To support Ian and Mark's comments -- my memory being as it is
doesn't allow me to provide any verification, but somewhere in the
last couple of years on a lecture / tour / greening australia(?)
exercise somewhere, I heard an expert suggest that hollow trees were
in fact less likely to fall than solid ones, and s/he provided an
example where this had been observed in a windstorm - due to better
strength to weight ratio. I do remember that fact though not the
circumstances, and being impressed by the fact that old trees could
therefore well be justified for safety reasons. Unfortunately I
don't think the same argument applies to branch dropping, but still...
Julian
At 08:46 PM 22/12/2009, Ian Hodgson wrote:
I'm not a tree expert. In fact I know very little about trees, but I
have seen lots of old trees around Australia where the main trunk is
hollow, either as a result of fires or presumably eaten out by
termites. Biut the tree doesn't seem to have died. Maybe that's
because the growing living part that carries nutrients up the trunk
to the limbs is that bit just below the bark; at least that's what
the books say in a more technical way. I'm sure someone will correct
me if I'm wrong.
Also, my recollection from school physics is that a tube is stronger
than a rod. Therefore, wouldn't a hollow branch be stronger than a solid one?
Incidentally, we've had koels calling most nights and first thing in
the morning almost every day for several weeks. We're not that far
from Higgins.
Ian Hodgson
Weetangera
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