Good source for pruning education?

[Daniel]

Guy and I have our differences too. It's not all winks and smiles. My perspective on pruning seems obvious and logical to me. Guy gets it and it's obvious to him too. BECAUSE HES BEEN PAYING ATTENTION TO THE TREES. Gilman doesn't get it which makes about as much sense as Pete Donizelli sideloading a lightning-struck tree with 4 wraps.

For example, when asked about the "1/3rd rule", which states to only prune back to a lateral stem that is one third the diameter of the parent stem, otherwise to remove the entire limb, Guy will come out without hesitation and tell you there is no science to support that rule. It's a myth that has been busted for over thirty years, but the industry hangs on to this complete misinformed teaching. Guy teaches you can cut back to any little sprout after storm damage, or even no sprout, nothing but a node, which is a better option than removing the entire limb.

In this video, it should be obvious to anyone with a bit of sense and experience that Guy's teaching on pruning damaged limbs is correct and we should allow the tree a chance to sprout back from the stubs of broken limbs.

Common sense trumps science. When the science is weak or non-existent, Gilman doesn't have the heart to rely on common sense. When asked about the one-third rule in the below video his reply is gibberish. He says "when in doubt take it out"...WTF does that mean Ed? Does it mean to take the whole limb out? Or does it mean you can make a reduction cut larger than 1/3 the diameter? Why doesn't he just come out and say that rule is nonsense, and we should feel free to remove more of the branch than the 1/3 rule would allow, even if that means taking it back to a stub, rather than removing the entire limb.

To be fair to Ed, he does talk about sprouts as"our friends" and indicate that we should try to save them in this part of the video:

And you want to give Gilman a pass on not being familiar with the European pruning standards? Your analogies are weak. This man is supposed to be the foremost expert on pruning in the US. And he hasn't bothered to even look at the European standards. THAT IS TOTAL BS. You fell for it. Which calls into question your intelligence.

The European standards talk about things like leaving lower limbs on the western side of trees in open areas, to protect the trunk and root zone from overheating in the late afternoon summer sun. That's just common sense to me, but Gilman.. he's got zero on the subject. Guy, on the other hand, is happy to discuss the pros and cons of the US vs European standards.

Maybe he should write an article about it.

 

[JaredDTS]

For the 1/3rd rule, is it not true that cutting a 10" diameter branch will take years to heal, in the meantime causing decay, allowing insects into the tree and potentially creating a hazard? Thats why most any pruning advice you see suggest creating the structure of the tree when its young and avoiding pruning branches over 5-6" in diameter let alone 1/3 of the tree?

 

[Daniel]

We need to make a distinction between making cuts on the parent stem, these are target cuts as taught by Shigo, and making reduction cuts, which are cuts made to take the ends off limbs.

Gilman defines reduction cuts as cuts where the larger side of a branch union is removed and the smaller remains.

When you make a large cut, over 4", on the main stem of a tree, the resultant decay can destabilize the entire tree, because the decay is in the main stem that has to support the weight of the top and remain strong enough to hold up against the forces generated by wind, rain, snow, ice etc.

When you make a 6" cut on the end of a long horizontal branch, there is only the remaining end of the limb, which may be only an inch or two to hold up. Even as that smaller limb grows, it's never going to create the weight and force generated by the entire top of the tree. And so even if the resulting branch is weakly attached and fails, the tree survives and the threat to property is usually insignificant.

 

[JaredDTS]

I may be confused but I think that's just called weight reduction which is pretty standard.

 

[Daniel]

Weight reduction is a good name for it... pretty standard in my playbook.. when Gilman is asked about it he doesn't call it standard or promote the benefits much. He does the opposite, saying he doesn't know how to define it, and there are no standards, guides, or tables on the matter.

Gilman should be taking notes...

https://youtu.be/PtfpSpIWWrY

 

[Daniel]

Thats why most any pruning advice you see suggest creating the structure of the tree when its young and avoiding pruning branches over 5-6" in diameter let alone 1/3 of the tree?

just for clarity...

the one third diameter rule is wrongly applied to reducing limbs and does not refer to 1/3 of the tree

 

[Bart_]

I gave a yeoman's try to inhaling the Gilman materials and found the main objective to be to train a tree to have a central leader. But what about trees that inherently never seem to have a central leader? Silver maples and locusts come to mind. When the whole tree consists of "lateral extended whatevers" at varying angles from horizontal, then?

Are now end weight reduction and crown height reduction mushed together?

Do you think Gilman would be offended if he was sent reference to basic engineering loaded beam stress analysis? It's what he's getting at with his bending comments, and if he's a sharp guy maybe he would pick up on it like a fish to water.

I always find such trees in various states of internally stripped or lion tailed. Hard to do any more work to and miserable to climb unless you set a line right to the lion's tail tuft.

Just venting. Maybe I contributed. Don't know.

 

[Daniel]

Do you think Gilman would be offended if he was sent reference to basic engineering loaded beam stress analysis? It's what he's getting at with his bending comments.

I think he's referring to the way trees fail in wind storms. The one time I actually saw it happen, the tree was a decent-sized willow and it was whipping back and forth in the wind. SO much so that the branches were touching the ground on the forward whip and then the opposite branches were touching down on the other side of the tree on the return. It whipped back and forth a few times until it broke.

So Gilman talks about branch reduction causing less bending, therefore less of the whipping motion that causes failure. He's reaching for a complex answer when the simplest of answers is all that's needed. Removing weight from branch tips is removing the most leveraged weight and thus greatly reducing forces on the branch stem/union, as the leveraged weight of the limb is multiplied by wind, rain, and snow/ice loads. It's simply common sense. There is no complicated answer needed. The fact that he is reaching for a relevant theory, calls into question his aptitude for common sense.

He then goes on to say that "you could make a case that the less bending of the limb puts more force on the base of the tree".. CAN HE REALLY BE THAT STUPID?

 

[Daniel]

Kevin,
I found this nice video of yours on reduction pruning to subordinate co-dominant stems.

There aren't many examples of such on YouTube.

It's a good video for showing the options and purpose of subordination on a mess of a tree. The only slight difference in my perspective to offer is that you can keep a lot or sometimes all of the smaller laterals and just shorten the tops. The key for subordination is to shorten the tips. After that, the tree will retard the growth in the shortened limbs, which pretty much solves the problem. Some of the side limbs you cut off, before taking the main upright could be used as terminal growth on the subordinated limb, which prevents the wound from being right on the dominant remaining upright stem .