Bushfires in central Australia fuel debate about whether buffel grass or native grasses burn more intensely

Huge bushfires in central Australia have ignited discussions about the role of buffel grass in increasing fire risks ahead of a recommendation on whether or not the plant should be declared a weed in the Northern Territory.

The Northern Territory’s buffel grass technical working group has been assessing the impacts and management strategies of the introduced plant since March.

The group had its final meeting on Thursday before presenting a recommendation to the Environment Minister by November 30 on whether the species should be declared a weed.

Buffel grass is valued by some as cattle fodder, to control soil erosion and as a dust suppressant, but it concerns other groups because it can become a monoculture and reduce biodiversity, impacting tourism, Aboriginal culture and the environment.

The large swathes of land burnt in the Northern Territory this year have been attributed to climate change, arson and huge fuel loads after a wet summer, but fires in arid central Australia have also prompted widespread discussion on whether buffel grass generates more intense fires than native plants.

Who says buffel burns more intensely?

The Arid Lands Environment Centre’s Alex Vaughan said buffel should be declared a weed partly due to the plant increasing fire risks in central Australia.

“We know that buffel grass creates hotter, larger and more frequent wildfires,” he said. 

Central Land Council, which supports traditional owners to manage land across 777,000 square kilometres of central Australia, would also like buffel grass declared a weed.

General manager Josie Douglas said buffel grass fires were bigger and more destructive than other grasses because of the high fuel load.

“The fires are much, much more intense than when native grasses are burning,” she said.

Not everyone thinks buffel is to blame

Central Australian pastoralists Ben and Nicole Hayes said about 60 per cent of their property, Undoolya Station north east of Alice Springs, burnt in recent fires, but the ferocity of the fire couldn’t be attributed solely to buffel grass.

“For those under the misconception that the severity of these fires have been due to buffel grass, they are totally wrong,” they posted to Facebook. 

“Native grasses like spinifex, kerosene, kangaroo grass, along with trees like Tea Tree, Cork Wood and others that explode and send embers flying have been our biggest battle.

“That country that’s burnt up here, there’s hardly any buffel in it. That’s all native pasture,” Ben Hayes said in an interview with ABC Alice Springs. 

Tony Davis, a 76-year-old pastoralist, also blamed native grasses for the fires that tore through thousands of hectares of his Amburla and Hamilton Downs properties northwest of Alice Springs earlier this year.

“The worst fires have been where the buffel grass isn’t,” he said.

“I’m just getting a bit sick of hearing about all this buffel.”

What do researchers say?

Charles Darwin University’s Christine Schlesinger has researched buffel grass for about 15 years.

Dr Schlesinger said buffel grass could put on biomass very quickly, which created dense fuels compared to native grasses, leading to more severe fires.

“All the evidence shows that fire through a buffel grass area is much more damaging,” she said.

“In these really high rainfall years, it doesn’t matter if you’re grazing buffel. That’s not enough to reduce fuel loads to a safe level, so what we’re seeing is increasing fire on pasture or properties.” 

CDU arid lands ecologist Dr Marg Friedel said the speed and intensity of fires depended on factors such as moisture levels of vegetation and soils.

“It’s very unwise to generalise about buffel grass versus other vegetation because of all the variables that people don’t necessarily recognise, and there’s often a lot of local variation,” she said.

“I would think the pastoralists would know their country better than anyone.”