Reductions.. is 10% too much?

[Lignotuber]

From Erk Brudi research

 

[Bart_]

Unlike traditional engineering cantilever beam stress max at the collar/base I recall often seeing (partial)) shear failures about 20% out the length of the branch. Was that the same area as the critical fracture zone referred to?

is this the source material? no Erk Brudi mentioned http://www.ecosync.com/tdworld/Branch Failure Investigation.pdf
edit - author Detter works with Brudi

ps I remember finding a trove of Gilman stuff online years ago.

 

[Lignotuber]

Unlike traditional engineering cantilever beam stress max at the collar/base I recall often seeing (partial)) shear failures about 20% out the length of the branch. Was that the same area as the critical fracture zone referred to?

is this the source material? no Erk Brudi mentioned http://www.ecosync.com/tdworld/Branch Failure Investigation.pdf
edit - author Detter works with Brudi

ps I remember finding a trove of Gilman stuff online years ago.

Not sure, I haven't read through it in a while. Link doesn't want to work for me.

 

[evo]

@Lignotuber Thanks much for digging that up along with the source.
This brings it back to my train of thought.
If you can improve the stability with 15% reduction by 40% do you really need to?

I don’t really care about 15% blah blah, and 40%
In a region with 100mph windstorms do we need the tree to hold together in 140mph windstorms? Or take it to static load.
In an area that gets ice storms, if the limb regularly sees 10lbs of ice does it need to endure 14lbs?

What does 5% get?

 

[Lignotuber]

@Lignotuber Thanks much for digging that up along with the source.
This brings it back to my train of thought.
If you can improve the stability with 15% reduction by 40% do you really need to?

I don’t really care about 15% blah blah, and 40%
In a region with 100mph windstorms do we need the tree to hold together in 140mph windstorms? Or take it to static load.
In an area that gets ice storms, if the limb regularly sees 10lbs of ice does it need to endure 14lbs?

What does 5% get?

Thanks, sounds like your on the right train of thought with all this. Snow and ice are kinda out of my comfort realm but I generally would ask do we even "need" to do anything. Is there a risk that exceeds the clients threshold? How frequent are these failures and to what size diameter wood? Nature has been doing this a long time and failures often provide habitat. Idk, I would say to take moments to observe what happens in different scenarios with curiosity and let your regional experience guide you. Perhaps you could even perform some static pull tests every once in a while.

 

[Bart_]

I just nipped off a 15' 20 degree upslope maple branch that had a years encapsulated horizontal shear crack 90% across, shear crack about 1 1/2 ft long. Ironic. Was showing decay discolouration propagating from the crack. HO said the branch just died.

Are weather history stats somewhat of a moving target these days? Aren't California HO's getting cut off from house insurance lately?

 

[Lignotuber]

I just nipped off a 15' 20 degree upslope maple branch that had a years encapsulated horizontal shear crack 90% across, shear crack about 1 1/2 ft long. Ironic. Was showing decay discolouration propagating from the crack. HO said the branch just died.

Are weather history stats somewhat of a moving target these days? Aren't California HO's getting cut off from house insurance lately?

30 year weather history is the "normal" from my understanding. Definitely global weirding lately though.. I've heard some weird stuff of about fire insurance but have not been personally impacted nor know anyone that's dealt with issues other than at times ridiculous costs.

 

[Bart_]

I've come up with Charlie Brown Christmas tree prune to describe a nasty hatrack with about two 3' branches remaining to sprout leaves - on a 50' maple. still waiting on a miracle to save the tree. was a 98% reduction....

 

[evo]

I've come up with Charlie Brown Christmas tree prune to describe a nasty hatrack with about two 3' branches remaining to sprout leaves - on a 50' maple. still waiting on a miracle to save the tree. was a 98% reduction....

Won’t fall over… at least in the next decade until it rots or dies.