Fire and Storms

Here in Oz the Munchkin legend has arisen that you can only fight fire with fire by ‘backburning’, and the bush will recover and prosper – the Aborigines did it, after all – but their practices were radically different from ours. On this continent that was only ever true of the dry interior, grassy beach fringes and the variable tropics, and not at all best or usual practice on the coastal fringes and foothills where most of the population now dwells – which were mostly rainforest.

Fire destroys rainforest and encourages pyrophytic – fire-loving – species such as the vast majority of gum (eucalyptus) trees. These trees, in turn, love fire and create great conditions for MORE fire. Most fire-loving trees evolved in the high and dry country; the valleys that were cleared for settlement and agriculture were almost all millennial rainforests (except where the soil was too nutrient-poor or dry). The hills and mountains, dry and regularly struck by lightning, were the home of the gum trees – with a few notable exceptions that could thrive on the edges of and within the wetter, multi-canopied shade forests of the valleys and gullies. The primeval mosaic of dry and wet forests meant that wildfires rarely travelled far before being damped down.

Rainforest trees and plants will rarely burn – unless infiltrated by more combustible types. Their canopy promotes the retention of water, holding off evaporation and encouraging springs to rise to the surface. Encouraging rainforest and discouraging fire-loving species is what’s required to save humans and their ecosystem here.

In practice it’s all a little more complex; some species of drier-type trees are required by all sorts of endangered animals and birds. Many mature eucalypts won’t burn, but almost all inhibit the growth of non-eucalypts and provide a ready and plentiful source of combustible wood. By comparison, it’s very hard to actually get most rainforest wood to burn.