On Fri, 21 Jan 2011 13:29:10 +1100, "Peter Jason"
wrote:
I live in a dry area.


If I dug (or bored) a deep 10 meter hole and planted a small
sapling at the very bottom and then left it alone:

10 meters is probably too deep.

1/ Would its closer proximity to the water table be of
assistance?

Yes.


2/ Would it grow (albeit etiolated) upwards towards the
light for the whole 10 meters? And then produce foliage as
normal?

When a deep hole planting method is used, the sapling is generally
long enough to stick out of the hole.

3/ Would the beginning of the root system stay at the 10
meter interface, and would the roots grow downwards to the
degree (depth) as though on the normal surface.

A lot depends on where the water is. You won't get any surface roots
if there is never any surface water.

4/ Would the nett effect be to have a plant (tree) in a
desert area with deeper roots than those planted at the
surface?

Yes, this method is practiced as part of Permaculture.


Please help,

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