction cuts on outer foliage as I understand it do not affect damping, so it's not clear what is being visualized.
When the canopy becomes porous the whole tree does not fail immediately, but it looses its dampening ability. It can now move rapidly, which transmits rapid shocks to the roots and can lead to breakage.
[/ QUOTE ]
Perhaps, to some degree. This concern can be handled with proper dose and location and timing of thinning cuts.
"This description made me reconsider preventative thinning and reduction pruning. It seems that this is akin to thinning without reduction (loosing sail without reducing leverage). I also visualize this occurring after reduction pruning, but before the inner canopy pushes leaf surface."
Reduction cuts on outer foliage as I understand it do not affect damping, so it's not clear what is being visualized.
treevet
Branched out member
- Location
- Cincinnati, Ohio
As I understand the premise, since this is a discussion relative to risk and perceived hazards what is being considered is a tree under extreme force of high winds and/or unusual winds.
The lever arm is being torqued to the verge of failure at the bending moment (at or beyond the point of permanent deformation....strain). The interior crown reduced tree and the unpruned tree are at the same impass at this point but.....if no failure occurs then
The tree with the interior pruning now will not have a sail to dampen the return (recoil)stressing the roots in tension and compression and torsion....again and again setting up a potential shear plane or uprooting, or limb failures, etc.. Throw in some defects and the probability of catastrophic failure increases in situations that are being sought to be protected.
As for day to day challenges of wind, reaction wood suffices to bolster stems for prevailing winds if they are constant in an area. In this situation (never any extreme weather events) interior crown reduction may be prescribed for physiological improvement or just aesthetics.
So if what we are striving for is the perfect tree then it may NOT be the tree we have prescribed interior crown reduction for if exposure to high winds is the risk reduction/mitigation we are seeking.
The lever arm is being torqued to the verge of failure at the bending moment (at or beyond the point of permanent deformation....strain). The interior crown reduced tree and the unpruned tree are at the same impass at this point but.....if no failure occurs then
The tree with the interior pruning now will not have a sail to dampen the return (recoil)stressing the roots in tension and compression and torsion....again and again setting up a potential shear plane or uprooting, or limb failures, etc.. Throw in some defects and the probability of catastrophic failure increases in situations that are being sought to be protected.
As for day to day challenges of wind, reaction wood suffices to bolster stems for prevailing winds if they are constant in an area. In this situation (never any extreme weather events) interior crown reduction may be prescribed for physiological improvement or just aesthetics.
So if what we are striving for is the perfect tree then it may NOT be the tree we have prescribed interior crown reduction for if exposure to high winds is the risk reduction/mitigation we are seeking.
New threads New posts
-
test
-
-
-
Fruit tree holding on by a thread, client wants to get another year out of it. Thoughts?- Started by climbingmonkey24
- Replies: 49
-
-
-
