Dead Wood

tom_otto

New Member
A couple of years ago I asked Tom D. if he would remove the 'Deadwood' thread from this forum because I was tired of seeing it every time I logged into Treebuzz and felt bad about some folks getting upset with the notion that leaving deadwood in trees which didn't pose any risk to people or property might be a good idea. Well, now I'm really happy to see that this topic is still alive. I want thank everyone who contributed to this thread as it has certainly been an interesting discussion.

Also, I wanted to add my two cents....

The body of scientific literature that even begins to address tree physiology and species specific morphological and phenotypical variation suggest that we (scientist, arborist, horticulturist, etc.) don't really know what happens inside a tree or any vascular plant. Shigo truly was a pioneer, but he really just started the conversation. There are just too many actors, i.e. endo- ectophytic fungi, micro- and macro-arthropods, insect/vertebrate associations,etc...
 

guymayor

Well-Known Member
[ QUOTE ]
A couple of years ago I asked Tom D. if he would remove the 'Deadwood' thread from this forum because I was tired of seeing it every time I logged into Treebuzz and felt bad about some folks getting upset with the notion that leaving deadwood in trees which didn't pose any risk to people or property might be a good idea. ...

[/ QUOTE ]

While others felt bad about *you* getting upset about removing deadwood for tree health reasons. Trees are property; decay poses a risk to trees, ergo removing decay saves property aka value. Yet another example--dead branch rotted, rot went into stem.
 

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It is sometimes good to revisit things that were written some time back...it is always a shame when we cannot see the importance of acknowledging that absolutes don't fit the real world.

Decay sometimes poses a risk to trees, sometimes it does not.

It is sometimes possible to be confident that removing decay saves property, sometimes that claim has less basis.

Tom I would agree with your statement
"Shigo was truly a pioneer, but he really just started the conversation. There are just too many actors, i.e. endo- ectophytic fungi, micro- and macro-arthropods, insect/vertebrate associations,etc..."

Personally I feel that passion and emotion are essential things but the conversation should not be stifled by absolutism from any quarter, it detracts from the value I find in these boards.
 

guymayor

Well-Known Member
What absolutism?
"All decay poses a risk to trees" would be absolutist.
"decay poses a risk to trees" is not.

Below (the end of the attached)I listed 4 reasons why deadwood imo should NOT be removed, so you know my view on this is not absolute. In the months since you first saw it, has anything occurred to you that you would want to see added, amended, altered?

Does absolutism (should there be any) stifle the conversation, or stimulate it? It depends.
Relativism stifles conversation, and arboriculture.

Pruning Deadwood: Which, Where, why?
Dead branches are traditionally removed from trees to lessen decay moving into the parent branch or stem, improve air movement, increase stability by lessening load, ease access for climbers and some wildlife, and lessen risk and litter nuisance, among other reasons. Beauty may be in the eye of the beholder, but most clients, as well as most arborists, seem to enjoy the view of the living tree’s architecture more after the dead parts are not blocking the view. However, dead branches can also contain value to the tree, when they provide benefits such as:

Resource translocation. Some recently dead limbs may still have ‘juice’ stored inside, containing stored resources that are still traveling downward. (These resources are a reason that some object to the term “deadwood”.) Large branch removal can be done in stages to allow for this movement, which can also result in a protection zone being formed at the final cut. Or the snag can stay, when removing it would speed trunk decay.
Support. Dead branches in dense evergereens may be holding up neighboring branches above. This support can prevent breakage as it increases sunlight to and air flow around living branches.
Habitat. In trees that compartmentalize well and have no major disease concerns, dead branches are retained because some organisms find niches in branches that are not in stems. Spiderwebbing on bark, between twigs—and between trees!-- can catch aphids and other plant pests. Dead branches that protrude from the crown provide perches for raptors and other valued birds.
Load Damping. Branches, living or dead, in the middle of limbs keep them wiggling in many directions, not wobbling and jerking and breaking. This is why pruning standards advise against “liontailing” branches. On a larger scale, dead branches in the middle of trees can absorb load and improve stability.

The function of deadwood as habitat is ultimately realized when it hits the ground and recycles. Leaving dead branches to border natural areas can be aesthetically pleasing as they fit naturally into many landscapes. Clients appreciate the entomo-myco-arboricultural role these pruned branches play by increasing habitat for soil microflora and microfauna. This brings our account of pruning for habitat finally down to earth. A more conservative approach to all tree associates great and small can help our businesses, our clients, and the living world around us.
 

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Guy I am not interested in editing your writing I certainly accept that you have indicated an awareness of the role of deadwood in a broader ecological view, but that is not the message you conveyed (to me at least) in the quoted text;

"Trees are property; decay poses a risk to trees, ergo removing decay saves property aka value"
Contained no caveat at all.

You statement "relativism stifles conversation, and arboriculture" makes little sense to me..if you have the golden mean good for you, I'm sure many (including me) would like to hear about it....in the mean time (yes poor pun) I will continue to be as honest as I can be and as clear as I can be about what I know and what I don't and try hard to avoid messing either up.

In the past I have mistakenly used the term essential to describe aerial deadwood habitat of small diameter, this was an error since although it can be important (in very specific circumstances) it is not 'essential' in strict ecological terms.

I am not a qualified ecologist I know you have (since in the past I have provided you with) a reasonable number of email contacts to researchers in the field of invertibrate ecology all of whom have published papers on the topic of the relationship between these insects and deadwood.

I am not a qualified mycologist but if I were to consider writing about the relationship between fungi and tree hosts I would hopefully take the time to share my views with someone who was; I believe both Alan Rayner (University of Bath) and Lyn Boddy (University of Cardiff) have email addresses.
 

guymayor

Well-Known Member
Thanks Sean;

Lack of caveat does not mean absolute, does it?
And lack of alternative suggestions does indicate some lack of horror at those very *specific* roles of deadwood in tree health. Maybe someone else will suggest additions to that list.
Those ecology and Rayner/Boddy works are familiar, and we've already gone over what was seen--coexistence--and not seen--codependence. not sure how interested in the trade those folks are but sure; I'll fwd per your hint (telling them you put me up to it), but will not hold my breath waiting for reply!

You and perhaps others who see some yanks as too prone to messing things up will be glad to see that the Rayner/Boddy work was cited and accommodated in Gilman's pruning guide 3rd edition.
 

wyoclimber

Well-Known Member
I look at work I do in an urban setting and work I do in a forest setting in an entirely different manner. Trees do not need our help. They have been doing fine without us for a while now. I believe that our responsibility is to manage interactions between trees and people (or their houses, cars, campers etc...) in a way that is mutually beneficial to the trees and the people. If we can reduce risk in a tree for people and their property and do it in a way that is healthiest for the tree we are protecting that tree from its worst enemy, the uninformed homeowner (shudder) or worse, the redneck with a chainsaw, a ladder, and a pickup (That tree is just gettin' too tall, let me take a little off the top for you).
Well thats my two cents. Better stop before I really get ranting.
 

guymayor

Well-Known Member
Sometimes it petrifies, as in many oaks and some pines etc. ime. Lots of research in Sweden and Tasmania etc. about habitat values in dead branches, in those regions. I learned a lot thru bloody arguments with sean and some brits on this. we've recovered, mostly, and we're all still learning. I used to feel guilty about removing trees, now I feel guilty about removing dead branches and the habitat they give birds and spiders and godknowswhat. putting habitat back one way or another eases the anguish, or I'd have to quit pruning altogether. from page 8, if you joined late. it aint great, and it's out of date--there are other reaasons i forgot:

Pruning Deadwood: Which, Where, why?
Dead branches are traditionally removed from trees to lessen decay moving into the parent branch or stem, improve air movement, increase stability by lessening load, ease access for climbers and some wildlife, and lessen risk and litter nuisance, among other reasons. Beauty may be in the eye of the beholder, but most clients, as well as most arborists, seem to enjoy the view of the living tree’s architecture more if dead parts are not blocking the view. However, dead branches can also contain value to the tree, when they provide benefits such as:

Resource translocation. Some recently dead limbs may still have ‘juice’ stored inside, containing stored resources that are still traveling downward. (These resources are a reason that some object to the term “deadwood”.) Large branch removal can be done in stages to allow for this movement, which can also result in a protection zone being formed at the final cut. Or the snag can stay, when removing it would speed trunk decay.
Support. Dead branches in dense evergereens may be holding up neighboring branches above. This support can prevent breakage as it increases sunlight to and air flow around living branches.
Habitat. In trees that compartmentalize well and have no major disease concerns, dead branches are retained because some organisms find niches in branches that are not in stems. Or on branches: spiderwebbing between twigs can catch aphids and other plant pests. Also, dead branches that protrude from the crown provide perches for raptors and other valuable birds.
Load Damping. Branches, living or dead, in the middle of limbs keep them wiggling in many directions, not wobbling and jerking and breaking. This is why pruning standards advise against “liontailing” branches. On a larger scale, branches in the middle of trees can absorb load and improve stability. If you watch trees on a windy day, you’ll see limbs dance in time with each other, brushing against each other as they whirl and twirl. If they don’t brush against each other and make some contact, they tend to go out of control—kind of like humans, in a way. When pruning we change that dance like choreographers, cautiously considering dose and timing.

The function of deadwood as habitat is ultimately realized when it hits the ground and recycles. Leaving dead branches to border natural areas can be aesthetically pleasing as they fit naturally into many landscapes. Clients appreciate the entomo-myco-arboricultural role these pruned branches play by increasing habitat for soil microflora and microfauna.
 
Dead branches are traditionally removed from trees to lessen decay moving into the parent branch or stem,.
My knowledge of tree biology is pretty rudimentary, as is my knowledge of mycology, soil biology etc. Decay moving into the parent stem always seemed to me like the best reason for removing the deadwood from a tree when considering the health of the tree. However, for example, what if an interior branch died because of a lack of sunlight and it remained in the canopy? Wouldn't the fungi that would eventually decay this branch (assuming that it does decay), be saprophytic, and therefore be unable to colonize the livewood in the parent stem? As I said, my understanding of mycology is extremely limited, and I'm asking this question in the hopes of getting a friendly clarification without any judgment or condescension. Thanks

Chris
 

evo

Well-Known Member
There is what is good for the tree, and there's what's good for the ecosystem/forest... As for your question regarding fungi. There are some cases where some species of saprophytes can become pathogenic, and there are some pathogenic fungi that will decay dead wood. It all depends.... Speaking generally however if the tree is in good vigor and can compartmentalize well it can resist pathogens... It's not unlike us (people) where we are constantly bombarded with things that can make us ill.

For me it depends on the species and the setting, a few weeks ago I literally pruned the dead wood cornet style and retained long broken stubs with jagged ends... This was along a 1/4 mile driveway through the forest, and these were forest trees. The dead wood was very thick and twiggy, and posing some hazard for the home owner walking the dog, and road traffic. The trees get to live their naturalish lives and the hazards are mitigated while retaining habitat. While the other trees closer to the house are regularly dead wooded when needed.

I have a fair sized Austrian pine in our front yard where a large branch/lead broke out that's about 8" thick long before we moved in, and I retained it. However we have a huge owl population around our house... Weekly there would be a great horned owl roosting in the pine. I decided to do a through dead wooding to the tree, down to hand snip sized pieces... The owls didn't like it, and I haven't seen one in that tree since, but they do still come around the adjacent trees.
 

guymayor

Well-Known Member
Yes habitat is a very worthwhile objective in many areas.

Hypoxylon is one fungus that can break walls in species like willow oak. But on healthy live oak or post oak I'd be less aggressive about deadwooding, as they can form rings of woundwood at the base, with the dead branch still attached.
 

moss

Well-Known Member
Was doing a deadwood/hazard prune on a large backyard Norway maple last week. First off I noticed a bunch of small rip cuts from a previous reduction pruning with a pole saw, they were not closing or compartmentalizing well, that's another subject. At one point a pair of Downy Woodpeckers mated right in front of me. 10 minutes later I'd reached an area in the crown where a vertical leader had snapped off. The remaining 10 foot section was dead down to a union. As I removed the big hanger (still there) one of the woodpeckers reappeared at a brand new nest hole at the top of the dead section. I left the dead section on the tree. Later I told the homeowner that he had an active woodpecker nest and I would take the remaining dead section out after the young were fledged. He was quite happy that I hadn't taken out the nest. This adds nothing to the deadwood science but shows one way to deal with wildlife habitat in residential trees. Leave it, educate the homeowner, take it later when it's no longer being used. For this old maple there were already plenty of hollows in the tree, the deadwood removal was for aesthetics and safety.

 

Daniel

Well-Known Member
decay does not necessarily pose a risk to trees...
the idea is ridiculous...
its like saying a scratch poses risk to human beings...
 

guymayor

Well-Known Member
Nice!

The OP was strange; "I've read almost all that Shigo published and understand that CODIT will happen around senescing (sp) branches regardless of whether or not the dead branch is still attached. "
Since Wall 4 of CODIT includes closure of the wound, I'm not understanding that assertion. Only in rare cases Walls 1-3 are enough.
Forest Service
U.S. Department of Agriculture
Agriculture Information
Bulletin No. 405
July 1977
 
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