04/06 Live Oak Project Update

[Fireaxman]

April 2006 I asked for and received a lot of good advice on a Live Oak in Madisonville, Louisiana that was damaged by Katrina
http://www.arboristsite.com/showthread.php?t=32186

I posted a follow-up on it August 2006 http://www.arboristsite.com/showthread.php?t=35900

I am pleased to report that as of June 2007 the "Dynamic Non-Invasive" cables (my first cable job) are still holding and the tree is still standing fully intact, having survived gusts to 50 mph in summer thunderstorms.

The cables are taking a very considerable load now with this year's growth and water from weekly summer rains, and the split has opened up a little more. The tree is vigorous, with fresh new growth all the way to the tips of the branches, many water sprouts, and a healthy crop of acorns. Frankly, I am surprised the cables are holding up with the added weight and the (this year) frequent summer storms.

If it makes it through the summer I wonder if some reduction might be appropriate next winter.

 

[cntrybo2]

i am new to this project. can you please give a short synopsis on what type of cable was used to make your loops and what the black material used for the cable sleeves is. just curious and i am really excited about this project for you man, WAY TO GO!!!

 

[Fireaxman]

One Last Pict

I am really pleased at how innocuous the cables and slings are. Even standing directly under the tree, I have to very deliberately point them out for most people to notice them.

 

[Fireaxman]

i am new to this project. can you please give a short synopsis on what type of cable was used to make your loops and what the black material used for the cable sleeves is. just curious and i am really excited about this project for you man, WAY TO GO!!!

I used the "TreeSave" 10/20 cable and the "Non-Invasive Support Slings" shown on page 95 of the 2006 Sherrill Catalog. I assume it is the same stuff as that shown on page 123 of the 2007 Master Catalog. The black material is the "Anti-Abrasion Cover" for the support sling. I did not need the optional self adjusting strap because I had a good strong crotch for each of my sling locations.

 

[jomoco]

Professional Cabling?

I'm not quite sure where or who you got your cabling advice from, but I'll be polite and assume it's temporary, and that you intend to do it right in the near future.

I respectfully suggest you buy a professional cabling and bracing book from a respected arborist supply house, take some time to read it well, then cable the tree properly.

Please don't take offense at my observations and sincere advice, but I've cabled hundreds of trees, and am fairly well respected for my knowledge of proper long term cabling success, particularly with old oaks.

Good luck!

jomoco

 

[Fireaxman]

... I'm not quite sure where or who you got your cabling advice from, but I'll be polite and assume it's temporary, and that you intend to do it right in the near future.

jomoco

If I were a "Professional Cabler", I probably would not be posting this as an "Arborist 101" thread. The work was a low risk volunteer project for church freinds who could not afford a professional. However, I did my homework with research on this web site and the ISA cabling best practice flier. If you have some constructive, specific advice to offer please do.

 

[jomoco]

Good cabling reference

If I were a "Professional Cabler", I probably would not be posting this as an "Arborist 101" thread. The work was a low risk volunteer project for church freinds who could not afford a professional. However, I did my homework with research on this web site and the ISA cabling best practice flier. If you have some constructive, specific advice to offer please do.

I respectfully suggest you go to the following link:

http://www.umass.edu/larp/pdf/Chaper_6_Cable_Bracing_&_Guying_Final.pdf

In a tree of that size you'll want the larger hardware and cables all galvinized.

Definitely use the drop forged eyebolts sized to go all the way through the wood with the large galvinized washers and nuts on the backside.

Good luck with your project!

jomoco

 

[cntrybo2]

i by no means am a cabler, but i think the intent for the project was to make it a non-invasive repair. This being the case, using eye-bolts would change the project totally.

 

[treeseer]

jomo, your link is the exact bmp that fireax referred to. If MAA wants to copyright something that is 5 years old I guess they can, but that does not mean it is current. Anyway, if your eminence has a moment free after patting his own back so much, please show us ignorami the place where drilling and steel is required.

Thanks for the followup, Fireax, but I do not like the growth of that crack.

 

[jomoco]

You are free to do mickey mouse cabling

jomo, your link is the exact bmp that fireax referred to. If MAA wants to copyright something that is 5 years old I guess they can, but that does not mean it is current. Anyway, if your eminence has a moment free after patting his own back so much, please show us ignorami the place where drilling and steel is required.

Thanks for the followup, Fireax, but I do not like the growth of that crack.

You guys are perfectly free to do all the mickey mouse cabling you want to, just don't delude yourself into thinking it's professional cabling, it's not.

My clients would laugh me off the job if I used those mickey mouse, cambium cutting, tree deforming, short sighted slings to support thousands of pounds of weight with, the bloody tree is splitting in half, it's in dire need of a professional, soon.

I tried to be polite about it!

jomoco

 

[Tree Machine]

hopefully helpful input

I politely have to agree on really big trees, high-tensile cable with far-side terminations will endure the tonnages of force that Mother Nature deals out.

Jomoco refers to 'cambium cutting' and that's a real threat, especially if the system is highly tensioned, as it should be in the case of a split trunk, and if the tree moves to much degree, as it will in rougher winds. Think 'aerial girdling root', only it moves when the tree moves. That's a possible concern. If your system wears on the cambium, it is no longer a 'non-invasive' system. UV radiation exposure through the years is more of a promise and time will tell how these stand up, though there is no possible way to determine degree of strength decrease while the system is installed.

I 'cabled' a tree about a decade ago with Sampson 1/2" Stable Braid, both stems were hollow so lags, or even thru-bolts were not a great option. I didn't have swaging tools to terminate cable loops around the stems, and chain was heavy. The tree was not split in the crotch, but showed the potential. It was in definite decline and the owners didn't care so much if the houseward half failed, they just wanted it secured it so the one half wouldn't whack the house, even if it did split. They also wanted inexpensive. OK, bull rope and running bowlines to terminate.

When I came back some months later and saw my Stable Braid hanging limp off one of the stems, my jaw dropped. I had to climb and see what had happened. Part way up I saw some blue fiber sticking out of a hole and it all came clear-squirrel nest!

As cool and innovative as I think the synthetic dynamic cabling systems are, they're far too expensive and involved to become nest material. Also, dynamic systems are OK to prevent splitting, but static systems are much better designs for trees already split. They need some come-along work to pull the stems together and relieve the tension in the defect, and a secure system that will hold the crown in place and prevent that splitting tension from recurring.

This is just some fact, and some personal experience shared. It is in no way meant to be a criticism. I think your efforts are to be applauded, Fireaxman. All efforts to preserve tree are lessons, and I think its great you've taken the time and effort to share with us the work you've done. You've given the client what they asked for. However, they may not have realized what it is they need.

Now Jomoco, that was polite.

 

[alanarbor]

Now Jomoco, that was polite.

Most certainly more constructive.

I have to agree with TM here. With the tree actually failing, the slings are under an enourmous amount of tension, and could actually already be in the process of crushing cambium tissue on the pressure side.

In this particular application, the use of through bolts would probably have been the best choice.

You could consider some weight reduction thinning, and possibly installing static cabling attachments. At this point it really becomes dealing with tree engineering more than tree health. To be blunt, you may have to consider some pruning that may go beyond what is generally considered to be "healthy" for the tree, in order to lessen its likelihood of failure.

However if the risk is too great to be tolerable near those structures, removal may have to be considered.

 

[Fireaxman]

... i think the intent for the project was to make it a non-invasive repair. This being the case, using eye-bolts would change the project totally.

True. I would have liked to rod the base with several good strong rods, but the Sherrill expert steered me away from that idea. Too much chance of sticking the bits in a base that thick. I considered the eye bolts and steel cables in the crown, but at the time I frankly was not comfortable enough with my climbing skills (double crotched that far apart in such a spreading canopy) to feel comfortable handling the necessary drilling. Part of my apprehension resulted when I almost ripped out the pelvic D of a Navaho V2 BOD saddle trying to traverse between the two major leads. So I pulled the limbs together with my Tirfor and installed the dynamic system.

You men have persuaded me Cables would be better, and I think my skills have improved to the point I would like to try the drilling. I'll talk to the homeowners and see if they want to let me add the hardware. I'm also thinking the steel cables might be easier to install now that I have some (temporary?) ropes in place to work around. They give me a nice clear line of sight to help me keep my holes streight.

Just a thought - Do you think it would be safe to run my Tirfor across those two major leads and use the Tirfor cable for a zip line and tie in point? Could save me a lot of Yo-Yo action. The Tirfor says "Not for Support and Lifting of Personnell", but I am thinking I could secure the Tirfor cable with clamps after I have it tentioned.

The "Dynamic System" really was very easy to install, and I guess I have to say it has actually exceeded my expectations in holding the tree together thus far. Maybe it really is "Temporary", until I can develop a better skill set and do the job right. That the crack continues to open up is a pretty good indication something more is needed, and I'll also check the slings more closely to look for cambium cutting.

Thanks, everybody, for the advice and the patience.

 

[treeseer]

Good posts by tm and alan. At last years expo, andreas detter talked on cabling and shared the number of dynamic cables documented as preyed upon by Rodenta--exactly one. Since dynamic is the standard in germany, he should know. Sorry about your rope, Jim.

I have to recable a similar-sized-and -configured live oak next week, and as much as I hate to drill, it'll be steel, the OTHER professional system.

 

[Fireaxman]

Thanks, treeseer, for the reassurance. I stopped by this afternoon and climbed the tree to get a good close look at what is happening with the dynamic cabling. The cables are not as tight as they looked from the ground. Firm, and obviously holding some weight, but not in any 9 line bind. I was able to pull a couple of the slings aside enough to get a look under them. The bark looks a little scuffed, about the way it looks after I've drug my Merrells across it a couple times, but there is no sign of damage to the cambium, no weeping, no callous, no exposed wood. The homeowner is very pleased with the work, reluctant to spring for more hardware (even with free labor), and reluctant to let me poke holes in his tree. I'm a little cramped for cash and time right now, so I guess it will have to ride for a little while. I'll keep a close eye on it. If nothing else we may all get to see what happens to "Dynamic Cabling" when tested to the extreme. Just dont judge it entirely by this. Remember it was selected and installed by an amateur.

Whatever, I am impressed with it enough to believe the stuff has a valid place in the arborist's tool box. It is incredibly light, easy to work with, and strong. Again, I do not claim to be a "Pro", but I do think the man and the equipment are a step or two ahead of Mickey. No offense intended, Walt.