[Music plays]
(Narrator) Nothing engenders fear and horror among Australians
like a summer holocaust.
Wildfires like this can bring down in minutes
what has taken a lifetime to build.
[Fire crackles
Fire, though, is a natural part of the Australian environment.
It’s been as regular as summer itself for thousands of years.
In fact fire has been such a dominant factor
that many native plants are adapted to periodic burning.
But fire out of control is no respecter of man or beast.
It’s not surprising that so much effort in manpower
and equipment is applied to suppressing fire in Australia,
but this destructive power of bushfires, properly controlled,
could be worth a lot of money to hundreds of graziers.
Working in semiarid woodlands of Eastern Australia
scientists from CSIRO’s Division of Land Resources Management
have found that the suppression of fire is not always for the best.
When the pioneers pushed inland from the coast with their sheep and cattle
they found vast open and grassy woodlands with abundant feed for their animals,
but gradually, and then dramatically, the landscape began changing.
So much so that today a vast area of some 400,000 square kilometres,
extending from Central New South Wales into Central Queensland,
is being choked by a dense sea of invading shrubs.
The CSIRO scientists believe the reason for the change
is partly due to overgrazing by sheep and rabbits,
which have removed the grasses and given the shrubs the competitive edge,
and ironically the efforts of settlers.
CSIRO Range Land Ecologist, Doctor Graham Harrington.
(Doctor Graham Harrington) Well we know that
fire will kill many of these problem shrubs,
and we also know that since Europeans arrived in this country,
about a hundred years ago, the frequency of bushfires has been greatly reduced,
and this coincides with the growth,
this vast increase in growth of shrubs that we see here today.
(Narrator) The invading shrub is literally forcing sheep off the land,
as grazier George Lucas knows only too well.
When he bought his property, Clifton Downs,
at Yantabulla in the far north of New South Wales in the early 1960s,
he could muster this paddock alone in a matter hours.
Now, with a dense cover of shrub, it take three men twice as long,
and even then they can never be sure of a complete muster.
The ability of his property to support livestock has been reduced by 50% in recent years,
and his chances of finding sick or injured sheep are almost nil.
The CSIRO research team believes the shrub will survive the next drought,
but the grasses won’t, which means that when the drought breaks
the grasses will not re-establish.
And not only the sheep suffer,
the shrubs are depriving the red kangaroo of its natural habitat,
and creating a haven for feral animals like pigs and goats.
In an effort to push back the shrub and restore the natural balance
Doctor Harrington and his team are carefully
reintroducing fire into the woodlands.
But is fire foreign to this environment?
(Doctor Graham Harrington) Well no,
fire is a natural part of this environment,
either lightening fires, or Aboriginal started fires,
and knowing this, and knowing that it was open country before Europeans got,
or when Europeans got here,
we’ve been carefully reintroducing fire into this system,
and as you can see here it’s very effective.
These shrubs are dead.
[People talk on radio]
(Narrator) Years of experience in studying bushfire behaviour
go into ensuring that scientists have a controlled, not a wildfire.
But given the traditional Australian attitude towards fire,
is there a better way of bringing paddocks back to productive operations?
(Doctor Graham Harrington) Well we’ve looked
at the all possible alternatives,
herbicides, mechanical clearing, goats,
and they’ve either proved ineffective,
or they prove far too expensive to have any hope
on this large scale of controlling this scrub.
(Narrator) Burning often causes seeds of shrubs to germinate
therefore a second fire is necessary to kill off these seedlings.
The management of paddocks after the fire is also important
to the success of the technique.
Animals favour burnt country,
and the graziers need to be careful
not to allow rejuvenated vegetation to be overgrazed,
so an important part of the continuing research
is the study of the migratory habits of kangaroos and goats into burnt areas.
Just how strong a chance does the CSIRO experiment have
of solving the shrub problem?
(Doctor Graham Harrington) Well our research program has got
quite a few points to follow up yet
as to how fire can be incorporated into property management,
but what I am absolutely sure of
is that there is no alternative to fire
to stop this country from thickening up
so that it will be no longer productive as far as sheep are concerned.