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Re: Do Trees ever die of Old age

Posted: September 15th, 2011, 3:16 pm
by Bretts
You can hear me babbling on here
http://www.abc.net.au/science/audio/201 ... 318558.htm

That is the crux of the matter Vice. I am out of my depth in understanding how the cells in trees work but Dario suggests
Same goes forn the cambium...as it divides/reproduces, the outside of the cambium becomes the phloem and the inside becomes the xylem. So the actual cambium is only ever up to 2 or 3 yrs old and when it regenerates itself it pushes the oldest (outer most) portions of itself to become phloem/bark, and the oldest (inner most) portions of itself to become xylem/sapwood. That is how the growth rings are formed/generated, but the actual living cambium always remains young.
So part of the question would be whether there is any difference in the aging of the cells in the cambium and the new shoots of the tree. I have considered if the scenario of a shoot cutting would be any different to a tissue culture taken from the cambium of the trunk (and if this is even possible but I think it is) as to whether it would again have a full life.

My simple understanding of the issue tells me that a tissue culture from any part of the tree would go on to enjoy a full life if propagation was successful. If so what part of the tree is actually aging???

Dr Karl mentioned an Aussie lady by the name of Dr. Elizabeth Blackburn. The first Australian Lady to win a Nobel Prize for her work in this area. I am going to email here a brief explanation of the question and see if she will shed some light on the issue for us.
I find this subject interesting as I never understood how our cells degrade every time they divide but those cells are able to recreate new life over and over in sexual reproduction without a lessened life span. I get the feeling there is a conextion in the explination.
Complicated stuff but I find it very interesting.

Re: Do Trees ever die of Old age

Posted: September 15th, 2011, 3:46 pm
by Vice
Bretts wrote: Complicated stuff but I find it very interesting.
Me too, Immortality is my goal in life.

Let us know what Dr. Elizabeth Blackburn says if she or her department replies.

Re: Do Trees ever die of Old age

Posted: September 15th, 2011, 7:54 pm
by Andrew Legg
OK people. No forum like this would be complete without a graph so here goes!!!
Cambium to trunk volume ratio.jpg
This graphs cambium volume to trunk volume and is probably entirely pointless! :cool:

What it does tell me thought is that the ratio between cambium volume and trunk volume is a square function. It would seem that the tree needs to get past the first 10 to twenty years of growth before the ratio seems to stabilise. That said, what this does not take into account is the ratio between the sapwood/heartwood and cambium layers and also the ratio between foliage mass and cambium volume - a bit more difficult to plot off the top of my head! :lost:

Anyway - all that said, I still think this thread is much better now that it has a graph. :whistle: