V.T.A symptoms "the chatty trees"

[RobRainford]

 

No:lol:

 

The way it reads I thought it was!

[Treecreeper1961]

Is it just me or does an increased knowledge of V.T.A. lead to a view of trees that can become complex at times?

There has been much said here and else where regarding compression forks, included bark and species prone to such characteristics and their potential failure. Most of us are well aware of these things now but being able to recognise the language is just the beginning. Full translation is something else, if you know what I mean.

 

Sometimes it seems like every beech tree I look at has a compression fork or some kind of included bark complication.

1 How do we go about making a sensible assessment of these trees without a knee jerk reaction?

As has been said on this thread, it is not a question of if but of when will these conspicuous unions fail.

2 Well, if that is the case, what about the 80ft beech with multiple potential failure points situated in a high risk zone?

A fine tree perhaps, still growing, with no signs of disease or decay, which has already withstood the test of some considerable time.

3 What if this tree is multi-stemmed? Too large by far to attempt formative pruning. If removal or reduction of stems is considered as a preventative measure what about the resulting decay and dysfunction?

4 And how do we predict which of the stems are most at risk of failure?

 

 

Experience I hear you say! Of course. So far, my experience has shown me that such chatterings are prone to sudden and, as far as the timing is concerned, difficult to predict failure.

The conflict I have in my mind is one I guess most are familiar with when they are relatively young in their V.T.A. lives, it's a judgement call and one that may be very unpopular and take many years to be proven as one that should have been made.

 

I have got some photos below, not trees that I am responsible for, but do have connections with, and any comments would be appreciated.

[Tony Croft aka hamadryad]

Is it just me or does an increased knowledge of V.T.A. lead to a view of trees that can become complex at times?

There has been much said here and else where regarding compression forks, included bark and species prone to such characteristics and their potential failure. Most of us are well aware of these things now but being able to recognise the language is just the beginning. Full translation is something else, if you know what I mean.

 

Sometimes it seems like every beech tree I look at has a compression fork or some kind of included bark complication.

1 How do we go about making a sensible assessment of these trees without a knee jerk reaction?

As has been said on this thread, it is not a question of if but of when will these conspicuous unions fail.

2 Well, if that is the case, what about the 80ft beech with multiple potential failure points situated in a high risk zone?

A fine tree perhaps, still growing, with no signs of disease or decay, which has already withstood the test of some considerable time.

3 What if this tree is multi-stemmed? Too large by far to attempt formative pruning. If removal or reduction of stems is considered as a preventative measure what about the resulting decay and dysfunction?

4 And how do we predict which of the stems are most at risk of failure?

 

 

Experience I hear you say! Of course. So far, my experience has shown me that such chatterings are prone to sudden and, as far as the timing is concerned, difficult to predict failure.

The conflict I have in my mind is one I guess most are familiar with when they are relatively young in their V.T.A. lives, it's a judgement call and one that may be very unpopular and take many years to be proven as one that should have been made.

 

I have got some photos below, not trees that I am responsible for, but do have connections with, and any comments would be appreciated.

 

I am currently experiencing issues with my screen which appears to be intermitent, so reading and seeing images is a problem at the moment. i will come back to this and answer fully as soon as I can.

 

A good post and subject that really does need a lot of discussion. I dont think they ALWAYS fail just that it is the weak point and MOSTLY it proves to be a weak link in the biomechanical chain.

 

One thing I will say here is that no matter how big a tree is, crown modifications are possible on all our natives, and it is not to be overlooked as a method for adressing structural faults or managing old age in our tree stock. felling is the last resort, and IME the last resort is usualy a rare thing.

[treeseer]

One thing I will say here is that no matter how big a tree is, crown modifications are possible on all our natives, and it is not to be overlooked as a method for adressing structural faults or managing old age in our tree stock. felling is the last resort, and IME the last resort is usualy a rare thing.

 

The funny thing is, cabling to mitigate these bad unions seems to be rarer yet in UK, but why?!

 

Low cost, low invasiveness, high effectiveness.

 

The attached cable job <2 hours, <100 pounds worth of material. tree is 80%+ hollow; has a pretty shroom at the base, nice.

Cable--Thoburn Oak DB AA.pdf

[davyjones]

Just how many years previous did the appraisal get done?

 

Ganoderma australe could more than likely not even fruited yet in such a scenario, so would be difficult to say the appraisal was bad, unless there was a perenial bracket with its annual layers available for the count.

 

G. australe can be a difficult one to detect sometimes all thats there (like Kretzschmaria deusta) is a small hard blackened bulb low at the butress bases.

 

Given the low level of info avaliable on G. australe, and the none existent understanding of panic fruiting as described by Gerrit Keizer its no surprise such a tree was under evaluated.

 

You're quite right, and I wasn't judging the previous appraisal, as I have not been provided with a copy (I cringe at some of the 'accepted wisdom' I used to spout forth so who am I to criticise?).

 

I have somehow lost/mislaid the other images I took when I visited this site .

 

There is a large perennial bracket (also G australe) at the base of this tree which has ceased to produce incremental growth (approx 3 years of annual layers of decreasing size). The stem is pretty hollow and the in-rolled bark at both sides of the compression fork and in both stems, with cracking extending into the stem were pretty apparent post-failure.

[treeseer]

...this tree which has ceased to produce incremental growth (approx 3 years of annual layers of decreasing size). .

 

Sounds like it did still produce growth; just less growth. just saying.

 

Great pix, thanks!

[Treecreeper1961]

The funny thing is, cabling to mitigate these bad unions seems to be rarer yet in UK, but why?!

 

Low cost, low invasiveness, high effectiveness.

 

The attached cable job <2 hours, <100 pounds worth of material. tree is 80%+ hollow; has a pretty shroom at the base, nice.

 

Sorry Treeseer, I am not sure if I have missed something here? Can't see an attached cable job in the attachment, but an Arbor Age article on the subject along with an interesting case of the Thoburn Oak.

Don't suppose you can post up the next edition of the mag. to see what the 'Arbor Master' has concluded?

I'm guessing it involves cable bracing judging by the red line in the picture. The angles involved seem to give fairly limited support, what do you reckon?

[treeseer]

Sorry; forgot that the AA piece was a 2 parter and i lack a pdf for the 2nd part.

 

Yes the 3/8" EHS cable went in at the red line. Support there is not too limited--more than a foot of good holding wood at each end, where the cable is held by wirestops as shown in the opening pic.

 

Compared to pruning off benefits, support is a very conservative solution to almost all the trees seen in this thread. Like hama I truly enjoy reshaping a tree to prepare it for the long haul, but for the worst defects a slender strand of steel can help retain a lot of crown, and avoid a lot of pruning wounds.

 

THOBURN OAK OBSERVATIONS AND DISCUSSION

Nine feet above ground, the trunk forked into four scaffold limbs. Three years ago, one limb failed and was cut back to the trunk. A new branch is growing next to the stub. The limb growing to the northwest is declining; many of its small laterals and twigs are leafless. Below this limb there is decay in the outer trunk at ground level, 30 inches wide, facing the sidewalk. Resistograph readings showed that the decay is only 1-2” deep, but probably deep enough to prevent good uptake of any injected material. The sidewalk meanders slightly around the trunk. The panels near the tree appear newer, and the edges of some have been ground down, apparently in response to upheaval by expanding roots.

 

A palm tree growing in the cavity was pulled out easily, because the roots stopped where a 3” layer of concrete was installed to “cap” the cavity. Where this concrete met the declining limb there is a thick bulge of tissue, showing that the concrete blocked the flow of sap, making the limb less healthy and less stable. The standards on tree support state that “Treatment of cavities by filling shall not be considered to provide support”4, which is one reason cavities are seldom filled today. A streak of decay extends from the cavity between the declining limb and the limb growing toward city hall. There is no crack forming, and the Resistograph again showed that the decay is only 1-2” deep, with 17” of undecayed holding wood. Pruning will reduce the considerable load on this minor defect, and adding supplemental support can prevent failure in the future.

 

Although both limbs are almost horizontal, they each have upright lateral branches that are large enough and vertical enough to hold a cable. The standards call for a 5/16” Extra High Strength cable to support limbs of this size, so a 3/8” cable would be superadequate. Drilling through both limbs and installing a brace rod could be done to add more support in the future, but the additional wounding and expense does not seem warranted now. With the cable installed, the pruning can be limited to dead, dying, and the most overextended branches. The southwest limb has little root disturbance underneath, so it has high vitality. Lightly pruning the heavy end near the wires would increase the tree’s symmetry and stability.

 

MANAGEMENT OPTIONS

Prune dead, dying, and overextended branches.

Install a 3’8” EHS cable to support the decayed fork.

Remove concrete carefully, avoiding bark damage.

Test the soil, and add nutrients that are lacking.

 

The city was satisfied, and decided to go ahead with the cabling of the municipal tree. Given this experience, it is clear that municipalities can and will accept tree cabling. According to Matheny and Clark, “Almost by definition, arborists have a responsibility to care for trees”, and that duty is not breached if we act in a reasonable manner.* Offering opinions about trees’ dignity or decrepitude without analyzing the facts is not part of a professional risk assessment.

Members of the American Society of Consulting Arborists (ASCA) follow their Standards of Professional Practice, Item 4.2 G. :* " Members shall not take advantage of their positions as Experts by assigning or implying greater significance to an interpretation than it warrants. The degree of certainty of an opinion is as important as the opinion itself and Members shall do nothing, actively or passively, to misstate the degree of certainty." 


 

Instead of reporting defensively by injecting opinions or exaggerations, we should be systematically assessing standard treatment options to abate risk. If the treatments follow the standards and the ISA BMP’s, there is no reason to fear liability from working on trees that some would dismiss as “decrepit”,

[Treecreeper1961]

Cheers for that.

 

Good outcome and great to see a veteran tree retained.

I love it, I do, but...

 

Not wanting to be negative, just making observations:

 

Cabling should be able to restrain a failed section in such an event. Don't think that the angle here would restrain much before it hit the floor.

 

There is a trend over here to use non invasive, flexible systems. Is that the case with you guys?

 

From the picture I would have said retrenchment pruning or more severe reduction than has been prescribed would have been a better option. Reducing the weight and lever arm effect. It is obvious that tree is in a vulnerable state and not going to last forever.

 

No tree lasts for ever, it is true. Trying to retain such a mature tree in such a public space is admirable but is it advisable.

 

I wish I had the guts to go with it.

Defensive advice may be wrong but it is not a clear cut, black and white scenario we are often presented with. Getting the balance right is not easy, the more cases I come across the better my judgement will become, I hope.

[Treecreeper1961]

I came across a tree exhibiting some interesting tell tale signs today, a beech again, but not a compression fork. Any ideas what is going on here?