The
dead leaf test
15
June 2000
Sunday
night was cold and wet and the Mount Kuring-gai tragedy was still the
talk of the Brushtail Cafe. A couple of Joadja's old mates from the
National Parks and Wildlife Service dropped in to talk it over. They
were just leaving when I came down from the office.
I
shook hands and muttered condolences and my hopes for those still in
intensive care. Bruce and Tarkis looked respectfully from their stools
at the bar, with the air of those on the threshold of a world beyond
their experience or, perhaps even, imagination.
"How
could something like this happen?", said Tarkis, after the rangers
had left. "They say it was just a routine operation, with perfect
conditions".
Joadja
snapped a banksia leaf off the big arrangement of dried wildflowers
at the end of the bar and picked up a cigarette lighter. Pinching the
leaf's stem between her thumb and forefinger she held it pointing straight
down and lit the tip. It flared and began to burn up, towards her fingers.
"Watch
this", she said. She turned the leaf slowly till it was horizontal.
It continued to burn, then, slowly, she turned it upwards. It hadn't
quite got to the vertical plane when it gutted out. I had seen this
before, but Bruce and Tarkis looked on, wide-eyed.
"Old
firefighters's trick: they call it the dead leaf test. If it had kept
burning down towards my fingers while it was pointing straight up, I'd
have known the bush was explosively dry", she said.
"But
it didn't, because it's been raining, and humidity's gone up, and even
this dried-out old leaf has absorbed some moisture from the air. Give
it a dry day or two, or a few really hot hours and it would burn straight
down.
"The
bush is like the sea. You have to watch it from hour to hour, like a
rock fisherman or a sailor must watch the sea from moment to moment.
And even if you do that, you might still be caught by some freak condition,
because nature is infinitely variable."
Jo
dropped the leaf in the bin, and I took a sip from my cider.
"So
waddaya reckon they should do? Do you think they should burn these places
more often, you know, so they're less dangerous?" Bruce asked.
"Look,
there's a lazy bit of pop ideology which insists we should burn the
whole of the east coast every year", Jo said. "During the
big fires of '94 it became an article of faith with the political Right
-- all the radio shock-jocks took up the cry -- but it's really a bit
of irresponsible gibberish. Like most things concerning nature, it just
isn't that easy, or even possible. You have to look at it practically.
In some years it rains too much. The bush gets so damp you just can't
light it up, so you can't do any hazard-reduction at all.
"Even
in the best years you only get a small window of opportunity -- just
a few weeks -- when you can do a burn-off safely -- then suddenly it
gets too dry. If you light up, the burn takes off and runs out of control.
Lots of wildfires have started as hazard-reduction burns that went wrong.
"It's
a really tricky thing to manage. It takes lots of professional planning
and it isn't cheap. When you're doing a burn-off near homes -- and there's
thousands of kilometres of interface between the suburbs and the bush
-- you need scores of properly trained firefighters, with fire tankers
and helicopters and all the rest. The great Aussie dream of living on
a ridgeline in a split-level home cantilevered over a bush valley has
a terrible downside."
It
sure has, I thought. The National Parks mob had suffered more deaths
and worse casualties when something freaky happened during a routine
burn-off than the whole of the Timor intervention force has experienced
so far.
INCLUDED
in Whispers from the mean streets
-- Best of 2000
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