cabling or bracing

[Chris Francis]

Cable, bracing, steel, Cobra ???

Cobra or steel cable, the tree still needs brace rods. There seems tobe an argument here about whether to cable the tree or brace the tree, but they are typically used together: cabling and bracing. And that is right out of the ANSI Standards; if you don't have the Standards and BMP's, stop! Get them. They will tell you everything you need to know, plus the standards are a much better defense than an Internet forum. You don't want to be sitting on the stand saying, "TreeGuy179 told me this would work."

The books will tell you what sizes to use, how many rods, placement of rods and cables (you pick the brand or type). It was also mentioned that through bracing should be used instead of lag threaded rod, but you can use lag threaded rod for through bracing and get the added support, but it is much more work to do it that way.

Get the books. Do what they say!

 

[TreeGuyHR]

I have installed several static cable and brace arrangements in large ponderosa pines, Douglas-firs, and a big leaf maple in situations where there was included bark and co-dominant stems; I also cabled a large oak limb to the main trunk of a tree recently just before we had a major ice storm. That limb (40 ft. long and a foot in diameter) would have most likely snapped and landed in the street if I had not cabled it! The homeowner said that the tips were just a few feet off the street (instead of 15 ft.).

The big Doug fir I cabled and braced had a subordinate trunk with chronic resin flow at the union; even though I thought it's failure potential was moderate, the target had extremely heavy traffic. The upper main trunk had several old and new ring shake cracks; maybe it wasn't by the book, but I installed three through bolted braces spaced along around 15 ft. of trunk (at different angles) there as well. This was a 120 ft. tree that had been topped, was huge (4 ft. dbh) and next to a golf course club-house. We first thinned and dead-wooded the crown, and shortened some limbs over the roof.

For braces in all big trees, I use 7/8 galvanized threaded rod and galvanized nuts and washers, and round off the thread on the stub of the rod; I sometimes have stacked two washers and two nuts on each end as well. Bomber is better in my book. After burning up lots of saw-saw blades, I bought a very expensive (and heavy!) EHS cable by-pass snipper with 3 ft. handles as well as grinder to cut the rod.

For cabling, I solely use 3/8 EHS cable, dead end grips, thimbles, and either eyed through bolts or sections of rod, also through bolted and with Amon eye nuts for anchors. I have yet to use a lag for an anchor.

I DO NOT cable and brace trees with significant decay anywhere near where I am drilling -- I believe that this is asking for trouble.

It is about time I go back and inspect all my jobs; whether or not that was in the original contract, I believe that an inspection behooves the arborist -- if the tree fails AFTER you "improved it", look out. :help:

How many of you have seen "systems" made up of soft cable bent directly around an eye, instead of at least going through a thimble? I have some samples of "cabling" in a black locust that failed two different ways in the same tree: at one point, the lag pulled out -- a loop of cable was present hanging in the air, and there was a hole in the trunk where the lag had been; in another spot, the cable had worn through and broken (and almost broke at the the end -- no thimble). :bang:

I got a call on that tree because it was making "weird noises" ---two large trunks were rubbing and creaking across an active basal crack in a slight breeze; the driveway, car, and home as the targets! :msp_ohmy: I went home, and came back and climbed up and installed truck strap tie-downs and chains at three levels along the two trunks as it was getting dark, and referred the take-down to a guy with a lift truck the next day. The guy just undid my rigging as he chunked the tree down.

The crack looked fresh, but the cabling looked like it had failed some time earlier, which made the situation even more spooky :msp_scared:. There had not been a storm, and it was mid-summer; had the extra growth since the cable failure (there were two) and summer winds done it, had the decay been a factor, or what? The home=owners didn't even know tat the tree had been cabled or was in active failure, just "making weird noises". Ever hear Click and Clack on the radio? She made the noises for me on the phone :msp_tongue:

I did not attempt to install a cable and brace system on the tree because there was decay in the butt as well as the active failure, and I had not done many installations up to that point. Possibly the tree could have been saved (three trunks, 18 in. to 24 in. each, and around 90 ft. tall), but it sure made a big pile of nice firewood!

 

[Pelorus]

You can count me on the side of the steel cable advocates if a poll is taken.
I'm gonna take a pic of a rather smallish tree that was Cobra cabled. Looks pretty ugly, like the poor tree is being held together with a bungee cord. At least steel looks professional (you have to look hard to see it) and lasts and lasts without the need and concern for periodic inspection and adjustment.

 

[TreeGuyHR]

You can count me on the side of the steel cable advocates if a poll is taken.
I'm gonna take a pic of a rather smallish tree that was Cobra cabled. Looks pretty ugly, like the poor tree is being held together with a bungee cord. At least steel looks professional (you have to look hard to see it) and lasts and lasts without the need and concern for periodic inspection and adjustment.

IMHO, the Cobra system is a good idea for a healthy tree with weak geometry or internal decay but not actual failure. The idea that a tree needs "sway" in order to lay down reaction wood to strengthen it is sound and with a basis in studies that have been done.

Drilling into cavities or internal decay columns for anchoring a fixed system is just dumb, for reasons we all know about.

OTH, I have seen a Cobra system put into a walnut that had a leader fail, in that it split for several feet at a narrow crotch -- and then a Cobra system was put in, almost closing the split. What was the point of that? The split will keep "breathing", preventing wood from being laid over the break, and decay will set in. Pointless.

 

[Toddppm]

Cobra or steel cable, the tree still needs brace rods. There seems tobe an argument here about whether to cable the tree or brace the tree, but they are typically used together: cabling and bracing. And that is right out of the ANSI Standards; if you don't have the Standards and BMP's, stop! Get them. They will tell you everything you need to know, plus the standards are a much better defense than an Internet forum. You don't want to be sitting on the stand saying, "TreeGuy179 told me this would work."

The books will tell you what sizes to use, how many rods, placement of rods and cables (you pick the brand or type). It was also mentioned that through bracing should be used instead of lag threaded rod, but you can use lag threaded rod for through bracing and get the added support, but it is much more work to do it that way.

Get the books. Do what they say!

Time to get some more link exposure eh :msp_sneaky: Dug up this and a couple other 5yr. old threads!

 

[Pelorus]

IMHO, the Cobra system is a good idea for a healthy tree with weak geometry or internal decay but not actual failure. The idea that a tree needs "sway" in order to lay down reaction wood to strengthen it is sound and with a basis in studies that have been done.

Drilling into cavities or internal decay columns for anchoring a fixed system is just dumb, for reasons we all know about.

OTH, I have seen a Cobra system put into a walnut that had a leader fail, in that it split for several feet at a narrow crotch -- and then a Cobra system was put in, almost closing the split. What was the point of that? The split will keep "breathing", preventing wood from being laid over the break, and decay will set in. Pointless.

I think in most cases the reaction wood is already present and well established before cabling is ever contemplated. The cable is just gonna act like an artificial branch union; the limb or lead above the cable is still gonna "sway"
And as far as drilling into cavities or internal decay columns, we are talking about a single 11/16 (or whatever) hole. Not exactly a big deal. Shigo's studies on the bad practice of installing drain tubes to dry out bacterial wetwood /; slime flux is completely different. A hole drilled through a stem ain't likely to alter the 02 or pH levels, imo.

 

[Jed1124]

Follow the BMP's and I'd recommend brace rods at the crotch and cable the sucker up.

+1

 

[pdqdl]

All posts concerning cabling a tree seem to cause conflict from the widely divergent opinions on the topic. I will stay out of that fray...

Here is a suggestion that never seems to appear, although I think it should be done on ALL cable-jobs: graft/splice some small branches together from the co-dominant stems.

If you take some small branches and either weave or actually graft them together in a location that will strengthen the weak crotch, you will be creating a reinforcement to the tree that is dynamic (growing with the tree) and static (it will eventually make the crotch rather rigid). Furthermore, unlike all other man-made cabling materials, it will continue to grow and get stronger with age. As a side note, there would not be much liability for it's failure, either.

Every now and then, I come across some tree that has a natural graft that spans some hideously weak crotch. So far, I have never seen one fail. I don't get many calls for cabling, but I intend to do some grafting on the next one that comes along, in addition to whatever other preservation efforts I might install.

 

[Chris Francis]

All cabling and all bracing requires periodic inspection

You can count me on the side of the steel cable advocates if a poll is taken.
I'm gonna take a pic of a rather smallish tree that was Cobra cabled. Looks pretty ugly, like the poor tree is being held together with a bungee cord. At least steel looks professional (you have to look hard to see it) and lasts and lasts without the need and concern for periodic inspection and adjustment.

I can not agre with that last statement. All cables and all braces need periodic inspection. This is true. This is wise. This can save your butt. And this is the ANSI Standard. If your client is not willing to pay for periodic inspections (yearly, preferably), you should not be installing the system. This is also a great way to (1.) make s few bucks doing an inspection, (2.) stay in your client's good graces, and (3.) possibly sell some more work.

 

[Chris Francis]

Link exposure

Time to get some more link exposure eh :msp_sneaky: Dug up this and a couple other 5yr. old threads!

Not trying to get into an argument here; I have seen things go south pretty quickly over little bits. Quite simply, I was using the search function to look for some things, and I stumbled across multiple threads that looked interesting. I didn't realize they were close to expiration or that it mattered; the material still has the same relevance today as it did when it was written. Besides, if you were talking about the link to my company website, it has been removed from my signature; I had not realized it was in violation of the site's rules. Your comment deserved an explanation. If you wish to discuss further, please PM me.

 

[jefflovstrom]

Not trying to get into an argument here; I have seen things go south pretty quickly over little bits. Quite simply, I was using the search function to look for some things, and I stumbled across multiple threads that looked interesting. I didn't realize they were close to expiration or that it mattered; the material still has the same relevance today as it did when it was written. Besides, if you were talking about the link to my company website, it has been removed from my signature; I had not realized it was in violation of the site's rules. Your comment deserved an explanation. If you wish to discuss further, please PM me.

It's all good, Todd just jumps the gun sometimes,,,,,me too,,,,I see nothing wrong with bring up old threads.
Jeff

 

[Toddppm]

Huh? Yo kmclasn I'll show you jumpin:taped: :hmm3grin2orange:

Sorry, I don't care enough to respond by PM.

 

[Pelorus]

I can not agre with that last statement. All cables and all braces need periodic inspection. This is true. This is wise. This can save your butt. And this is the ANSI Standard. If your client is not willing to pay for periodic inspections (yearly, preferably), you should not be installing the system. This is also a great way to (1.) make s few bucks doing an inspection, (2.) stay in your client's good graces, and (3.) possibly sell some more work.

I guess that Every Last One of your client's trees need periodic inspection whether they have been cabled or not! A way to skim more dough out of his coffers. However, your client today, may not be your client tomorrow, for whatever reason. A neglected Cobra system is an accident waiting to happen, imo, whereas neglected steel cable installations just seem to last, and last, and last. Eyebolts get swallowed up, but at least the tree doesn't get strangled.

 

[Chris Francis]

Tree inspections

I guess that Every Last One of your client's trees need periodic inspection whether they have been cabled or not! A way to skim more dough out of his coffers. However, your client today, may not be your client tomorrow, for whatever reason. A neglected Cobra system is an accident waiting to happen, imo, whereas neglected steel cable installations just seem to last, and last, and last. Eyebolts get swallowed up, but at least the tree doesn't get strangled.

I am not sure which parts were sarcastic, but I agree that the synthetic cabling can girdle the stems, whereas the properly installed steel cables would not. However, I see old steel cable systems that have been neglected that are not doing their job anymore; trees grow, and things change. Some cables become too tight. Some cables become too loose. Some cables break. Some cables become undersized (as the tree grows). Some cables end up in the bottom half of the tree (as the tree grows). Some hardware fails. Some systems were improperly installed. And those are just the ones that come to mind that I have seen within the last month (not my installations). I have also ran across a cable that had broken out of a tree and was dangling close to the ground, where it could easily come into contact with a walker or bicyclist. So, even steel should be routinely inspected. And to answer the question:

I'm not trying to skim anything or rip anyone off. I offer a service that people can tale or leave. I'm not selling the last gallon of water in the desert or the last gallon of gas after a storm (which is a whole 'nother can of worms entirely, but for the record, if I needed something to drink or a generator, I would be willing to pay more for it and grateful that someone was there to sell it to me, but way off course here). First part, cable and brace systems need inspections and adjustments. I am not willing to do it for free. The client needs to understand up front that these systems need maintenance, like their cars do. And I want to protect my own butt by offering the inspections because the ANSI Standards say so. For the record, I do let people know that there are other arborists that can perform the inspections as well. But, probably the biggest reason to perform the inspections (and likely why ANSI is concerned with it) is because cabling/bracing is a band aid. When the systems are installed, there is a problem in the tree that warrants the installation of a supplemental support system. Trees tend to get worse in time, not better; so, the inspection might reveal severe decay or some other problem. You really can't argue with the Standards.
Second part, I wasn't talking about inspecting every tree on every customer's property. And while I think that is a great idea, I understand it is not normally possible due to time and financial constraints. I do think everyone should have at least a consultation on his/her property to discuss potential problems, things to do and not to do, etc... I am experienced in tree risk assessment, whereas many CA's are not. But even a CA has a much better understanding if trees than run-of-the-mill tree man. And the average tree guy knows more than the average home owner. So, yes, the average homeowner can do himself a
big favor by having an expert examine his trees, even if it is just briefly. And yes, I charge for that. There are guys willing to "take a look" at no cost, but those opinions are usually all OCR the map and often miss the important stuff; some of them may even be qualified to make better assessments, but time does not allow a thorough evaluation. If I have a salesman, I can't afford to have him trotting around someone's property all day giving free risk assessments, all the while increasing my liability if a failure was to occur. And if I'm doing it myself, I have the opportunity cost as I could be somewhere else making money or spending time with the family. There are only so many hours in the day!

 

[Pelorus]

No sarcasm was intended, Chris, and I am certainly not advocating for the neglect of any cabling systems. I think many of the problems you have mentioned seeing re. steel cables took a longer timespan to occur than dynamic cabling has even been around. In a shorter timespan, of say 5-10 years, a neglected Cobra patient is far more likely to suffer from the consequences of that neglect than a steel patient. Yes or no? Clients move, they die, they lose their jobs, tree companies go out of business, etc, so how do you possibly guarantee your UV-stabilized (sort of), non squirrel proof, dynamic cables (with their ingrained propensity for limb strangulation) are gonna receive the care and feeding they crave?
Do you get the client sign a disclaimer waiving you of responsibility?

 

[Chris Francis]

Cabling and bracing needs inspection by a qualified arborist

No sarcasm was intended, Chris, and I am certainly not advocating for the neglect of any cabling systems. I think many of the problems you have mentioned seeing re. steel cables took a longer timespan to occur than dynamic cabling has even been around. In a shorter timespan, of say 5-10 years, a neglected Cobra patient is far more likely to suffer from the consequences of that neglect than a steel patient. Yes or no? Clients move, they die, they lose their jobs, tree companies go out of business, etc, so how do you possibly guarantee your UV-stabilized (sort of), non squirrel proof, dynamic cables (with their ingrained propensity for limb strangulation) are gonna receive the care and feeding they crave?
Do you get the client sign a disclaimer waiving you of responsibility?

I feel ya. All of those things do happen (people move, tree co. goes out of business, etc...), and I do feel more comfortable with the steel. However, a properly installed synthetic system would likely last and self-adjust for 5-10 years. All of the horror stories and photos of synthetic cabling I have seen involved (1.) improper installation (placement well below the 2/3 distance from the crotch) and (2.) neglect (no inspections or adjustment). To answer those questions, let me start by saying that I have never used a synthetic system; I am a steel guy myself (cable and brace whenever possible). But, the synthetic stuff is now in the ANSI, so I would use it if the application fit. I do have our customers sign our Terms & Conditions, but it is broad in scope. I have a few blank lines where additional notes can be added, such as "Your cable/brace system requires annual inspection, etc..." But I don't think you can ever sign away all of your liability, otherwise doctors would do it and never get sued.

My main point I was trying to add to this thread was that brace rods should be considered along with the cabling (of choice, for argument's sake). The question and argument seemed to be: "Which is better, cable or braces?" That is the wrong question. If you want to use synthetic systems for cabling, don't forget the tree could still benefit from brace rods, which are, by the way, much more invasive than drilling a little hole for a steel cable attachment, but the trees seem to adapt. I don't really buy the synthetic argument of "this is so much better because it saves the tree from drilled holes." The little holes drilled for the cables go virtually unnoticed; and no, it is not a good idea to drill into a rotten spot, but it is also not a good idea to attach a rope to a rotten spot either.

 

[Sunrise Guy]

In these litigious times, I leave cabling to others. All of my cabling gear sits in a plastic tub, in my garage. If a tree needs to be cabled, in the mind of a client, I will explain all of the various liability issues, and then either do a take-down or give a polite, "Thanks, but I'm going to need to let this gig go." I know that cabling has been used effectively on many historically significant trees and less "important" trees that homeowners can't bear to lose, but I can't understand why you would want to expose yourself to the liability issues, waivers or no waivers. Keep in mind that in the event of significant damage and/or fatalities due to a cabled leader failure, that you worked on, you will be gone after, waiver or not. A good lawyer goes after even those who are "sure" they have protected themselves, legally. Read up on cases where waivers failed to protect the parties who drew them up. You cannot protect yourself against work that is determined to be shoddy, even with a waiver, and since shoddy is in the eye/mind of the (legal) beholder, you may be in for some real grief, financial or otherwise, once the court system gets done with you.

 

[Chris Francis]

lawsuits and trees

In these litigious times, I leave cabling to others. All of my cabling gear sits in a plastic tub, in my garage. If a tree needs to be cabled, in the mind of a client, I will explain all of the various liability issues, and then either do a take-down or give a polite, "Thanks, but I'm going to need to let this gig go." I know that cabling has been used effectively on many historically significant trees and less "important" trees that homeowners can't bear to lose, but I can't understand why you would want to expose yourself to the liability issues, waivers or no waivers. Keep in mind that in the event of significant damage and/or fatalities due to a cabled leader failure, that you worked on, you will be gone after, waiver or not. A good lawyer goes after even those who are "sure" they have protected themselves, legally. Read up on cases where waivers failed to protect the parties who drew them up. You cannot protect yourself against work that is determined to be shoddy, even with a waiver, and since shoddy is in the eye/mind of the (legal) beholder, you may be in for some real grief, financial or otherwise, once the court system gets done with you.

I can't really argue with that. People will sue over anything. The best thing you can do is follow the standards to the letter. When we cable/brace, we measure and document everything, and if there are any variations we record them and the reason why. I have not had any problems with hardware, but it is bound to happen. Here's a little story though. We planted some large plants for a customer (lawyer, of all professions). I know they were planted correctly because I took part inplanting them and checked every one. Anyways, I get a nasty letter in the mail with pictures of a dead camellia, including one focused on the root ball and the bottom half of the wire basket that was left on the plant. This had a large arrow drawn pointing to it and was referenced in the letter something to the effect of: "Is this the way that you plant your plants? No wonder it died!" I was excited to reply. The client never called to say the plant looked funny, turned brown, or anything else. Chances are it was under watered or over watered, but I never got a chance to look at it and see. If there was any doubt we screwed up, I would have replaced the plant at no charge just to avoid the confrontation or the possible bad PR, but when I got a nasty letter pointing fingers, blaming me, and insulting my intelligence, I had to fire back. My letter included references to the ANSI A300 Standards and the ISA Best Management Practices for Transplanting. My response was: "Yes, this is EXACTLY how we plant our trees, according to the standards and BMP's." I explained in detail the reasons why and that there is no better way than the standards. I never heard from him again. If I had tried to do something a new or better way or the way Grandpa did, my butt would have been nailed to the wall.

 

[TreeGuyHR]

I think in most cases the reaction wood is already present and well established before cabling is ever contemplated. The cable is just gonna act like an artificial branch union; the limb or lead above the cable is still gonna "sway"
And as far as drilling into cavities or internal decay columns, we are talking about a single 11/16 (or whatever) hole. Not exactly a big deal. Shigo's studies on the bad practice of installing drain tubes to dry out bacterial wetwood /; slime flux is completely different. A hole drilled through a stem ain't likely to alter the 02 or pH levels, imo.

I usually through-bolt my anchors with either half inch eyed bots or a section of 5/8 or 78 threaded rod, also through bolted. I am leery about using a lag unless it is a hardwood and i know it is sound.

I do worry that a stem with advanced decay would be weakened with a 1 in. diameter hole to install a heavy through bolt; I suppose if the rind was at least 30 -50 % it might be OK; I would prefer to pick a spot with no decay if possible, even if the placement is not ideal (not quite at the right place to meet the 2/3 rule for placement along a large limb or sub-trunk).

I have probably installed 15 cable and brace or cable only systems over 5 years, and none have failed. I have observed around 10 that were either incorrectly installed or had broken -- even on the US Capitol grounds in Washington D.C.!