Cobra Synthetic Cabling Merits?

[Marc]

There is a place for both systems, Cobra style systems should never be used on a clear weak union that has begun to fail this is clearly stated by Cobra in there literature. Much like how Picus clear state you should never fell a tree based on the results it gives.

So Cobra has a pretty good get out clause there in case of failure.

 

More thought it always needed. I have seen many steel cable installations fail usually because a lag bolt was screwed in rather than a right through and back plate. Species such as Oak and Horse Chestnut are a particular problem due to the amount of tanins I guess in the wood react with the invasive steel bolt, species like beech on the other hand will completely envelop the bolt securely in time.

 

On the flip side I have seen and worked on trees with historic good quality steel cable bracing installation. I have noticed in some cases the tree has become weak and look dependent on the brace for support in one instance on a heavy Beech lateral the cross section had become oval where the limb had put on incremental growth in the directions it could move but nothing in the support direction, I almost felt had we cut the wire the limb would fail. We carried out a reduction of the limb and installed a large steel a frame prop.

 

So neither system is perfect and both need regular inspection and adjustment.

 

As for the Cobras ability to hold a failed limb, I can honestly say if installed correctly it'll support a massive load! We condemned an Oak many years ago, but the council refused our application to fell and instead pushed reduction and brace which we did, several years later the tree failed unzippering from the bifurcation down in high winds, the cobra held it all together.

In hind sight maybe a steel static system would of been better but I still question the be fit of retaining a tree with such obvious defects in an urban environment unless it has a real value.

 

I would really like to carry out more steel cable bracing, the main issue is expense, cobra is simple and quick even the static systems to install and do work, and like all systems if the tree has a significant defect it need yearly or bi yearly inspection in reality it's cheap and quick enough to just replace every 5 years.

Again I have seen 10 year old Cobra that is still perfectly functional only it either needs adjusting or moving higher, trees are dynamic they grow so non invasive synthetic dynamic or static systems or well suited to the task or growing with the tree.

[Jake Andrews]

I have to agree with Marc. I believe there is a situation for both. Don't use cobra on unions that you don't want to move, cobra for anything else. During my time in Australia I would be cabling approx 4-5 times a month and using both steel and dynamic for different situations. I have even installed both on a single tree where I couldn't install steel high enough because of insufficient holding wood and had to place it lower than ideal. I then installed cobra higher in the canopy to counteract the whiplash effect in high winds.

 

I'm going on the AA cabling course next Saturday which should be good. I would like to no more about the British Standard and what it says. Looking forward to it.

[jomoco]

Sounds like a few of you are of the opinion that fires are not a natural component of the tree's environment!

 

Surely you jest?

 

Your honor I object!

 

Jomoco

[Rich Rule]

Fires maybe so?

 

Different environments though, I dare say the incidence of fires damaging trees is greater in California compared the the wet West coast of Wales.

[treequip]

Sounds like a few of you are of the opinion that fires are not a natural component of the tree's environment!

 

Surely you jest?

 

Your honor I object!

 

Jomoco

 

Fire? well I will give you that trees do burn but, you do know that you are talking to people largely located in the UK don't you? A place where when people go brown in the summer its likely to be rust rather than sunburn.

 

So how many cobra failures are attributed to fire damage, how many cobra failures are documented over all? Don't know?, no me neither.

 

Case dismissed

[jomoco]

You will hardly be the first lot that pay a high price for ignoring Murphy's Law.

 

The folks fleeing Fort Mac in Alberta might not agree...

 

Best increase your liability coverage if you like to gamble lads.

 

NFPA - Home Structure Fires

 

Jomoco

[treequip]

You will hardly be the first lot that pay a high price for ignoring Murphy's Law.

 

The folks fleeing Fort Mac in Alberta might not agree...

 

Best increase your liability coverage if you like to gamble lads.

 

NFPA - Home Structure Fires

 

Jomoco

 

Dude, that's very sad for those folks but where is the relevance to cobra bracing?

 

If you don't have an answer feel free to just change the subject again.

 

 

we don't live there, we are in the UK

[jomoco]

Dude, that's very sad for those folks but where is the relevance to cobra bracing?

 

If you don't have an answer feel free to just change the subject again.

 

 

we don't live there, we are in the UK

 

The relevance is that in a court of law, replacing a non-flammable tree support system with a highly flammable system?

 

Can and will be deemed as grossly negligent.

 

The professional arborist associations who've given the thumbs up on these synthetic tree supports?

 

Guilty of gross negligence as well in my professional opinion.

 

Jomoco

[jomoco]

There is a place for both systems, Cobra style systems should never be used on a clear weak union that has begun to fail this is clearly stated by Cobra in there literature. Much like how Picus clear state you should never fell a tree based on the results it gives.

 

Again I have seen 10 year old Cobra that is still perfectly functional only it either needs adjusting or moving higher, trees are dynamic they grow so non invasive synthetic dynamic or static systems or well suited to the task or growing with the tree.

 

Thanks for the feedback Marc, I appreciate it.

 

Any signs of cambial engulfment of the termination straps on those ten year old's mate?

 

Jomoco

[treequip]

The relevance is that in a court of law, replacing a non-flammable tree support system with a highly flammable system?

 

Can and will be deemed as grossly negligent.

 

The professional arborist associations who've given the thumbs up on these synthetic tree supports?

 

Guilty of gross negligence as well in my professional opinion.

 

Jomoco

 

Lets re visit this when you can cite case law, chapter and verse to back this up.