ustralia generally. The climate, on the one hand,
which dries up vegetation, and the wandering habits of the natives on
the other, which induce them to clear the country before them by
conflagration, operate equally against the growth of timber and
underwood.
CAUSE OF THIS.
But there is another circumstance that appears to have escaped Mr.
Dawson's observation; which is the actual property of the trees
themselves, as to the quantity of vegetable matter they produce in
decay. Being a military man, I cannot be supposed to have devoted much
of my time to agricultural pursuits; but it has been obvious to me, as
it must have been to many others, that in New South Wales, the fall of
leaves and the decay of timber, so far from adding to the richness of
its soil, actually destroy minor vegetation. This fact was brought more
home to me in consequence of its having been my lot to spend some
months upon Norfolk Island, a distant penal settlement attached to the
Government of Sydney. There the abundance of vegetable decay was as
remarkable as the want of it on the Australian Continent. I have
frequently sunk up to my knees in a bed of leaves when walking through
its woods; and, often when I placed my foot on what appeared externally
to be the solid trunk of a tree, I have found it yield to the pressure,
in consequence of its decomposition into absolute rottenness. But such
is not the case in New South Wales. There, no such accumulations of
vegetable matter are to be met with; but where the loftiest tree of the
forest falls to the ground, its figure and length are marked out by the
total want of vegetation within a certain distance of it, and a small
elevation of earth, resembling more the refuse or scoria of burnt
bricks than any thing else, is all that ultimately remains of the
immense body which time or accident had prostrated. Thus it would
appear, that it is not less to the character of its woods than to the
ravages of fire that New South Wales owes its general sterility.
CONNECTION BETWEEN THE GEOLOGY AND VEGETATION.
Whilst prosecuting my researches in the interior of the colony, I could
not but be struck with the apparent connection between its geology and
vegetation; so strong, indeed, was this connection, that I had little
difficulty, after a short experience, in judging of the rock that
formed the basis of the country over which I was travelling, from the
kind of tree or herbage that flourished in the soil above it
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