I willing to experiment with cutting 1/3 off the top of a blue spruce
and it having a good chance of survival.

But I know that as you cut more and more of a tree, some point is reached
wherein the death of the tree results, such as cedar. But some trees can be cut
level to the ground and they emit new trees from their roots such as locust.

So I wonder what genes in tree species tells the tree when it is dead and why
such a variance in percent of cutoff. Cut the entire Locust trunck and it is
still
alive with new trees sprouting from its roots. Cut more than 1/2 of most trees
and they are likely to die.

Presumably once a tree is dead the genes have stopped telling it
anything. But plants have to be able to trigger their own suicide, at
least in the category of monocarpic plants. I believe that each species
can have a different way of promoting cell death, and even instigating
the resultant cell decomposition. But would love to know how many ways
have yet been recorded. Presumably it is not high on the list of
research priorities, tho a gene for monocarpic behaviour might be useful
for controlling invasive weeds.....



--
Martin Cragg-Barber