Tending Fires
By Roger Underwood
(First published in The Forester Volume 52(2) 2009. The Forester is the newsletter of the Institute of Foresters of Australia.)
IN THE WAKE of the 2009 Victorian fires there have been the usual claims by the Canberra intelligentsia that fuel reduction by prescribed burning is valueless as a bushfire mitigation measure. The assertion is that bushfires result from high temperatures and drought, and that heavy fuels are not a factor.
I am nonplussed by these views, because they fly in the face of simple physics, of fire behaviour research and of the personal observations of firefighters. These all confirm that when a bushfire burns out of an area of heavy fuel into one of light fuel (for example an area burned only two years previously) the fire intensity drops, the crown fire becomes a ground fire, flame height and flame length decrease and heat output falls.
There are qualifications. Although the benefits of fuel reduction can last for 15 years, the most effective areas are those where fuels are 2-3 years old or less. Fuel reduced areas need to be of sufficient size and depth, or a fire will go over the top, or burn around them. And in a situation where a fire has developed such intensity as to generate its own wind, it will throw spotfires miles ahead, resulting in a situation where many fires coalesce into one fire. Nevertheless, the general rule always applies: fires burn less intensely and spread more slowly in bushland with light fuels compared to those with heavy fuels, other things being equal.
Why is this principle denied, or so misunderstood or seriously misrepresented? How is it possible for educated and intelligent people to believe, and keep saying, that fuel reduction makes no difference, denying both science and real-world observation?
One explanation is that they argue from a false premise. This is the oft-heard assertion that “there is no evidence that fuel reduction burning prevents bushfires”. Of course it does not, and no-one claims that it does. Forests subjected to fuel reduction programs will burn again, a fact recognised by the necessity for burning cycles, quite apart from simple observation. The proposition that “fuel reduction does not prevent bushfires and is therefore useless” is classical crooked thinking, and cannot be debated since it is true. What fuel reduction does is to make fires easier and safer to control, and ensures they do less damage – both to the environment and to human values.
Perhaps there is a more simple answer: many people these days, and most academics, have almost no contact with fire in the real world, have never measured fire behaviour in different-aged fuels, or been involved in fire management operations. Moreover, a whole generation of Australians have now grown up who do not even use fire domestically, let alone become involved in burning or fighting bushfires.
I had an insight into this recently when I was entertaining two of my little grandchildren on my property at Gwambygine over the school holidays. I decided one day to teach them how to make a billy out of an old can and some fencing wire, how to light a camp fire, boil the billy and make tea, how to cook sausages on an old plough disc mounted on some stones, and make a damper in the ashes – in other words, basic bushmanship, thoroughly familiar to 90% of Australians a generation or so ago. This was fun, but also instructive. I found I was teaching them fundamental lessons about fire behaviour……that you could bring the billy to the boil by making the fire more fierce (by adding fuel), that you could cool a fire so as to prevent the sausages burning (by taking fuel out, or shifting it apart), and that you can resurrect a dying fire by blowing on it (adding oxygen). In other words, fires could be tended and the fuels managed to influence fire intensity (heat output) and get a particular outcome.
Thinking about this afterwards, I realised that nobody had ever taught me any of these things, nor did they need to do so. I just learned them as a natural part of growing up in the 1940s in a house where we had a wood stove in the kitchen, an open wood fire in the sitting room, a wood-fired copper in the wash house and a woodheap and a woodshed out the back. My first job after leaving school was as a “billy boy” in a forestry gang at Dwellingup. All through my early married days, and right up into the 1990s my wife and I cooked on a wood stove, and we still enjoy an open fire in the loungeroom hearth on winter nights.
Modern urban children like my grandkids never see a real fire from one year to the next. Their food is cooked on an electric stove, there is central heating in winter, an electric hot water system, and a gas BBQ out the back. They don’t even get to burn the leaves in autumn. Although no doubt they would have an intuitive understanding of the relationship between fuel and fire intensity, they have no practical experience of the opportunity for manipulatiing the variables that determine fire behaviour, and observing the outcomes.
Australians of my generation were accustomed to the idea that managed fire was a friend. At that time, farmers were still clearing the bush. The use of fire to help with clearing, as well as to reduce fire hazards or clear away stubble, was simply another aspect of land management in the Australian environment.
A whole generation of Australians has grown up now without any of these experiences and another generation is following in its wake. These people have never seen fire used as a tool, or used it themselves even for simple tasks like boiling a billy. Their only exposure to fire is on television where it is invariably portrayed as an enemy: an evil destructive force, killing people and burning down their houses. They have no contact with the tiny minority of the population who use fire professionally like foresters, farmers, Aboriginal communities and some park rangers or volunteer brigades. Indeed because of the perverse way prescribed burning is treated by our education system, they grow up believing that burning is anti-environment and anti-social (when the opposite is true). Some of these young people will end up going to University and becoming academics and teachers or national park administrators, never having worked in the bush, let alone worked with fire, thus reinforcing and perpetuating the disconnect between beliefs, experience and real knowledge.
I can’t see kids becoming more involved in fire in a practical sense. The Australian population is simply too highly urbanised, and becoming more so. Therefore, unless there is a fundamental change in the way fire science and bushfire management is taught at schools and in our universities, everything points to the fact that it is going to get harder, not easier to conduct fuel reduction burning programs in the future. This in turn will lead to more and more horrible fires, as fuel reduction is the only measure at our disposal for minimising bushfire intensity.
I have three great hopes. The first is that the human survival instinct will kick in for people living in the bush and threatened by increasing numbers of unstoppable fires coming at them from long-unburnt forests. This instinct will drive them to seek effective measures to cut the rate of death and destruction. They will discover, as an early generation of Australian foresters did, that the only way to do this is through a progam of fuel reduction prescribed burning. This will start to shift the balance of political agitation from anti- to pro-burning.
My second hope is that the environmental movement in Australia will, as it has in the United States, discover that biodiversity is enhanced by habitat diversity which in turn is enhanced by fire diversity. They will realise that mild frequent fire is a natural ecological factor leading to healthier, more ecologically resilient and more beautiful bushland. The stories and legends of the Aboriginal people and their use of fire will be resurrected and supported, rather than rejected.
To be honest, I can’t see this happening in the short term. The generation of environmentalists who fear fire and are uncompromisingly committed to an anti-burning positon will first need to disappear or be marginalised. However, when this happens a new generation of enlightened greens (taking their lead from the USA as they always have) may well start to condemn forest managers for not keeping up with their burning programs, instead of trying to stop them burning.
Finally there are the corporate conservationists, organisations like the Australian Wildlife Conservancy, who own extensive tracts of Australian bushland and are steadily putting in place very professional species recovery and land management programs. These organisations are not dependent on public funding or on getting elected and are therefore not vulnerable to green pressure groups. Unlike many government agencies, AWC can follow the dictates of science and experience without fear of political fallout. And they are doing so, setting an example in their use of fire that national park and wildllife agencies could well copy. The results of this work will soon be apparent to all: large bushland reserves where concurrent management for fuel reduction and habitat diversity is leading to significant environmental and community benefits.
Thus, a serendipitous coalition of interests might arise between newly-enlightened environmentalists, corporate conservationists and bushfire-threatened communities at the urban interface. This would swing the pendulum away from an unmanaged to a managed fire regime, and would prove difficult even for the powerful Canberra intelligentsia to overcome.
Time will tell. In the meantime, I am preparing a submission to the Minister for Education pressing for “billy-boiling” to be added to primary school curricula.
April 2009
Author Roger Underwood is a renowned Australian forester with fifty years experience in bushfire management and bushfire science. He has worked as a firefighter, a district and regional manager, a research manager and senior government administrator. He is Chairman of The Bushfire Front, an independent professional group promoting best practice in bushfire management.
For other works by Roger Underwood, see [here]
