By Bill Brown – 11th Feb 2016
Aboriginal custodians say a massive 2,000 square kilometres of eucalyptus viminalis, known as Manna Gum or Ribbon Gum, that has died on the Monaro Plains in New South Wales is the result of a lack of traditional burning practices.
Video: Dr Cris Brack explains the loss of 2,000 square kilometres of Manna Gum on the Monaro Plains, while traditional custodian Aileen Blackburn says a lack of traditional burning is a factor and should be a part of future land management.
Forest scientists cannot determine a specific cause and say the question now is what to do next.
“This is what’s happening to Australia,” Dr Cris Brack from the Australian National University said.
“This may happen again. There are other examples where you have species on the limit of their natural range, and if we have an event that’s caused stress, maybe other populations like this will disappear.”
Dr Brack said the species had a wide range in Australia, and was the dominant species on the ridges and hills of the Monaro Plains.
“What you are left with looks like a sea of dead, standing trees.”
Dr Brack and PhD student Catherine Ross have surveyed the extent of the dieback and investigated possible causes including agricultural practices, loss of the predators that control tree parasites, weed spraying, and even cloud seeding.
He said because the affected area was so vast then any single cause must equally be present on the same vast scale.
“We haven’t been able to come to a conclusive answer to that — we don’t know. So we think it’s probably a combination of a whole range of things,” he said.
“So people immediately say ‘Oh, so it’s climate change’. It’s an easy answer.”
“It’s not conclusive proof that it is climate change, but if there was climate change this is the sort of thing you would expect to happen.”
Dr Brack said they had been trying to identify the initial cause of the decline, but they suspected that once it began there had been a combination of stresses including drought, and finalised in insects attacking the weakening trees and causing a relatively swift end.
Calls for traditional Aboriginal burning to be part of future land management
Aileen Blackburn, a Ngarigo traditional custodian, points to a lack of traditional low-intensity burning as practised by Aboriginal people for thousands of years until European settlement.
“That would be one of the contributing factors and it would be a big contributing factor,” she said.
Dr Brack agreed that eucalypts had co-evolved with the use of fire by Aboriginal people.
“Certainly fire has a place. The fire can change the soil’s physical properties, change the nutrient effects, you encourage some species and discourage others, and we know that Aboriginals did use fire,” he said.
“That being true doesn’t mean that everything is being caused by a different fire regime. It may be a cause in some additional aspect, but it can’t be the primary cause.”
But Ms Blackburn said it was an opportunity for future land management solutions to benefit from Aboriginal knowledge and culture.
“Had we practised our traditional land management tools, burning one of them, we would have had a different outcome,” she said.
She said European settlers failed to recognise the land management knowledge of Aboriginal people.
“Their perceptions of us was that we were just savages, so what would we know about land management?” Ms Blackburn said.
“There was that hurdle, whereas that’s starting to break down a bit now. That message is getting through that cultural burning was one of our practices.”
She said the Aboriginal perspective went well beyond techniques.
“Of course a lot of it was linked to our respect and ties for the land,” she said.
“The land has a soul and a spirit and we have to look after that too. It’s spirit needs saving. Let’s get some soul back into the country.”
First steps towards finding a solution
“Whatever the causes may have been, the problem is that the species in the Monaro Plains will not recover,” Dr Brack said.
“The big question is now where do we go?”
He said one of the biggest problems was that there was no single entity in place with the mission to deal with a region-wide environmental crisis like this.
“Maybe we need a centre that allows us to pull together a range of disciplines that allows us to work on an area-based study,” Dr Brack said.
The NSW Government recently announced funding of $499,460 over a 10-year period for Greening Australia and the CSIRO to work on a recovery strategy.
The project will involve seed collection and planting trials in a search for resilient species as well as traditional Aboriginal burning trials on Travelling Stock Reserves to evaluate the outcomes upon remnant species.
Greening Australia project co-ordinator Nicki Taws said it was hoped the traditional burning trials would result in stimulation of species recovery.
Forest scientist and advocate for ‘Firestick Ecology’ Vic Jurskis welcomed the proposed traditional burning trials.
“Chronic eucalypt decline is happening all over Australia and it’s a consequence of a lack of burning,” he said.
“It is important for Aboriginal people and non-Aboriginal people to re-establish knowledge.”
Dr Brack has also welcomed the project but stresses that similar forest decline needed to be monitored across Australia and identified in its early stages.
“If we use the Monaro study as a jump-off platform to start looking for where this is happening in other parts of Australia maybe we can get a head start on those ones now.
“Hopefully we can make this into a real pathfinder type of project.” he said.