Interesting Biomechanics

[David Humphries]

I was back in the tropics this week and snapped these in a park area in Townsville, just thought it interesting that one tree had self grafted and the other...well, not quite more like resting on itself...

 

Tree species Albizia saman (monkeypod tree)

 

 

 

Interesting shots Sean.

 

 

On an aside, just picked up upon the research program at both Manchester University & Myerscough, that will be studying the strength & weaknesses of Tree forks.

 

Should be a trip

 

 

 

 

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[sean freeman]

Dave, I wonder if they are going to test sample tree unions to destruction or use some variation of the SIA methodology with their own version of the Stuggart Table? It would be very interesting if they did go in the SIA direction,and try to resolve some of the awkward modelling problems....

 

 

Staying with the biomechanics theme of the thread I shot this very basic view of an exposed root plate in the same park that the somewhat inadequate grafting shots were taken (these things look far more impressive in the bark!)

 

I had to play around with the annotations since my voice over description fell well short of providing an accurate explaination of what I was looking at....no great insights but I am always interested to see how an individual tree has resolved some of its biomechanical obstacles.

 

[ame=http://www.youtube.com/watch?v=Mxn73Fo1cXk]YouTube - Tree root morphology of Albizia saman[/ame]

[David Humphries]

Dave, I wonder if they are going to test sample tree unions to destruction or use some variation of the SIA methodology with their own version of the Stuggart Table? It would be very interesting if they did go in the SIA direction,and try to resolve some of the awkward modelling problems....

 

 

Staying with the biomechanics theme of the thread I shot this very basic view of an exposed root plate in the same park that the somewhat inadequate grafting shots were taken (these things look far more impressive in the bark!)

 

I had to play around with the annotations since my voice over description fell well short of providing an accurate explaination of what I was looking at....no great insights but I am always interested to see how an individual tree has resolved some of its biomechanical obstacles.

 

 

 

 

Fascinating find sean.

 

The tape to stop some poor unsuspecting jogger from falling into the pit of doom?

 

Or prep for a spot of mulching?

 

 

Haven't picked up what methodology will be used in the trials but will try and make contact at some point. The project is being supervised ,by Dr Roland Ennos .

 

Not conversant with the Stuggart Table, can you expand a little?

 

Cheers

 

David

[sean freeman]

Yes the hazard mesh was doubtless put there by council but the stakes or pickets have long since been "aquired" by some locals.....

 

The Stuttgart Table is the book of values attributed to the wood tissues from various tree species that were researched in the development of the tree pulling (SIA) methodology.

 

Now I don't know anyone who is qualified 'licensed' to carry out SIA projects here in Oz (there may be some but I just haven't heard of anyone) So my opinions are based on various published articles in journals and various failed attempts to engage the main men themselves, though I can perfectly understand their commitment to bill paying projects rather than curious antipodean arborists.

 

I really do applaud the use of the system to support strongly posited VTA assessments and prevent what were IMO unnecessary tree felling decisions in some more public cases.

 

So the values present calculations relating to the material properties of the live timber from particular tree species grown (not surprisingly) in the city of Stuttgart.

 

These material properties are what through application of the modelling and the mathematical formulae enable the results of the strain gauge measurements during the pull test to provide a value as to the relative strength (or weakness) of the tested tree, the inclination values produced during the pull test together with the material properties derived from the table enable a calculation of the force required to effect windthrow of the entire tree.

[Giles Hill]

Good vid Sean,

 

Is that a drainage channel it's growing on?

 

I'd guess the channel is influencing the length of the root growth from the base of the tree and that there will be a shorter length of roots in other directions, away from the channel? Probably a silly question, because you're not going to dig the rest of the roots up.

[sean freeman]

Yes its an open drainage swale, if you look at the other vid on the youtube page about changing veg in the park, I talk (do I ever stop???) about the draining of what was a Melaleuca swamp and the emerging dominance of the Albizia saman, there are still a few paperbarks in the park one fairly big one in a distant corner that might have been a sapling when the park drainage began.

 

The swale is part of the stormwater management for the local area, townsville is an anachronistic bit of dry tropics jammed hard against the wet tropics to the north, so most of the time it is very dry but every now and again it gets very very wet very very quickly, and this park used to be a landform that reflected that reality...but as population levels rose dramatically and people built in more and more of the emerging township areas like this and others, including mangrove swamps were drained and partially filled in.

 

The erosion in the swale/gulley reflects the volume of storm water we can get on an average season.

 

I like raintrees (A. saman) because they have an odd collection of large physical characteristics that remind me of many other tree species...their root buttresses can be enormous, and they have a strong self grafting habit in their roots and limbs (I know common to many species!) which because of the speed of the increases in circumferential size is always pretty impressive.

[David Humphries]

Over in northern Spain a couple of weeks back, amongst large numbers of old Beech Pollards, could not help but notice many instances of 'support' grafting.

 

Don't focus on the methods of re-pollarding as that's for another thread.

 

Appears to me, that Beech more than any other North Hemisphere species has the greatest propensity to graft.

 

Any thoughts?

 

 

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[David oakman]

I like that David i think it must be time for a thread on mosses and lichen:thumbup:

[David Humphries]

Branch socket Canker on a Sycamore

 

 

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[rupert]

An amazing ancient weeping beech. Unfortunately the photos don't do it justice.