Retrenchment Pruning

Jamie Myers

Has anyone heard of this? seems very odd

Sean Freeman

Retrenchment pruning page 4

coronetcuts_naturalfracture.pdf

Sean Freeman

For those that like graphics;

Guidance Diagramme[1].pdf

treeseer

I think a lot of Fay's work with risk management, but his "environmental arborist" group seems confused on the role of wood-rotting bugs and crud. I have seen NO evidence that these organisms cause trees to live longer, only that they coexist. They and the ecologists have only noted correlation, which far too often is confused with proof by overeager academics.

See Gilman's look at reducing trees that are confined or declining. "Retrenchment" to an arborist means cleanly cutting back to an "inner crown" to preserve it, not to make homes for wood rotters.

Reducing - Pruning - Landscape plants - Edward F. Gilman

Sean Freeman

Not really sure, not noticed that before....

Eric Frei

Question.

I know and see that Gilman's reduction process is cutting to target.

However Fayes does not.

I also understand the meaning of retrenchment pruning to be reducing the die-back crown to a smaller inner crown. As the veteran tree ages, becomes stag headed, a new inner crown line is exposed. This is derived by taking a symmetrical view of a lower crown... debate-able arboriculture though.

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Garry Brockley

a couple of years ago i tried using fayes techniques on a bird cherry but the end result was it looked like i had just put a hedge trimmer over it i didn't like the look personally, i find he pays less attention to cutting to target and when you get to the most severe forms the tree looks completely topped, hence why i personally try to work to gillmans standards, more aesthetically pleasing and uses direct target pruning.

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treeseer

True. There are even formulae for how long to leave a stub to maximize its habitat value. 3x or 5x the parent, depending. Symmetry is one factor for choosing the best location for the cut, but vitality comes first imo.

There is a lot of really good stuff in Fay's work, but this habitat thing I do not understand.

Sean Freeman

Hmmm whats not to understand?

treeseer

Why should we intentionally increase trees' injuries and instability just to create habitat for woodrotting organisms?

Sean Freeman

To preserve and protect rare and threatened species of other organisms just as important to the continued function of the ecosytem as trees...as i say whats not to understand???

Nobody is suggesting every tree is managed in this way, its a specific approach in specific circumstances.

treeseer

Which of these microbes has been reliably documented as threatened?1. How did you quantify the ecosystem value of this yet-unnamed microbe as equalling that of trees?

2. How much is the contribution made by ancient trees vs. woodrotting microbes to the globe and to humans weighted in your weighting of "ecosystem value"? Is it just a matter of "Existet ergo bonum est; it's there, so it must be good?"

3. Ecosystems are more resilient than a house of cards. Other species fill niches, and nature marches on.

Yes these microbes coexist with long-lived trees, so yes these microbes correlate with tree longevity. But where is there any indication that microbes CAUSE tree longevity?

Just asking; I don't know the answers.

As you said in the Enviro Court thread, ecologists' opinions carry great weight in oz (and the UK), but their focus is not on tree biology.

Sean Freeman

It seems (perhaps) like each of us choosing what it is we like in the environment around us then deciding that it has no significant connection to the parts of the environment that don't seem so worthy of our concern.

For me there is no seperation between the trophic levels in the environment around me, they are all intimately linked often in very non linear ways....

Does it matter if we do nothing to protect fungi because we feel that trees are more valuable than fungi...well apart from the intimate connection of fungi to trees, a connection that certainly exposes the weakness of defining them as simply saprophitic or parasitic, I see very strong correlation between holding such an absolutist position and those who have at times claimed there is no problem in failing to protect endangered animal and plant species in say the Amazonian rainforest since there are no obvious uses for such species....now I feel confident that is NOT what you think Guy, so perhaps I'm drawing an unfair comparison.

Guy the fungi I'm thinking of are listed as rare in Europe and have been for over 10yrs not sure what else I can say, I don't do the flora survey work for the EU or the UK but the fact that these particular species are recognised as being rare and threatened within the community of scientists that work in the field of mycology and ecology in Europe is enough for me....

Bit like trying to argue that the RE mapping here in Oz is wrong (RE Regional Ecosystem) sure you can argue that and in some very localised situations maybe have a case but good luck because the weight of researched work is in the published work (ie the mapping).

The same is true for the beetles and other insects, if you want the full list I suggest going to the ATF forum or the woodland trust site, or the UK forestry sites or any of the European mycology sites or the EU urban forestry sites.

Like a great many of our conversations on the internet we would have very few meaningful differences if we could sit down and talk through our personal perspectives face to face, since the certainty and clarity of thought that the written word tends to portray is far from the truth for either of us.

treeseer

Sean, I also see value in the ecosystem complex as it is, but still for me all species do not have equal rights.Yes I acknowledge that they do change strategies, but for me even a potential parasite should not be invited into the tree.Well me neither since I have no time to see what this really means. I suspect that if they looked harder they would find a lot more, and I know that "rare' is a long way from "critically endangered". Maybe some day I will be more enlightened and in a specific situation that calls for the specific approach of damaging a tree to help woodrotting microbes.

Until then, I can't see intentionally damaging trees for that purpose. Retrenchment pruning for this arborist is simply reducing trees in decline to an inner crown, so they live longer.