Daniel
Carpal tunnel level member
- Location
- Suburban Philadelphia (Wayne)
I use 9/16 bits for 5/8 j lags on everything except silver maple and tulip, which get 1/2" holes.. Always a good idea to install thru bolts on anything questionable.
Cabling a spreading silver maple
- Thread starter nuthin_special
- Start date
guymayor
Branched out member
- Location
- East US, Earth
No mention of through cabling with terminal fasteners like rigguy or wedgegrip?
If anyone tells you your proposal isn't "standard practice", ask them which clause--by number-- it breaks.
Chances are, it complies.
If anyone tells you your proposal isn't "standard practice", ask them which clause--by number-- it breaks.
Chances are, it complies.
- Location
- Thunder Bay, Ontario
Agreed that a dynamic cable that low in a tree with a split won't be rigid enough for adequate support. Even if teamed with through bolts below the crotch.
I was debating through rods with a cable connecting before I saw that post. I think it's just too much force to trust to a j lag.
Seems crazy to put this much thought into one silver maple when there are 3000 more in far worse condition that don't get any attention. The squeaky wheel gets the grease.
Thanks for the discussion on this!
Vince
I was debating through rods with a cable connecting before I saw that post. I think it's just too much force to trust to a j lag.
Seems crazy to put this much thought into one silver maple when there are 3000 more in far worse condition that don't get any attention. The squeaky wheel gets the grease.
Thanks for the discussion on this!
Vince
Norm_Hall
New member
- Location
- Wauconda, (Chicago),IL,USA
Perhaps the attachment will help on choosing the hardware. The column marked "Lag Hook" is actually J lags.
I have other interesting documents on cabling with J lags if you are interested??
I have other interesting documents on cabling with J lags if you are interested??
- Location
- Thunder Bay, Ontario
Norm: I'm interested. Can you forward said documents to me by email?
vince
vince
Mangoes
Participating member
- Location
- Greater Toronto Area
6-8 years ago Norm posted some research here indicating 5/8 lags pulled out of sound Red Oak at less than 6000lbs (caveat - numbers as accurate as 6-8 years might allow)
My previous employer cabled alot of trees for school boards.
These two influences produced a policy that all static support systems installed by our team will be anchored with threaded rod through bolts.
We also did some testing at my last place of employment. Destructive testing of cabling hardware. Serviced 1/2" common grade 7 strand failed at about 10k lbs. I now forget what 5/8 amon eyes deformed at, however 1/2 amon eyes deformed at benchmarks so much greater than the serviced cable that 5/8 threaded rod was therafter only employed when bracing.
My previous employer cabled alot of trees for school boards.
These two influences produced a policy that all static support systems installed by our team will be anchored with threaded rod through bolts.
We also did some testing at my last place of employment. Destructive testing of cabling hardware. Serviced 1/2" common grade 7 strand failed at about 10k lbs. I now forget what 5/8 amon eyes deformed at, however 1/2 amon eyes deformed at benchmarks so much greater than the serviced cable that 5/8 threaded rod was therafter only employed when bracing.
- Location
- Thunder Bay, Ontario
Some further reading on the issues discussed:
http://joa.isa-arbor.com/request.asp?Jou...ue=3&Type=1
http://joa.isa-arbor.com/request.asp?JournalID=1&ArticleID=3195&Type=2
http://joa.isa-arbor.com/request.asp?Jou...ue=4&Type=1
There's never enough time in a day.......
http://joa.isa-arbor.com/request.asp?Jou...ue=3&Type=1
http://joa.isa-arbor.com/request.asp?JournalID=1&ArticleID=3195&Type=2
http://joa.isa-arbor.com/request.asp?Jou...ue=4&Type=1
There's never enough time in a day.......
[ QUOTE ]
Cobra is an option, but I would figure if being installed that low, something a bit more rigid might be more beneficial. I'm very pro cobra cable, but I think this application might be a bit funny for it.
[/ QUOTE ]
I'd love to hear either you or Cobra explain the rationale for installing Cobra dynamic cabling systems?
It's my opinion that Cobra dynamic cabling systems are pure snake oil being foisted onto unwary customers by unethical arborists.
Why? Because limiting any branch's natural movement in the wind reduces that branch's ability to form reaction wood needed to stand alone without artificial support.
It's like saying that leaving a dynamically braced newly planted tree can somehow grow more reaction wood compared to an unbraced sapling.
The truth is that absent a structural fault, the branch must be exposed to the full force of the wind to put on the girth necessary to withstand the forces put upon it.
Just like a person who carries heavy loads daily will develope more muscle than a person carrying lighter loads.
That's why it's called reaction wood, it's reacting to the forces it's exposed to. The more force it's exposed to, the more reaction wood it developes. Lighten that force and you get less developed reaction wood.
I must admit that the number of CA's buying into this snake oil has shocked me. But not as much as the ISA buying into this crap!
jomoco
Cobra is an option, but I would figure if being installed that low, something a bit more rigid might be more beneficial. I'm very pro cobra cable, but I think this application might be a bit funny for it.
[/ QUOTE ]
I'd love to hear either you or Cobra explain the rationale for installing Cobra dynamic cabling systems?
It's my opinion that Cobra dynamic cabling systems are pure snake oil being foisted onto unwary customers by unethical arborists.
Why? Because limiting any branch's natural movement in the wind reduces that branch's ability to form reaction wood needed to stand alone without artificial support.
It's like saying that leaving a dynamically braced newly planted tree can somehow grow more reaction wood compared to an unbraced sapling.
The truth is that absent a structural fault, the branch must be exposed to the full force of the wind to put on the girth necessary to withstand the forces put upon it.
Just like a person who carries heavy loads daily will develope more muscle than a person carrying lighter loads.
That's why it's called reaction wood, it's reacting to the forces it's exposed to. The more force it's exposed to, the more reaction wood it developes. Lighten that force and you get less developed reaction wood.
I must admit that the number of CA's buying into this snake oil has shocked me. But not as much as the ISA buying into this crap!
jomoco
guymayor
Branched out member
- Location
- East US, Earth
[ QUOTE ]
...These two influences produced a policy that all static support systems installed by our team will be anchored with threaded rod through bolts.
[/ QUOTE ]
The broken record skips again: "No mention of through cabling with terminal fasteners like rigguy or wedgegrip?" Why make a 9/16" hole through a stem for a 1/2" bolt, when a 7/16" hole carries 15k load, i.e. a 3/8 EHS cable, with less potential stress points to fail at?
Speaking of broken records, let's ignore part #9,873 of the dynamic = snake oil rant.
Speaking of dynamic low in the trunk, I saw planetrees in Ambois France last week with 4 ton cobra low (in ~4' stems) and smaller cobra higher. They do like dynamic systems in Europe, and they seem to work.
Whatever keeps the trees in one peace is good with me.
...These two influences produced a policy that all static support systems installed by our team will be anchored with threaded rod through bolts.
[/ QUOTE ]
The broken record skips again: "No mention of through cabling with terminal fasteners like rigguy or wedgegrip?" Why make a 9/16" hole through a stem for a 1/2" bolt, when a 7/16" hole carries 15k load, i.e. a 3/8 EHS cable, with less potential stress points to fail at?
Speaking of broken records, let's ignore part #9,873 of the dynamic = snake oil rant.
Speaking of dynamic low in the trunk, I saw planetrees in Ambois France last week with 4 ton cobra low (in ~4' stems) and smaller cobra higher. They do like dynamic systems in Europe, and they seem to work.
Whatever keeps the trees in one peace is good with me.
Then please feel free to answer the question Guy.
Will a branch whose motion is artificially limited put on the same girth as an unlimited branch? How?
Please explain the rationale behind that sort of thinking Guy.
jomoco
Will a branch whose motion is artificially limited put on the same girth as an unlimited branch? How?
Please explain the rationale behind that sort of thinking Guy.
jomoco
Mangoes
Participating member
- Location
- Greater Toronto Area
[ QUOTE ]
The broken record skips again: "No mention of through cabling with terminal fasteners like rigguy or wedgegrip?" Why make a 9/16" hole through a stem for a 1/2" bolt, when a 7/16" hole carries 15k load, i.e. a 3/8 EHS cable, with less potential stress points to fail at?
[/ QUOTE ]
From JoA
Arboriculture & Urban Forestry 2011. 37(2): 67–73
Dead-end Stop Terminated Tree Support Cable Systems - E. Thomas Smiley
"Dead-end stop terminated cables provide benefits for arborists
and trees including fewer parts to stock and the elimination of the
weakest points of the traditional EHS system pointed out in an a
nonscientific survey of arborists—lag anchors and manufactured
grips. Wire Stop terminated cables inspected five years after installation
were found to have no affect on cable corrosion, cable
or branch breakage when compared to eyebolt anchored systems.
The major difference between the eyebolt anchored system and the
Wire Stop terminated system was that the Wire Stop fastened system
was associated with an enlargement in the hole drilled when
installing the cable. Thirty-nine percent of the Wire Stop terminated
cables enlarged the hole in the bark and wood around the cable.
The long term implications of hole enlargement are uncertain."
The broken record skips again: "No mention of through cabling with terminal fasteners like rigguy or wedgegrip?" Why make a 9/16" hole through a stem for a 1/2" bolt, when a 7/16" hole carries 15k load, i.e. a 3/8 EHS cable, with less potential stress points to fail at?
[/ QUOTE ]
From JoA
Arboriculture & Urban Forestry 2011. 37(2): 67–73
Dead-end Stop Terminated Tree Support Cable Systems - E. Thomas Smiley
"Dead-end stop terminated cables provide benefits for arborists
and trees including fewer parts to stock and the elimination of the
weakest points of the traditional EHS system pointed out in an a
nonscientific survey of arborists—lag anchors and manufactured
grips. Wire Stop terminated cables inspected five years after installation
were found to have no affect on cable corrosion, cable
or branch breakage when compared to eyebolt anchored systems.
The major difference between the eyebolt anchored system and the
Wire Stop terminated system was that the Wire Stop fastened system
was associated with an enlargement in the hole drilled when
installing the cable. Thirty-nine percent of the Wire Stop terminated
cables enlarged the hole in the bark and wood around the cable.
The long term implications of hole enlargement are uncertain."
Excellent observation Mango, and we all know that fresh bleeding wounds attract insects at certain times of the year, don't we?
The lateral movements that cause the egging out of the cabling holes with Rigguy and Wedge grip terminations, are isolated to the thimble and eyebolt using traditional cabling systems, allowing the entrance and exit holes to callous over and seal themselves.
jomoco
The lateral movements that cause the egging out of the cabling holes with Rigguy and Wedge grip terminations, are isolated to the thimble and eyebolt using traditional cabling systems, allowing the entrance and exit holes to callous over and seal themselves.
jomoco
Its seems that you lack a basic understanding of auxin-mediated reaction wood, thigmomorphogensis and creation of wood in trees. Wood is not formed simply by the movement of the trunk or branch.
As for dynamic vs. static cables, whether you install steel or Cobra, as a static cable, the intention is to prevent movement apart, not rotational movment within the trunk or movement side to side, or towards the other cabled trunk. Movement may be slight (measured in fractions of a mm) but sufficient to induce thigmomorphogensis. If we think about a tree swaying and examine the movement within the wood we will see that compresion and tension movement is very small at any one location but the cumulative affect allows for what appears to be large swings at the tips. The modulus of elasticity cannot be surpassed without deformation.
As for dynamic vs. static cables, whether you install steel or Cobra, as a static cable, the intention is to prevent movement apart, not rotational movment within the trunk or movement side to side, or towards the other cabled trunk. Movement may be slight (measured in fractions of a mm) but sufficient to induce thigmomorphogensis. If we think about a tree swaying and examine the movement within the wood we will see that compresion and tension movement is very small at any one location but the cumulative affect allows for what appears to be large swings at the tips. The modulus of elasticity cannot be surpassed without deformation.
[ QUOTE ]
Its seems that you lack a basic understanding of auxin-mediated reaction wood, thigmomorphogensis and creation of wood in trees. Wood is not formed simply by the movement of the trunk or branch.
[/ QUOTE ]
Then why does a sapling grown in a wind protected area put on less girth than a sapling grown in a wind exposed area?
Why do crossing branches put on more girth beyond the crossover point than below it? This is so evident in species like Brazilian peppers that have hundreds of crossovers.
Cabling a tree that does not have a structural fault may put money in your pocket, but it does no good for either the tree or your client, in my opinion.
As for synthetic support versus steel support? I'll take steel every time because it's considerably tougher than any synthetic in terms of its resistance to chewing animals, UV degradation, fire, abrasion, etc.
I have steel cabling installations that are well over twenty years old that are holding up just fine in dozens of trees throughout San Diego county.
You guys sorta crack me up promoting synthetic cabling over steel, just because it's faster to install and puts more money in your pocket quicker.
Never mind what's best for the tree or your client in the long term, right?
jomoco
Its seems that you lack a basic understanding of auxin-mediated reaction wood, thigmomorphogensis and creation of wood in trees. Wood is not formed simply by the movement of the trunk or branch.
[/ QUOTE ]
Then why does a sapling grown in a wind protected area put on less girth than a sapling grown in a wind exposed area?
Why do crossing branches put on more girth beyond the crossover point than below it? This is so evident in species like Brazilian peppers that have hundreds of crossovers.
Cabling a tree that does not have a structural fault may put money in your pocket, but it does no good for either the tree or your client, in my opinion.
As for synthetic support versus steel support? I'll take steel every time because it's considerably tougher than any synthetic in terms of its resistance to chewing animals, UV degradation, fire, abrasion, etc.
I have steel cabling installations that are well over twenty years old that are holding up just fine in dozens of trees throughout San Diego county.
You guys sorta crack me up promoting synthetic cabling over steel, just because it's faster to install and puts more money in your pocket quicker.
Never mind what's best for the tree or your client in the long term, right?
jomoco
[ QUOTE ]
[ QUOTE ]
Its seems that you lack a basic understanding of auxin-mediated reaction wood, thigmomorphogensis and creation of wood in trees. Wood is not formed simply by the movement of the trunk or branch.
[/ QUOTE ]
Then why does a sapling grown in a wind protected area put on less girth than a sapling grown in a wind exposed area?
Why do crossing branches put on more girth beyond the crossover point than below it? This is so evident in species like Brazilian peppers that have hundreds of crossovers.
Cabling a tree that does not have a structural fault may put money in your pocket, but it does no good for either the tree or your client, in my opinion.
As for synthetic support versus steel support? I'll take steel every time because it's considerably tougher than any synthetic in terms of its resistance to chewing animals, UV degradation, fire, abrasion, etc.
I have steel cabling installations that are well over twenty years old that are holding up just fine in dozens of trees throughout San Diego county.
You guys sorta crack me up promoting synthetic cabling over steel, just because it's faster to install and puts more money in your pocket quicker.
Never mind what's best for the tree or your client in the long term, right?
jomoco
[/ QUOTE ]
Point proven, you have absolutley no knowledge of tree biology.
[ QUOTE ]
Its seems that you lack a basic understanding of auxin-mediated reaction wood, thigmomorphogensis and creation of wood in trees. Wood is not formed simply by the movement of the trunk or branch.
[/ QUOTE ]
Then why does a sapling grown in a wind protected area put on less girth than a sapling grown in a wind exposed area?
Why do crossing branches put on more girth beyond the crossover point than below it? This is so evident in species like Brazilian peppers that have hundreds of crossovers.
Cabling a tree that does not have a structural fault may put money in your pocket, but it does no good for either the tree or your client, in my opinion.
As for synthetic support versus steel support? I'll take steel every time because it's considerably tougher than any synthetic in terms of its resistance to chewing animals, UV degradation, fire, abrasion, etc.
I have steel cabling installations that are well over twenty years old that are holding up just fine in dozens of trees throughout San Diego county.
You guys sorta crack me up promoting synthetic cabling over steel, just because it's faster to install and puts more money in your pocket quicker.
Never mind what's best for the tree or your client in the long term, right?
jomoco
[/ QUOTE ]
Point proven, you have absolutley no knowledge of tree biology.
Rather than backing your position with logic, examples or well reasoned debate, you choose to respond with meaningless blanket assumptions.
I expected more from you Mister.
jomoco
I expected more from you Mister.
jomoco
Try these
http://scholar.google.ca/scholar?hl=en&as_sdt=0,5&q=thigmomorphogenesis
http://scholar.google.ca/scholar?hl=en&a...C5&as_sdtp=
http://scholar.google.ca/scholar?hl=en&as_sdt=0,5&q=thigmomorphogenesis
http://scholar.google.ca/scholar?hl=en&a...C5&as_sdtp=
