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Guy Meilleur

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Like Murph, I'm looking for thoughts and criticisms on an article, this one on selective heading cuts in the August Arborist News (page 9). The idea was already put forth in TCI mag last spring, but underwent major revision since then so here it is again(no, it's not going away!).

Many authorities, and even ISA pubs :confused: say there is no such thing as a proper heading cut in a mature tree, that heading = topping, that all stubs are bad, etc. I'm trying to kick the door open to hearing any comments, broad or nitpicky.

Like Murph, I know that criticism and disagreement are often needed to move things forward. If you're shy you can email them off-forum. If you're going to ISA-Pittsburgh look at the AREA posters; coauthor Jim Scarlata will be shoing lots of pix (too bad AN could only print two).

Thanks!
 
Well, Guy, I can say this: I have lost at least 2 jobs by recommending heading cuts back to laterals substantially smaller in diameter than the limb being removed. In both cases the homewoner assumed the limb needed to be removed to the trunk, but I offered the Guy Meilleur alternative.

Both homeowners seemed impressed at a solution that could perhaps salvage a large chunk of a large limb. Then they hired someone else willing to cut the whole thing out (I would have cut the whole thing out also, but I think they got the impression that I wouldn't.)

Anyway, I hope your right about this stuff.

Steven
 
The r-evolution in thoughts presented here in this board is part of the waveform of the "Paradigm Shift" in arboriculture all around the world(though, looks like we aren't waiting for the rest!). Brought 180 degrees from topping, stobbing, painting, spiking as the top of art and science to not, not,not,not etc.! The pioneering of Doc Shigo against the stated knowledgebase, and following microscope etc. is pivotal to where we are now.

Time to keep minds open, understand off balance as we are yanked in totally the opposite direction by the higher science that innately seems to ring true somehow. Don't fight nuthin, just relax and see what is!


Orrrrrrrrr, sumetin'like that!
:alien: :alien:

Murph has been contacted to speak at Pitts. ISA too, show new techniques/tools or something i think.
 
I have one of the biggest problems with heading cuts. I have to be in a total different mindset. I have to be told that there are no long term goals on keeping the tree about to be headed. I don't mind the heading cut if what I cut is already dead. I just get a gut instinct thats its bad. It's just not natural but through heading cuts we can achive an orimental goal and nothing more. I don't see any long term health benifit for the tree.
 
Originally posted by BigJohn
I don't mind the heading cut if what I cut is already dead. I just get a gut instinct thats its bad.
John, my whole point was to cut back damaged branches to the first good node below the damage. That means cutting out as little living tree as possible. But I hear what you're saying about a gut instinct; the "stubs are bad" message has been heavily drilled into all of us.
It's just not natural but through heading cuts we can achive an orimental goal and nothing more. I don't see any long term health benifit for the tree.
Only ornamental? Look at the picture of the resprouting tree on page 10; that's horrible-looking to most anyone who doesn't visualize what it will look like in 6 years, after 2 thinnings. The long term is what it's all about.:blob4:

But thanks very much sir for speaking up; I know it will take 6 years of work, and many pictures (wish AN would have printed more!) before there are enough restored crowns for everyone to buy into this. Even then there will be doubters, change is hard.:rolleyes:

Neb buddy, when you were here and kept asking about heading cuts I kept saying nono, let's do the basics first!
Then I blabbed the practice anyway, maybe my bad...So you gave the impression that you would not remove whole branches when the customer wanted them done that way, because you were sure the other way would be better for their tree? Say on, brother!:cool:
 
I think I may be a little unclear on what a heading cut is, BUT I do believe that trees grow for the most part by phototropism- that is to say toward the light.
This is why we see trees with "lumps" on the outer canopy, the interior is too densely foliated to allow sunlight to penetrate and so the interior is defoliated. So what happens is the tree puts growth on the only place available, the outer branches. As these branches grow longer and longer (phototropism) they become heavier and may break off.
Pruning to me means working on a paticular tree with the goal of preserving it's main structure and encouraging it to grow stronger.
This translates into tip reduction in many cases. I cut a long limb back to what I call a 'viable' lateral- one that is at least 1/2 the diam. of the parent limb.
Sometimes there are no or few viable laterals or these same laterals are in the wrong place so i fudge and cut back to smaller laterals.
Why do trees grow to self destruction?
What is the overall purpose of the tree if in it's natural habitat it grows in such a way that it causes it's own limbs to shed out?
I think this question is answered by the trees lifeforce. The urge to propigate is so strong the tree will naturally tear itself apart as long as it can produce and keep producing, seeds.
Or like someone likes to say here at AS:
or somthing like that...
Frans
 
Originally posted by Frans
Pruning to me means working on a paticular tree with the goal of preserving it's main structure and encouraging it to grow stronger. You got it right there, partner. :).
Sometimes there are no or few viable laterals or these same laterals are in the wrong place so i fudge and cut back to smaller laterals.
I don't like fudge the "food":rolleyes: but I do like fudge as in stretch the envelope, break the box, shift the paradigm. (Thanks for making that link, spidey, Kuhn was a man who took the '60's spirit into science, renaissance!) How about cutting back to former laterals or even to potential laterals? Scary territory but it works, and hey if Shigo said 20 years ago that it's cool and ANSI 2001--where you can find the definition of a heading cut--says it can be OK, what else do you need?;)

Tree Preserver
 
If you've got to head, it may as well be done as good as possible.

I just did a tree in Murrayhill in Beaverton. It's a mid to upper class neighborhood on a hill where community rules mean views can't get blocked.

But at least they like to have trees rather than no trees. Even the small trees eventually are an issue there due to the small lot sizes.

I just topped a honey locust to open the required view. Made the cuts the best possible according to what I know.

Not my favorite work though !!

In fact, I'm passing on this one because me and my help both slipped on the slick kinnickinnick ground cover on the steep hill. I don't need the work so bad as to fall and slide into something.
 
In Doc Shigo's "Modern Arboriculture"; at the end of everything, he makes referance to the original playwright of the paradigm.

As the Doc shows these new precepts, he also arms with philosophy, presentation skills; almost knowing were one must go!

After the Z's in the Index, you can find:

"Kicking and Screaming
they resisted being
dragged from the shadows,
of the cave;
out into the light of
Understanding.

Plato's-Cave Alleghory


But, as Daniel faces trying to 'flip' some people to newer methods, face first into some kinda 'paradigm' of resistance; that can be the power to change, for all he has to do is clearly prove something simple that jerks one to the opposite direction off balance. Just like the most leverage point of restraint with a line is to oppostie direction, the opposite cheek. Indeed having such odds against you is one of the strategies for inciting change, if ya can steer that force to your target, not it's natural direction. Such a surprise mental tide can cause attention getting fascination without raising defense instinct, and the talk then begins with open minds according to Franz Mesmer.

Donella Meadows' 12 Leverage Points to Intervene in a System

Notice, thought he power of leverage is indicated used powerfully, here it is done in the mechanics of conversation, as anything else. As the mechanics are........exactly the same but different!


Write On GuyS....
Write On!
 
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overhere in the uk we don't use the trem heading cut is it possible for somebody to post a head cut picture :D
 
In building my site MyTreeLessons.Com i collected as many hot links as i could; then researched more.


One of the hottest finds was the Doc Shigo Sight on Tree Systems . You'd be short changing yourself IMLHO not to soak up #1 and view the Doc's clear logic and style .....

i think running a tree at a high stress factor forces growth strategies grasped at for survival, not strength. Topping/stobbing being one example in over flush of shallow connected output of branchings, the strain of extra callous produced if stob dies and must be swallowed to close etc.; so callous must walk out over it. In the Shigo terminology i beleive callous is expen$ive to tree resources.
 
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what rolla said....im unsure also.
im assuming its cutting a stem back to no growth point and leaving a stub
???
 
Don't you UK guys get Arborist News? Here's the article; should answer questions about definitions etc.

Spydey yeah callus is $$$. The whole point is to make cuts where it will cost the tree the least to close them and gain the tree the most in new, viable branches.

SELECTIVE HEADING CUTS AFTER STORM DAMAGE

December 5th, 2002 was a day that will live forever in tree infamy in Raleigh, NC. An inch and one-quarter of ice put a crushing load on the area¡¦s arboreal resources. Huge limbs dangled like Damocletian swords, grotesque ornaments greeting their owners. Contractors were told that in the course of cleaning out broken branches they had to cut all the stubs back to a substantial lateral. This rule is called ¡§Natural Target Pruning¡¨ or ¡§making Shigo cuts¡¨. They were also told, following FEMA guidelines, to remove trees with 50% crown loss. It was a Catch-23: obeying the first rule would remove so much more living crown, many trees would be removed that could simply be restored.

If arborists wanted to facilitate the coexistence of people and trees, they had to reread the directions, the ANSI Pruning Standards. In ANSI A300 4.20, heading is defined as ¡§Cutting an older branch or stem back to a stub in order to meet a defined structural objective.¡¨ 5.5.6 states that ¡§Heading should be considered an acceptable practice in shrub or specialty pruning to reach a defined objective.¡¨ Since restoration pruning is a type of specialty pruning, the standards seem to allow for leaving stubs in trees for the defined objective of preserving them.

Also, selective heading cuts are routinely made in vine, shrub and fruit tree pruning, bonsai, pollarding and other arboriculture. So how can all selective heading cuts in a big tree be considered improper? This exceptional storm challenged the simplified rules, which seem based on a Cliff¡¦s-Notes reading of the literature. The old ISA seal says, ¡§Science, Research, Preservation¡¨; good words to work by. Preserving trees is the goal; preserving branches is the way to reach that goal. This may mean cleaning the crown of damaged tissue only down to the first good node. As Dr. Alex Shigo said in A New Tree Biology, p. 458, ¡§Topping is done internodal; proper crown reduction is done at nodes, OR at crotches. So the first separation must be nodes¡Xgood, internodes¡Xbad.¡¨

NODES AS NATURAL TARGETS

Cutting to large laterals prevents natural regrowth and takes stored resources away from the tree. Restorative heading cuts are not random or predetermined, like topping cuts, but selected according to biological criteria. But what is a node, and what does it look like? In A New Tree Biology Dictionary, Dr. Shigo defines ¡§node¡¨ as ¡§the position on a stem or trunk that was occupied by the terminal bud and its associated buds.¡¨ Some nodes contain fully formed buds that have been carried along in the cambium as the branch grew.

These buds are connected to the vascular stream and often anchored by compacted xylem, as shown on pages 238-9 of ANTB. Due to their vascular connection, the growth from these buds can be well nourished, and due to the xylem connection it can be well anchored. This dominant growth contrasts clearly with weak growth newly formed on the surface of the bark from adventitious buds. Some botanists also define these growth points as nodes, but terminal bud locations offer a clearer target.

What do target nodes look like on the outside? A bulge just before a decrease in diameter can indicate reduced branch growth beyond a terminal bud. A cut just outside a bulge will also leave a smaller wound, and retain more symmetry and structure. Some raised areas may contain dormant buds visible to the naked eye. Some bumps and bulges may be due to pests, so the surface of the cut should be examined to ensure that is not the case. Wrinkles on branches can be the same swollen collars that once formed around the base of lateral branches. If a scar indicates that a lateral branch was shed at these locations, there may already be preformed lateral buds on the outside. They may also already contain what Gilman and Lilly called the ¡§unique chemical barrier called the branch protection zones¡¨ in Arborist News, August and October 2002. These articles are viewable online.

DANGEROUS DROP-CROTCHING

Locating nodes without laterals may seem sketchy at first, but consider the alternative. Reducing damaged branches back to the center of the tree can increase the danger of windthrow. In The Body Language of Trees, Mattheck and Breloer caution against removing more weight from the windward, storm-damaged side of the tree. ¡§The crown shape and the wind then combine forces to lift the pruned side of the crown, so reducing the normal stress and indeed perhaps transforming it into tensile stresses (i.e., lift!). When this happens, the effective sliding surface between the root-ball and the ground is so severely reduced that the tree blows over far more easily.¡¨

If drop-crotching exposes the remaining branches to more stress and strain, how is the tree safer than if heading cuts were made? The damping effect of limbs, for years thickened by torque, is altered while other branches thicken under the new load. The tree is vulnerable to disintegration while new reaction wood is formed in response to the new stresses. As Dr. Karl Niklas notes in the Tree Structure and Mechanics Proceedings, ¡§When exposed by the removal of neighboring stems, previously sheltered and mechanically reliable body parts may deform or break even under wind conditions that are ¡¥normal¡¦.¡¨

Avoiding decay is another good reason to make nodal cuts just below the storm-caused wounds. Large wounds on trunks are unlikely to close before they start cracking and become what Schwarze, Engels and Mattheck refer to in Fungal Strategies of Wood Decay in Trees as ¡§motorways for decay-causing fungi and bacteria racing into the heart of the tree.¡¨ Our strategy must be to minimize the infection courts we create. Retaining branches that Nature topped also avoids sun injury, defined by Shigo in ANTB Dictionary as ¡§¡Kwhen trees are suddenly exposed to direct sunlight¡KThe bark cambium is affected and the outer bark plates are flattened¡¨. These injuries are slow to seal because the tree¡¦s interior bark is very thin, and the sun dries the tissue at the edge. Big pruning cuts and sun-damaged bark may never seal.

Restore or remove? Where to make the cuts? It depends on:
„h Species- good sprouters and good compartmentalizers
„h Age and vigor of tree, which affects sprouting potential and wound closure
„h Size of wound ¡V smaller wounds = faster closure
„h Available laterals or other obvious nodes with sound wood
„h The need to retain a central leader and weight balance


THE TREE¡¦S RESPONSE

Retaining stems and scaffolds by making heading cuts can minimize sprouting by leaving, much higher in the tree, a smaller surface from which they will arise. Cutting deeper to a lateral may result in the attempted formation of more leaders growing more vigorously from a larger wound. The greater the dose of pruning, the greater the shift in the auxin/cytokinin balance. A part of the cytokinin effect in relieving apical dominance when applied to the bud may be the stimulation of vascular development connecting the lateral with the main vascular system. In The Formation and Development of Dormant Buds in Sugar Maple, Church and Goodman observed that "Epicormic sprouting below the live crown increased as additional amounts of the woody crown were removed...¡¨

When storms upset the balance between roots and canopy, the tree responds by sprouting to restore the balance. The more that is removed from the tree, the greater the imbalance and the reaction. At some point there will no longer be enough photosynthesis and the tree will decline. In The Practice of Silviculture, Smith notes that ¡§Diameter growth may suffer if the live crown ratio¡Kis reduced to 40 percent or less. Reduction in diameter growth slows wound closure.¡¨
 
Prt 2; hey they asked for it; I figured everyone saw the mag.

Aftercare is often very easy but it is important to communicate to all stakeholders that the restoration process requires additional work to complete. The dominant sprouts can be trained to become the new branches. On mature oaks, every three to five years seems about right. During each visit we prune out:
„h Branch sections that have failed to sprout well.
„h Branch sections with rapidly advancing decay.
„h Sprouts that are crowded together and could develop included bark.
„h Sprouts that are not forming a buttress.
„h Suppressed sprouts that are declining or dead.

ON IT GROWS

Some branches that were headed back in 1996 just got their second thinning. They now have three strongly attached, natural-looking branch ends to carry on the growth of the tree. What looked like ugly stubs at first grew into attractive, safe and symmetrical portions of our valuable tree canopy. Some observers initially object to the sight of reduced branches because they are reminded of topping cuts. It may be time for the anti-topping passion to cool a little, so we can consider selective heading cuts without worrying about them looking like topping cuts.

Canopy conservation is the ultimate reason for minimizing crown losses. When nature radically removes portions of our tree canopy, it¡¦s up to the arborist to save what¡¦s left. Trees are dynamic systems. The more of the tree we conserve, the more present and future benefits such as clean air and water we will conserve. As measured by American Forests¡¦ CityGreen software, our urban tree canopy delivers high value that should not be removed without a very good reason. One mature willow oak can recycle over two hundred gallons of water per day. Selective heading cuts on damaged trees benefits the tree, the tree owner and the community.

So think about specifications that require enlarging the holes in damaged tree canopies and risking imbalance, decay, sunscald, and anchorage loss. A ¡§compassionate conservative¡¨ approach calls for the arborist to aim for natural targets, so the tree owner conserves assets. For the cost of three pruning jobs, the expense of removal and replacement can be avoided. So if air masses collide and crush your canopy, you can guide your trees¡¦ restoration by selectively heading for better form.


Guy Meilleur, Consulting Arborist, www.BetterTreeCare.com
James Scarlata, Registered Consulting Arborist, Tree Doctors, Inc.
 
Originally posted by Frans

Why do trees grow to self destruction?

Don't forget that in the old days (pre settlement), trees grew in a forest situatiuon. That means they had trees all around them. In a landscape situation, trees have way more sulnlight around them to phototropate to...
 

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