When forming a Fuel Reduction Burning program, many aspects must be considered. CALM are the main organisation who plans these burns and their regime. They seek to minimise the visual effects of planned burns and wildfires, but at the same time completing the task of reducing fuels. Therefore planned burns are lit under the coolest conditions that will provide effective fuel reduction; the height of the treetops is used to decide the maximum fire intensity, reducing the risk of scorching; burns are confined to one side of a tourist road in the one season, or are set back from the road edge, minimising visibly burnt bush.
However, sometimes a few burns do escape the boundaries set for them, usually due to unpredictable wind change. Therefore a prediction system must be implemented which takes into account fuel accumulation and the effects of different wind speeds, temperatures, relative humidity, fuel dryness and the slope of the land.
Photo - Tom Leftwich, Autumn 1994 Landscope
Planning for a proposed burn takes place up to eight years ahead. This allows for CALM to plan for the needs of other forest activities such as tourism, commercial operations, and habitat regeneration. Buffer zones (400m to 3kms wide) are identified where fuel reduction will be needed. All environmental impacts must be assessed before a burn is approved, after which all involved persons, assets, properties or operations are identified. As the area and requirements differ from burn to burn, the preparation of a set of objectives must include a calculation of the type of burn which will meet them, the weather and fuel moisture which must exist on the day of the burn, and the lighting pattern to be adopted.
When the planning stage is complete, warning signs are placed and announcements are made on ABC radio on the day of the burn. CALM staff compare the set day’s weather forecast, fuel moisture conditions, smoke dispersal etc. with the conditions prescribed. If the conditions match then the burn goes ahead, under the control of professional crews.
The planned burning program has a wide range of constraints. Weather conditions, limits to funds and manpower, and the need to avoid special areas all create certain restrictions. Also, the Bush Fires Act states that burns cannot be performed on days of very high fire danger; and burns are usually undertaken during a period determined by the local government authority. The constraints have resulted in a decline in the area burnt each year, and therefore fuels are left to build up.