The top of Australia's Snowy Mountains have some very unique environments: the Subalpine snow gum woodlands and the treeless alpine communities. In normal circumstances, a fire with the heat intensity and extent of the 2003 fires might only impact on these environments once in centuries.
Various researchers agree that there is little if any evidence that Aboriginal Australians regularly burnt the high country. Unlike Aboriginals in more arid environments the tribes of the area were not traditional users of fire. They did, however, light fires in the mountains during their summer gatherings. Over thousands of generations, they visited the area for spiritual purposes and they may have used fire to smoke out the Bogong moths from rock crevices and to cook them for their feasts. No documentary evidence exists of wildfires occurring directly as a result of this Aboriginal use of fire, but it is feasible that infrequent fire escapes may have occurred and burnt over limited areas of the mountains.
European settlement and the grazing era In the mountains changed the fire regime in the high country. The graziers burnt their lease areas towards the end of each summer to encourage a ‘green pick' in the following year. A combination of grazing and burning caused severe and widespread erosion and favoured the regrowth of healthy shrubs at the expense of grasses and herbs in the alpine area. The only way to recover the natural snowgrass cover here was to stop burning.
The snow gum woodlands were also dramatically changed over the many years of grazing, followed by prescribed burning programs designed to prevent bushfires, beginning in the 1950s. Fire management within Kosciuszko National Park since 1986 has been more ecologically based with the basic objective being the exclusion of fire from all vegetation communities for fifteen to fifty years or more. This has been a very specific objective for the snow gum woodland communities. Unlike other eucalypts, which very quickly regenerate after fire by sprouting epitomic growth, the snow gums above-ground growth is killed by fire and they can only recover by sending up new stems and trunks from the underground lignotuber. Repeated fire incidents may exhaust the ability of the lignotuber to do this. A long period without fire is necessary for the dense understorey of shrubs to be replaced by grass.
The subalpine woodland with a grassy understorey provides for greater decomposition of the litter fall and higher fuel moisture conditions. This means that the litter has a low fire ignition potential in all but the driest years.
