Blowing in the wind-Gilman research

Reductons to lesson wind damage is common sense!i do find the research interesting on young trees, i personaly will shy away from reductions unless the tree is mature or veterain and poses a risk to property or in some cases just the later,it needs to be made clear that any pruning needs to be followed by a regime evan if its just a climbing inspection.
The thing that alarms me about such claims is you will be getting a load of hacks on trees doing more damage than good in the long run.
Over here in the uk when we were on call out in storms i could almost say every time we went out it would be populars,crack willows and ray wood ash maybe purple plums but two times out of three it would of been previous pruning that caused the limbs to fail.
Then again,in the uk and we dont get the sort of storms you get!
 
Bustus: "I have been going back and looking at my reduction cuts made several years ago and I'm usually finding several latent buds erupting near a number of these pruning cuts..."

Younger trees resprout more than older trees, so you're not overextrapolating are you?

"they are almost always opposite the branch that was supposed to take over hormonal control (e.g. branch at least 1/3 the diameter of the actual reduction cut)."

The tree does not know about numbers. The 1/3 guideline has to be considered along with more biologically important criteria like angle, orientation, exposure. If your reduction cuts are facing up instead of down, you are provoking the wrong response.

"The net result: several very rapidly growing watersprouts causing MORE problems (rubbing limbs & blocking above development of scaffold limbs) than if I hadn't of made a cut at all."

The Glossary states that watersprouts have a strong vertical orientation. These result when wounds face skyward, which is a no-no imo where avoidable. Wherever the sprouts are in your young trees, they just get snipped in the next pruning cycle, so where's the harm?

Bustus, it may help your pro-thinning campaign if you could post some pictures.
 
Steady on.... I don't believe I stated on this forum that I'm pro-thinning on young tree limbs to initiate their subordination (i.e. thinning to mimic decreasing photosynthate contribution and thus increasing likelihood of BPZ formation)... You must of heard that over some beers in Nashville from my evil twin.

I'm just saying that we (arboriculture community) still have a lot to learn. I have a hard time attributing a particular pruning technique to an end result when "we" have yet to unravel all the natural mechanisms at work under the surface. I'm involved in a small research project now that is showing natural subordination at work on white oak trees that are about 8 years old. Seems that the trees start off with a large number of rapidly growing limbs (large branch aspect ratios) that begin to subordinate themselves as the tree gets older (small branch aspect ratios). As if the tree wants to be keep a number of potential leaders active in case something happens to the central leader. We'll present at MAC-ISA this fall.

I absolutely agree that young tree biology is different than mature tree biology (smaller amounts of hormones have a larger effect, higher live tissue/dead tissue ratio...). All the more reason to be very cautious when pruning young trees.
 
Thanks B. Your observations of self-subordination of young tree limbs, and the need to be cautious, agree with mine. No cut without a reason. re macisa, I didn't see that on the early blurb that just came. hOpe I can go this year.

O and the pro-thinning campaign was underway long before your evil twin had a sip. Those beans were already spilled, so don't get on your twin about breaking confidentiality. /forum/images/graemlins/crazy.gif
 
If one of us were so misguided as to lion-tail a tree, it would reduce its wind resistance, resulting in fewer degrees of lean in the trunk in the terms of this experiment. Five years later those branches will be weaker and longer and more likely to break in a storm. Heading back major branches is also a less than ideal pruning method, and may likely result in a bushy mess. I wouldn’t start creating new problems until I was certain the new technique was valid.

The biggest problem with applying this research is individual differences. To get coherent data, they must have used a homogeneous sample of trees of the same age, species, shape, and health (anybody have the actual article?), which would limit the applicability of their findings. When you compare a group that received treatment with a group that did not, you rely on the differences among those individuals being small enough to see the difference between groups. I would guess that trees in the field, even of the same age and species, are so different as to drown out the effect of the pruning technique described. True, these findings, if valid may be one factor to help inform our skill and knowledge, as Tom says, but I will continue to trust my intuition from personal observations over this kind of rule of thumb.

Neat idea though.
 
I agree.

This research may encourage some to start a policy of crown reduction. Similar debates started after Mattheck recognised and reported the benefits of reduction over thinning in certain situations. But the bioligical needs of the tree, and natural form aesthetics are just as important, plus the practicalities of future management (those that routinely recommend 30% reductions to cover their arse, probably haven't had to reprune something like that 10 years later, with all the dodgy anchor points. A certain Silver Maple springs to mind!).

I dread the effect of policies from safety nazis in a position of authority, that are hell bent on risk reduction to suit our cosseted lifestyles. Aggressive risk avoidance and enforcement manifests itself later down the line like the super nemesis of global warming and terrorism.

I've learned to love and respect those defiant individuals that live on the line between risk, cost and benefit (not just trees either). That doesn't mean taking unnecessary risks that cost other people! (a certain recent thread springs to mind!).

Each individual (tree) needs to be appraised on its own merit and environment. Like Mattheck states, a good medical consultant, isn't the one who looks at your symptoms, reaches for the book and gives you the pills. He is the one who has read the books, had good experience, and uses his intuition to make a decision. The 'clinical eye' usually takes a gamble for the patients benefit.

Few consultants in any sphere are prepared to do that. The bigger issue is misguided legislation that can be used against them by hungry lawyers in court.

Research proves what it wants to prove. It is up to us to use our study, experience and intuition to make the best decision, based on all the risks, costs and benefits. 'Holistic' was the buzz word a few years ago.

I tend to reduce or thin specific branches as I see fit, depending on taper and defects and aesthetics, rather than cart blanche % proposals. But then my clients trust me to do whats best.

Well thats built up an appetite, I wonder whats cooking...... /forum/images/graemlins/hoos.gif
 
In every bit of 'reduction literature/research' that I've read it says that a small crown reduction will result in large gains in stability. No where near that 20-30% amount that gets trotted out. that is the maximum limit that trees in good health seem to tolerate before dieing. There's no reason to ever do that much reduction in the normal course of tree work.

Recipes are good for cooks not arbos :)
 
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No where near that 20-30% amount that gets trotted out. that is the maximum limit that trees in good health seem to tolerate before dieing.

[/ QUOTE ]


Not in the tropics!
 
[ QUOTE ]
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No where near that 20-30% amount that gets trotted out. that is the maximum limit that trees in good health seem to tolerate before dieing.

[/ QUOTE ]


Not in the tropics!

[/ QUOTE ]

So rumi, how far back can you reduce those trees in HI? 15? 35? Maybe that's a solution--get someone to hike up those Albizias and shorten those ends (kidding). What about that cinnamon tree by the building that the utility side-pruned--has it been reduced on the other side to restore some balance?

The Tree Statics folks look at 10% as an amount that yields a good gain in stability. An arborist in Germany writes about consultants there specifying severe reductions, to the point of mutilation.

Yes there is a danger of overdoing it, but reduction cuts on sprawling branches has to be an option.
Overall crown reduction imo has to be saved for extreme cases.

"How big a cut can we make til we know

That too big a cut has been made?

The answer my friend, is growing in the tree,

The answer is growing in the tree."
 
I was kind of being facetious there, Guy, but the point was that in the tropics trees will tolerate extreme abuse (severe reduction, topping) and still bounce back. When I first moved here from Texas I was amazed to see all the topped trees. "My god, they're all gonna die!" I thought. I was wrong.

Don't get me wrong. I am not advocating extreme reductions. However, we do have a little more flexibility with what can be done with a tree in the tropics, and sometimes that can make the difference between saving a tree and cutting it down. Unfortunately, that ability to be more aggressive when pruning leads people to think it's OK to indiscriminately hack trees back. Just because the tree doesn't die, doesn't mean it's a good idea to top it.

Of course, this is all species and habitat dependent. The albizia trees that you refer to, Guy, do very well with reduction cuts, preferably about 4" above the ground ;). As for the cinnamon tree we looked at, it will meet a sad end. Next year it is slated for removal in order to put in a more modern septic system for the Children's Center at the Arboretum. I put up a feeble fight to save it, but couldn't really justify too well seeing as how I am having to closely monitor decay/canker spread in the tree. Hopefully there will be enough sound wood in the trunk that we can use to make furniture of some sort and keep the tree around and smelling good for a little while longer.
 
Leon you're right about a longer growing season (like 12 months) changing treetments. Sorry to hear about the cinnamon--I don't remember stem decay. Maybe I was too focused on that stub. Sure would like to see a picture of it--is it Phytophthora cinnamomi?
 
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