Limbs with included bark do not need to be cut off

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We got the idea because tight crotches with included bark sometimes fail catastrophically.:rolleyes: Granted -most of them don't fail- but they are more likely to fail nastily than other unions. Perhaps the trees don't care and merrily grow on their way but human beans hate limbs in their driveways and sudden holes in the canopy of their trees(or worse a third of the tree lying across the hood of their car). I wish Bob would discuss these things in a more reader friendly way instead of being the perpetual protagonist.-or is he just an antagonist?:confused:

Browsing the O.T. forum I saw what prompted Spydy's post. Bob's original post addresses the fallacy of thinking that tight crotches/upright branches are a weak arrangement.-Understood-but since the physics dictate that upright limbs are less stressed/bearing less of a torque load they seem to be more susceptible to failure when an unusual load is placed on them. If you think about it though more horizontal brances break under snow loads and freak winds. The included bark is really another subject (Bob did list them seperately) It is the "monkey wrench" in the upright branch equation. The Upright branch with INCLUDED BARK is the one that may break in an attention getting fashion. Peace Bob-lets keep the discussion going.:angel:
 
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Gilman did some studies that showed a more important indicator of branch union strength is the size ratio. This is a case where science has confirmed what casual observation has shown. The closer the ratio comes to the magic 1:3 the stronger the union. Attachment angle is less an issue also.

The article was published in the ISA Journal of Arboriculture.

Tom
 
So, we nip the inclusion and allow the branch bark to join up with the primary stem's tissue? Why plexiglass- just the better to see you with my dear?
 
Originally posted by Stumper
So, we nip the inclusion and allow the branch bark to join up with the primary stem's tissue? Why plexiglass- just the better to see you with my dear?


It may be impossible to have you guys see anyting without your saws. Loosen up.

My goals as a steward, besides re-arranging the cambial sheet so that the included bark potential disappears on the day we do the work, include minimal intrusion; mininal damage; minimal exposure to pathogens.

If one thinks in chainsaws, these are strange, distant goals. Most likely, you'll fight all the way.

Squint a bit, so you can see a larger picture, because details of old ideas interfere with the new and upcoming, better to see you, my dears...


Bob Wulkowicz
 
Originally posted by Stumper

We got the idea because tight crotches with included bark sometimes fail catastrophically.:rolleyes: Granted -most of them don't fail- but they are more likely to fail nastily than other unions. Perhaps the trees don't care and merrily grow on their way but human beans hate limbs in their driveways and sudden holes in the canopy of their trees(or worse a third of the tree lying across the hood of their car). I wish Bob would discuss these things in a more reader friendly way instead of being the perpetual protagonist.-or is he just an antagonist?:confused:

Browsing the O.T. forum I saw what prompted Spydy's post. Bob's original post addresses the fallacy of thinking that tight crotches/upright branches are a weak arrangement.-Understood-but since the physics dictate that upright limbs are less stressed/bearing less of a torque load they seem to be more susceptible to failure when an unusual load is placed on them. If you think about it though more horizontal brances break under snow loads and freak winds. The included bark is really another subject (Bob did list them seperately) It is the "monkey wrench" in the upright branch equation. The Upright branch with INCLUDED BARK is the one that may break in an attention getting fashion. Peace Bob-lets keep the discussion going.:angel:


You're correct, they are two differents issues. As a limb moves from a horizontal position to a progressively more vertical angle, the "stress" load on the joint or connection is lessened. The "weight" of the limb is proportionally carried more and more by the vertical trunk until "all the weight might be considered the equivilant of the leader"; all the weight direction is downward, there is no lever in relation to the trunk.

All I'm speaking of here is the civil engineering understandings of structures; columns, beams, and levers. Nicht var?


Please tell me where I am thinking incorrectly according to how you see this first issue. :)



Bob Wulkowicz:



PS: How was this derived? <i>Understood-but since the physics dictate that upright limbs are less stressed/bearing less of a torque load they seem to be more susceptible to failure when an unusual load is placed on them. </i>

Not a criticism or any confrontation, jus how does increasing susceptibilty occur?
 
Bob, The above post illustrates why Brian, Nathan and others are irritated by you. What purpose is served by addressing us all in such a condescending manner? Even if we are all idiots ( a premise which I reject) can you not see that the path to educating us will be much less bumpy if you promote a dialogue based upon mutual respect rather than alienating your audience? If you do not respect us you could accomplish much more by faking it.:rolleyes: No , I do not espouse acting falsely. Despite the old saw about respect being earned I was taught that respect is to be granted freely, but withdrawn if the reciever clearly does not merit it. I keep trying to respect you for your knowledge but you aren't making it easy.:(

Whoops you posted again while I was typing. Much better! Yes I agree with you regarding the physics (even if I disagreed you would still be right-no slam intended-facts are facts). The upright branch is NOT a problem. A tight branch with included bark may be a problem.
 
Originally posted by Tom Dunlap
Gilman did some studies that showed a more important indicator of branch union strength is the size ratio. This is a case where science has confirmed what casual observation has shown. The closer the ratio comes to the magic 1:3 the stronger the union. Attachment angle is less an issue also.

The article was published in the ISA Journal of Arboriculture.

Tom

Anothe aspet of his findings is that the abcense of a seam in the union makes it almost as sturdy as the "U" shaped union. Which brings some extra weight to Bob's efforts to remove said seams by scribing the edges so that they will merge. I've been doing this for about 6-7 years now and have seen some good results.

Another problem, I've been hearing about lately, with included crotches that have seams, is that are an infection path for systemic baterial cankers. We've been seeing a number Norway maples have sudden loss of entire leads/sections that seem to always have a major included union. Jim urinack, a local consultant with pathology tendancies, is one of the sources of theis theory.
 
Originally posted by Stumper

Bob, The above post illustrates why Brian, Nathan and others are irritated by you. What purpose is served by addressing us all in such a condescending manner? Even if we are all idiots ( a premise which I reject) can you not see that the path to educating us will be much less bumpy if you promote a dialogue based upon mutual respect rather than alienating your audience? If you do not respect us you could accomplish much more by faking it.:rolleyes: No , I do not espouse acting falsely. Despite the old saw about respect being earned I was taught that respect is to be granted freely, but withdrawn if the reciever clearly does not merit it. I keep trying to respect you for your knowledge but you aren't making it easy.:(

Whoops you posted again while I was typing. Much better! Yes I agree with you regarding the physics (even if I disagreed you would still be right-no slam intended-facts are facts). The upright branch is NOT a problem. A tight branch with included bark may be a problem.


I have pointed out so many times that I respect people and their opinions, that I get depressively irritated about saying it again. The phrase,"respecting opinions", translates into what when I say something in disagreement with long held ideas?The very attempt to say or think differently, brings instant protests.

I remember the groans of the kids in grammar school when I raised my hand to ask a question. Did they occur for you when you asked questions? I remember the face of the prof in cell biology when I asked a question in a room full of students who were scribbling furiously to catch what might be in the next test. The function of that room was not getting educted and understanding more--the game was to memorize what might be asked in a multiple choice quiz; nothing more. No time for questions; gotta keep to the schedules feeding hollow tests.

I hold those systems and calcifications in contempt; not the people. Those are separate issues. Did you read my stuff on Snap to Grid in the ISA forum? That says loosen up as well, and all the other things there are products of what I'm trying to learn--said aloud--for responses and comments

You flagged the tweaking quality of your post by using icons; that's fine; I understood.

I flagged my response the same way, using the original, "better to see... ", but I couldn't use any more avitars where I wanted because this forum limits icon counts. BTW, any "snottiness" in that post applies to me as well--we all have difficulty in accepting new ideas--and we show those difficulties in many ways.

You are not all idiots; why would I try to craft careful responses for that group? My post was really without rancor or ridicule to you as a person; every line is correct--for each and all of us. And, except in satires, please show me one post, one letter, one project in my lifetime where I was dishonest or manipulatve. They ain't there. But there's a lot of people who resent my insistences, my interferences, my stridencies, my keeping my questioning hand up far too longs, along with the understandable angers of having me succeed when they were sure I would fail.

That is not contemptuous, condesending, arrogant, pompous or devious. That's the world, rejection and mockery for speaking aloud, that I've lived in. And, in my old age, it occured to me, why should it continue? I am not the things I teach. The truth of my views have nothing to do with the package that spews them. If I died tomorrow, whatever value existed would still be present and verifiable.


I work in the arena of different, out of the mainstream considerations; I'm there voluntarily so I ought not to whine. Rotate any of us to the proper angle, and we are all thin-skinned. That's life.

I not only try to explain new ideas, I try to explain in a larger picture why they're difficult to teach. Perhaps "tree care" in the labels for forums here, means really using a chainsaw for most corrections, (healings), "care". If that's the unwritten expectation, I can't really squeeze in, can I?

Perhaps I am my own worst enemy, but undersatnd my reluctance to write as intructed by a hundred different viewers. I can't do it and you can't do it. And if we try, the orginal message gets subordinate to the postures of "politically correct" writing.

RockyJ's posts were innacurate: in reviewing my own posts, I didn't do much at all of what he claimed. Interestingly, those are the excuses now that he won't read my ideas of science and tree care. That's his business--whatever public excuses he wants to give for not reading my science. None of that as his reader's perogative, changes the facts of my perspectives.

I'll go back and edit the post that was proof of my disrespect. What individaul lines are offensive? How condescending is it really to say our collective feet are made of clay. I often refer to my feet as the clayiest of all.

I've tried to earn respect the old fashion way by by working hard, researching, and offering new contributions. How they're received is entirely a different matter.

I stand behind my passions. If I didn't, that would be profoundly disrespectful--to my readers and to the whatevers I might claim make me tick.

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<i>The upright branch is NOT a problem. A tight branch with included bark may be a problem.</i>


You may agree the upright branch is not a problem; most everyone else takes it as a problem by dogma--loose it, it isn't as strong.

Included bark is an important issue, but not as the cliche' we have turned it into.

You did make me think about the differences in the statics and dynamics of a verticalized branch. Trees live in both worlds. Maybe we keep those items separate because the classes for each are held in different rooms?

I'll explain later where you made me think differently; reasons and process... Nothing consedcending, just evolutions of thought.


Bob Wulkowicz (sans crab)
 
As has been mentioned many times, the written word suffers from certain shortcomings. Nuances of meaning can be missed when we can't hear tone, and inflection and see body language. Thanks for your last post. I'm glad that we are still conversing and thinking. :angel:
 
You folks may have enjoyed my episode today with a included bark "V" union flowering plum.

I was trying to get some customers to remove 3 - about 16' tall - that they wanted to top, since they are not in good health anyway, nor in a good location.

Suspecting poor rooting on one, I grabbed one of the leaders and pushed the tree about 7 degrees forward while the roots heaved.

Then, pulling bacl with about 30 pounds of pull, the trunk ripped right down the middle, and I went flying over the sidewalk into the lawn strip with the leader landing on me.

Man, have I got a sore thigh tonight.

Needless to say, that bid today, is bumped to a Monday job first thing to get the debris out of the front yard.
 
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OK? What do I do? If I listen to the arborist, he swears that a wide crotch on a tree is strongest. "Look in the books. They all say that. I'm sure that's the case. I cut out narrow crotches because they're weak.""

If I talk to an engineer, he says the more vertical the cantilever, the lower the load on the joint. "Just look at it. Most of the weight is downward into the trunk. It's not trying to stress the joint or rotate the tree."

They both sing out in unison: "This is the strongest connection," while RockyJ continues his a capella rendition in the background of yet another Python song.


I'm befuddled about who's right. Is it one or the other; or both?



<IMG SRC="http://users.rcn.com/bobw.enteract/cantilevered3.gif">


<hr>

Scientific debates before we had email:

http://www.intriguing.com/mp/_video/fish.avi




Bob Wulkowicz :cool:
 
i've always kinda taken the length and weight as the potential leveraged load; then the angle it is pitched at as the percentage of that potential accessed. 3 or 9 o'clock as maximum.

So angle would be load on joint.

Then how far from vortex of given angle that fibre came across from one leg to the other, as to how much strength in the leverage of the support of the jointto apply to the leveraged load. Whereas bark tracing down inside a joint indicates that even though the eye says that there is high binding of fibre bakc and forth between the 2 legs, the fibres are actually running parallel/ not giving leveraged support.

Noticing also, that the farther from the vortex of the 2 legs in angle their is crossing fibre gives more leveraged support; and also, that there is more space to fill with that leveraged support. Even though it takes much less fibre at that point for the same strength as fibres closer to the vortex of the angle; there is much more room available for this better support.

Whereby the load is determined by the angle x length x weight; and strength to support that load is determined by the leveraged placement of the crossing fibre. i've always thought that the 3:1 werks, for one leg at that point can be maximized columnar wise, then encircle the minor to give support that way; at same time grabbing stronger anchor for major leg, as well as no competition for terminal role. Or something like that; as i tried to make sense of it all.

So i see 2 seperate factors:alien:; and am waiting for how to adjust cambium with this scribing, to allow more leveraged support in such a union; and if there are seasons of year or life to apply it in, and not.

The examination of the suddenly loaded vertical that was never exercised to strengthen (every action has an equal and opposite; ie. growth?) is very strong.

And find all of this ....absoulutely fascinating captain!

Spock out


My new dawg was to be Spot but is Spock(has pointed ears); so we have "come in Spock, please come in Spock", "Spock out"; and it also makes him one stupid Vulcan S.o.B., and his ma one stupid mother Vulcan S.o.B.! Imagine we'll get a lot of mileage outta that!:eek:
 
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As implied/stated in Spydy's previous post and in one of mine earlier in the thread. The presence of compensatory growth is a factor in the strength of branch unions. How to calculate it is a question I don't know the answer to. Horizontal branches form large collars. The branch is in sort of a socketed union. In the worst case in which horizontal branch is loaded to failure it typically fails at some distance out from the trunk. The upright branch loads the branch union with much less torque (as long as we are talking about static conditions). The upright union tends to be one of diverging trunk fibers-the "roots" of the branch lie on the surface of the trunk and continue down it much further than the fibers in the horizontal branch with its supporting "socket". Saying that the upright branch union is inherently weak is wrong-it doesn't match with the physics involved BUT the upright union is one in which it is easier to induce splitting and fiber tearout on the trunk. When branches fail (and both types DO FAIL) the upright branch/tight crotched union typically fails more dramatically with greater visual impact. We as an industry sometimes use the wrong words and inaccurate terminology to describe what we observe.:(

Like Ken, I to want to learn more about correcting included bark unions. I can visuaize it on young trees/branches but at what point does it become a fools errand? When 1/3 of a mature tree has a union with large ammounts of included bark then what?:angel:
 
There are 2 different types of branch unions. Gilman calls the type wherethe 2 buds start out together, pith conjoined codominant. because the wood on each is the same. There is no true collar, or protection zone.

I find the use of codom' to be confusing with it's first usage in talking about leads in a tree. So i call these unions "primary branches". they can be stout branches that compeat with the crown, but are not leaders in the finest of sences.

A secondary branch has a separate pith, and the collar and protection zones because the branch wood grows first then the trunk wood grows around it.

Trees being self optimizing organisms gan ad wood to react to the stresses of loading. The problem with the included union is that the fibers do not always join together, ermovin the ability of loacalized optimizaton to compensate. There is a defect, or fault in the "design".

So it is the nature of that speciffic union that causes the defect, not the "A"-"B" dychotomy we we decalre. That is where the dogma takes over from reason.

I'm not advocationg removal of all tight unions, as I do not advocate the removal of all crossing branches (or low limbs ther Mikey boy:p) each pruning cut should is an irriversible decision that should be taken into concideration with the tree as a whole, the peoprty and the clients needs. Some times it is just too late int the trees life to remove the weak union, it may be that removing it will cause worse "harm" to the tree for other reason then leaving it. If it is a sugar maple then 90% of the major unions may be tight V-like formations.
 
Bob's drawings are thought provoking, to say the least.

He should have included a third possibility which would be limbs with attachment angles that face downward like those on an old Norway Spruce, or the limbs on the lower half of a Pin Oak. These puppies never break off.

The implication is that limbs with narrow crotch angles are more upright and therefore put less pressure on that attachment point to the tree. This is true in many cases, in addition to this, the weak attachment would allow more movement at that point, and this would cause slowed growth of the limb and comparatively more wood to be added at the point it is flexing. The tree would compensate for the problem on it's own.

This sounds good on paper, but why is it that included bark is the most common failure we see?
We also see decayed wood fail, and once in a great while even sound wood, but almost never a wide angled crotch with sound wood.
 
Originally posted by Stumper

Like Ken, I to want to learn more about correcting included bark unions. I can visuaize it on young trees/branches but at what point does it become a fools errand?

Yep, I understand the basic theory, but not sure how to put it into practice. Scraping through the bark to the cambium with a sharp blade on a young tree is one thing, but a 2' diameter codominant fir, big silver maple, or even 8" Japanese maple trunk seems another problem. I keep thinking that some sort of kerf would need to be cut out to give the wood room to join together into a strong union. Or that the thcker bark on big codominant stems would need to be pulled out so the wood could meet and grow together. But that would create a wound. A much smaller wound than cutting the whole branch off though, and the tree would still have all those leaves to contribute to healing over the smaller wound.
 
I was excited to hear JPS say he'd been doing this for years. Living only a big shot's throw or two away from him, I'm hoping he can show me a few of his older atempts, or at the least share his methods and any problems he has had.
I have a digital camera, and I might be able to find someone who can climb up and photogaph the work, hopefully we can share on this thread.
Are there any other photos of this work?
 
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