Australia’s national floral emblem the golden wattle is now a sitting duck for newly evolving plant pests after the Australian Government failed to deal with the recent invasion of myrtle rust, a deadly plant-killing disease that has infested NSW, Queensland and most recently Victoria.
“South African foresters are warning that new diseases attacking Australian wattles grown in plantations in Africa and Asia will reach our shores,” said Invasive Species Council CEO John DeJose.
“But the Australian Government is yet to develop contingency plans for these and other looming threats to our natural environment arising from overseas incubators. ISC first warned of this issue in July last year (1).”
A recent paper in the scientific journal Diversity and Distributions shows that new, potentially devastating pathogens are poised to strike Australia’s environment.
“Incubated in plantations growing Australian wattles overseas these new pathogens have evolved the ability to infect several wattle species, just as myrtle rust learnt how to exploit the weaknesses of our eucalyptus species,” said Mr DeJose.
“We now fear these ‘new encounter’ pathogens will reach Australia where they could cause serious damage in a landscape full of wattles that have never developed immunity.”
Australia’s biosecurity system has no contingency plans to deal with these new pests and diseases, despite the ecological importance of wattles (our biggest genus of vascular plants – more than 1000 species) and despite having adequate warning in the form of the unfolding myrtle rust catastrophe.
“Many years ago, when myrtle rust jumped hosts and attacked Australian eucalypts in South America, concerned scientists started warning of its arrival on our doorstep,” said Mr DeJose.
“The failure of our national biosecurity system to quickly detect and appropriately respond to the extreme risks posed by myrtle rust now has scientists concerned about the level of government commitment to keeping Australia free of harmful environmental pests.”
Plant Health Australia assessed myrtle rust as:
- High potential for entry to Australia.
- High potential for establishment.
- High-to-extreme potential for spread.
- High environmental impact.
- High-to-extreme economic impact.
“Despite the great dangers inherent in the myrtle rust invasion of Australia the government committee responsible stood down a federal response and cut funding after just a week, having found only one other infected site,” Mr DeJose said.
“There should be a comprehensive and transparent review of the nation’s response to the myrtle rust incursion. Australia needs to learn from what went wrong with myrtle rust, to consider new threats, make plans to counter them and, most importantly, to fully resource and implement the plans when the need arises.”
Myrtle rust arrived in Victoria in January 2012, having taken less than two years to colonise most of the east coast. It may prove to be one of the most calamitous environmental pests of the century.
Attacking Australia’s dominant plant family (Myrtaceae, of which there are more than 2500 species), it will damage our landscapes, making them less resilient to climate change and may endanger whole species.
“Profound changes to the plant mix in an ecosystem can cause big problems for a range of animal species that depend on them for survival,” said Mr DeJose.
“Our ecosystem health is already in declin (2), largely due to the impacts of invasive species, one of the top three threats to nature in Australia (3).
“Importantly, Australia’s wattles are nitrogen-fixers, a primary source of scarce nitrogen in our ancient, depleted soils. No one knows how severely exotic pathogens might disrupt this essential ecosystem service provided by wattles.
“If we don’t better manage our biosecurity, our children and grandchildren might inherit an environment so poor it can only support a poor society.”
John DeJose, Invasive Species Council CEO – 0433 586 965.
1. ‘Overseas Incubators’, page one of the Feral Herald, issue 27
2. State of the Environment 2011 report.
3. Invasive Species: One of the top three threats to Australian biodiversity.
Image attribution: the photo of a golden wattle on the home page was sourced from Wikipedia under a GNU Free Documentation Licence.