Re: Australian fires
- Subject: Re: Australian fires
- From: T* &* M* R*
- Date: Tue, 01 Jan 2002 11:31:09 +1300
Just in case the Ozzies are too busy to reply.......
Richard Starkeson wrote:
>
> To the list members in Australia -
> We read about the great fires now occurring in the area near Sydney, and
> I wonder what effect the fire has upon native vegetation. Are eucalypt
> forests adapted to fire?
Yes, definitely. Even without human intervention, lightning strikes
start many fires in the Australian bush every year. The vegetation has
adapted to this environment. Some kinds of seeds will only sprout after
they have been burned over.
The characteristic oil that most eucalypts produce is both volatile and
highly flammable. In the great heat of the Australian summer, the air
"out in the bush" becomes nearly saturated with this oil, and this is
the reason why their fires spread so freely and so fast, a flame can
"flash" through this nearly-explosive atmosphere for some distance, and
the slightest spark flying on the wind will ignite a new fire away
downwind.
Does fire in Australia produce a subsequent
> mass flowering of annuals, or spurts of new growth in shrubs and trees?
Undoutedly the trees and shrubs regenerate fast after a fire and, as
mentioned above, the heat of a fire will trigger germination in many
seeds. Flowering is mainly restricted to early Spring.
> Here in northern California, we had a large fire about 10 years ago that
> went through large eucalyptus groves (I am not sure of the species, but
> were predominantly a single species of gum). A great number of the
> large trees were destroyed, but resprouted from the base about a year
> later.
Not at all surprised, typical of the Genus.
BTW, the smoke of the current fires around Sydney has been drifitng
downwind as far as here - 1500 miles away. Our son who lives 60 miles
north of us says the smoke was a definite "staining" of the air around
them and caused a spectacular sunset a few days ago.
We did not see the smoke here on this occasion - the winds must have
blown it north of us - but we have seen - and even smelt - it in other
years when they have had bad fires over there.
Tony
--
Tony & Moira Ryan <theryans@xtra.co.nz>
Wainuiomata, New Zealand, SW Pacific. 12 hours ahead of Greenwich Time
