Bundarrah Days

I WAS corrected on The Age Your Say blog the other day for criticising The Wilderness Society's campaign manager, Gavan McFadzean after he confused the terms fire tolerant and fire resistant.

Victor Svatek says I got it all wrong and explains the facts to me. Unfortunately I didn't get a chance to reply to Victor because The Age closed the thread. He said:

"Phil Maguire, I take it you are referring to my attempted explanation of the difference between "fire tolerant" and "fire resistant". So let me have another go...


Fire tolerant species: is relatively easily flammable, normally survives fire (i.e. "tolerates" it and does not "resist" it), and may benefit in terms of reproduction, exclusion of competing species, etc. Examples include most types of eucalypts, especially the drier ones such as the stringybark (I think).


Fire resistant species: is not easily flammable under most conditions (i.e. "resists" fire) but when it eventually gets burned it normally dies (i.e. does not "tolerate" fire; therefore you could also call it fire "sensitive"). Rainforest is the most obvious example. Mountain Ash is also an example to some extent. It needs fire to reproduce, however, the standing trees normally get killed by fire. Mountain Ash by itself does not really resist fire but because it often comes with a rainforest understory an old growth Mountain Ash forest will normally be fire resistant to some extent (it's all a matter of degrees)."

Firstly, mountain ash forests do not have a rain forest understorey, they have a wet schlerophyll understorey which is substantially different. They carry a massive load of fine and heavy fuels due to infrequent burning and in a dry summer they can explode. Mountain ash is not fire resistant in the sense in which Victor means, nor are they fire resistant in the way I interpret the term.

David Ashton, botanist and expert on Victoria's mountain ash forests says:

"The dry eucalypts have developed all these resistant buds and bark and underground parts. They can be burned and come back within weeks." (They are what we call fire resistant or fire tolerant.)

On the other hand Mountain Ash as a species is highly fire sensitive.

Parks Victoria's Mountain Ash information page tells us that:

"Other than old age, wildfire is the only other common cause of death in Mountain Ash. Characteristics that cause this tree to be fire sensitive include the long ribbons of hanging bark and the extreme combustibility of the foliage."


Finally Museum Victoria says this about the Mountain Ash:

"The tall Mountain Ash does not regenerate naturally except through the agency of bushfire, when in its death throes the trees set seed in the smoking ash bed. Indeed even the tree's form and chemistry makes it highly flammable. Living amongst the tall forest might be likened to living amongst a forest of live matches!"

But all this argument is really unnecessary. Svatek is trying to defend McFadzean who was discussing fire in the Victorian Alps and the only real example he can provide of what he calls "fire resistant" is rainforest which isn't relevant to the discussion. Rainforest makes up only a tiny proportion of our forests. For example, in East Gippsland it accounts for about one per cent of the forested area. And it's not fire resistant by any means.

The facts are plain and to try and claim that the terms fire resistant and fire sensitive are the same is incorrect. However, fire tolerant and fire resistant can be and are used interchangeably.