Replacing Old Cable Bracing

[Whalleyrange]

There is an old Oak tree that was struck by lighting, over 18 years ago or so i am told, and was split in two.

 

It was condemned by the first Arborist who was called out to look at it.

 

But as it was in the middle of a lawn, with no potential targets and a very limited foot traffic underneath a second opinion was asked. This led to the installation of cable bracing.

 

The client who i have done work for before asked me to come and remove a few pieces of deadwood and a few low branches from a selection of trees on his property, the Slit oak being one.

 

During this procedure i had a closer look at the bracing present, and noticed pretty significant corrosion, and as the cable is under considerable tension i felt that this needed addressing.

 

I advised the client and he agreed for me to carry this out.

 

never carried out bracing on a damaged tree like this and was wondering wither i should replace with steel bracing or the cobra/boa style as it is holding the two half's of the tree together.

 

The current bracing is just over half way up the height of the tree.

It has been wrapped around the stems with blocks between the cable and tree but the blocks have all but disintegrated and the cable has become enveloped by the tree.

 

In the last picture you can just make out the current bracing.

 

Any help would be much appreciated.

 

Thanks

[Shane]

With limited risk of liability issues re-bracing would seem sensible on the assumption the decay at the base isn't too bad.

The use of cobra and the like would be an option. They have different capacities so with something of that size go for the heavy duty kit.

 

I would instal the cobra kit, maybe one 1/3 of the way up and maybe another one further above that.

 

The other issue is to get the tension right BEFORE removing the old stuff.

Any of the old bracing which has been absorbed by the tree may be better off left inside it and just remove what you can.

 

Good to see the tree given another chance - fun job!

 

Some others on here may have better ideas but that my two penneth.

Edited October 8, 2012 by Shane

[Le Sanglier]

Alright, it's Monday afternoon and I am a bit bored so I will give my opinion.

1;That looks like two trees that have grown together, not one that has been struck by lightening.

2; When you fit the cobra bracing do not under any circumstances cut what is already there, the result may well be a free ride to the hospital/morgue.

3; Give them both a light reduction to lessen the weight.

Like Shane said that's only my opinion.

[Whalleyrange]

Thanks

 

That's what i concluded for my little experience and through reading the cobra bracing literature, nice to have it confirmed.

 

So two times the 4ton cobra? as cant seem to find the 8ton rope by the meter only in the kits and as i want to add it as a static system i wont be in need of the expanding inserts or the shock absorbers.

 

I was told that they witnessed the tree being struck by lighting and that it seemed to travel along the floor and up through the tree!

 

and just leave the old bracing up there, always another little job to remove it when it does give in.

 

Should i add tension to the cobra bracing by winching the tree together and then slowly releasing it?

[gibbon]

What ever you do don't remove the old bracing.

[Czlowiek Drzewo]

That tree/ trees is ready for epic failure.

 

Is cable and bracing a good long term solution? I think that that tree will fail no matter what and cable and bracing might be wasted funds. Fell and re-plant is what i would recommend as this tree does not have much of a future.

Edited October 8, 2012 by Czlowiek Drzewo

[Whalleyrange]

its in the middle of a lawn. it doesn't matter if it fails 20 years or even 5 years down the line.

 

Old trees and dead wood are important habitat.

 

There is alot of reaction wood forming on the leaning side and the decay surprisingly not to extensive in the large wound. the tree is coping well with its injury and is in good health

 

And the client wishes to keep the tree. In the end all trees will fail, it was condemned 18 years ago and is still going strong no reason why it wont last that again.

[Wolfie]

Here's my opinion for what it's worth: give both halves a crown reduction and monitor the decay at the base of the tree.

Regarding Cobra bracing, I was under the impression that this bracing method was not designed to support the full weight of a defective crown although i would think that 2x 4T braces most likely would in this case. I would consider installing a new non-invasive wire brace.

[Bearded Munch]

We had a problem this week with an oak that was braced 12-15 years ago, at the time it was splitting open on two limbs we braced it to help retain the tree, but the rot got in and a big chunk fell off, the rest of the tree now has the grim reaper on the way.

[treeseer]

Agree with new cable and pruning; i would use steel.

 

We mortals cannot guess teh future for that tree, and risk being liars if we try.