Lindsay “Linz” Johanssen, Alice Springs News
Buffel grass (Cenchrus Ciliaris) is not just invasive. Environment-wise, it is utterly transformative. And it is here to stay.
Yet, in the latter, above, to some extent, I hope to be proven wrong.
See my hope is that, one day, an efficient, environmentally friendly controlling agent for buffel will be found … a cost effective means of completely eliminating it from large areas like the West Macs national park, for instance, while at the same time leaving the pastoral industry able to enjoy its undeniable economic benefits.
That said, here – like it or not – is what we are faced with:
Buffel grass is a deep rooted, “woody stemmed” perennial.
Buffel thrives on being burned. Vigorous new growth follows subsequent showers of rain, so recreating (and episodically contributing-to), a new fuel load.
Buffel’s fuel-load mass, at any given moment, is determined by the number, duration and intensity of rain events since the previous fire event.
Little degradation occurs to this fuel build-up in areas not stocked and grazed. It just builds, and builds, and builds … until it burns – generally as a result of a lightning strike.
Buffel fires are often intense and prolonged. It presents to an oncoming fire-front as an upright, well ventilated, high surface-area fuel, with both intensity and duration being determined on the day by fuel load density and mass, plus wind conditions and temperature.
Buffel’s burn / rapid-growth rebuild / ready to burn again fire cycle will, over time, simply kill or destroy everything that is not protected or cannot evacuate – everything! – as its fire repeat-time is far too short for most of the native species to advance beyond the early juvenile stage, let alone reach reproductive maturity.
And this applies in particular to an area’s macro-flora species – the big plants.
Hills country that is already dominated by buffel (such as that immediately north of Alice Springs) is almost totally undefendable, and will, in time, be reduced to bouldery grassland, with few new or surviving shrubs and trees.
And (as much as I hate to write these words), so too the Western Macs, which region, even now, is primed and ready to burn again – along with any other areas that buffel has fully exploited.
Fire risk on low-relief, buffel-dominated pastoral rangelands is reduced to a lesser or greater degree by grazing, depending on stock numbers. And lightning-strike fires can be area-limited by well maintained cross-paddock and fenceline fire breaks, their width factored by cost and practicality (with many of the latter already in place).
As for the West Macs … Well, its great attractions are the magnificent escarpments, its ephemeral river gorges and other high-relief geology, especially viewed in contrast with its extensive rangeland country.
And so, wanted or not, here’s my two dollar fifty’s worth: I reckon that some of its less-visited, less-travelled, low relief rangeland could be well served by having (shock-horror!) some fenced grazing mitigation and/or a few well maintained, fire-size limiting, fire breaks … instead of the anguished hand-wringing that seems to be the response so far, to those horrible and devastating, West Mac infernos.
Correct me if I’m wrong.
This article appeared on Alice Springs News on 4 March 2023.
