Interesting Biomechanics

[daltontrees]

no need to doubt it it tallies with matthecks work, and when you use the tensile triangle/force cone/shear squares thinking is self explanatory hence conclusions drawn by Cassian and others

 

I'm not sure I'm with you there. Cassian hasn't proven anything, his article is educated and experienced speculation but it falls far short of normal standards of perr-reviewed science. I don't mean to belittle him, but the notion of two opposite direction helixes of wood on a stem is a theoretical impossibility. By this I mean that vascular tissue cannot possibly cross and yet continue to put on annual increments. The inner part of the crossing pair would be crushed and strangled, cutting off water flow upward and killing the part of the tree served by it, unless there is a mechanism to replace the flow somehow. It's quite a challenge to explain even in theory how this could be done.

 

I have no doubt whatsoever that braided structures are stronger per unit weight than unbraided ones, and have good flexibility characteristics too. After all, I climb and lower on braided ropes almost daily. But ropes don't need to grow. Right there the usefulness of the comparison ends for me.

[sloth]

Leftfield theory... a small epicormic was bent into ground contact by a fallen (now gone) branch and has rooted, establishing a strong downward union. This is about the only thing I can think of to explain the nature of the bark above the 'root'.

 

Sounds quite possible any number of things could have been leant against the stem at one point or another.

 

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[treeseer]

Given all the variables, if we persist in insisting on standards for peer-reviewed science to draw any inferences about mature tree growth, that seems excessively limiting.

 

Vascular tissue could possibly cross and yet continue to put on annual increments. The inner part of the crossing pair might graft to the outer, maintaining water flow upward and sustaining the part of the tree served by it.

 

Why couldn't grafting (perhaps not the best term) be the mechanism to keep resources flowing? These are not impervious pipes after all.

[David Humphries]

a ginormous Liriodendron burr

[treeseer]

a ginormous Liriodendron burr

 

Ginormous, to say the least! And it looks like healthy tissue too.

[David Humphries]

another large burr, this time on oak buttress.....

 

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[Fredward]

Interesting butress/root crowns, erosion?

[David Humphries]

Yes Fred

 

Sandy soil at this point of the site.

 

 

 

 

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[Fredward]

Anyone see this?

 

Someones got a boner for burls

 

Pretty sad

[treeseer]

another large burr, this time on oak buttress.....

 

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Ugly one, that. Looks like much of it is bark?

 

The last pic, next tree over from the burled specimen...the buttress facing the camera has a horizontal bulge; it's a 'belted buttress'.

I'm still trying to figure these things out--if anyone has a clue beyond 'perhaps evidence of vascular discontinuity' or 'smells like honey', I'd love to hear it.