Several of Australia’s indigenous flora, particularly the native Australian guava plant, are at risk to an invasive disease.
Known as myrtle rust, this fungal disease may soon drive the guava plant to extinction. This isn’t the first we’re hearing about the disease. It first appeared on Australian conversationalists’ radars in 2010 and has since spread to close to 400 host species.
The situation is so dire, a recent study found that over a fifth of the New South Wales and Queensland native guava population is gone, with nearly two-thirds having died back to only roots.
The study, published in the Trends in Ecology and Evolution journal, was the undertaking of Dr Rod Fensham an ecologist at the University of Queensland.
“They are the living dead,” he said in The Guardian. “I’m shocked because I don’t like to see things going extinct.”
Myrtle rust’s arrival in Australia can be traced back to a nursery in South Wales in 2010. The fungus favours the Myrtaceae family of plants, of which Australia boasts over 2000 species.
As a safety policy, environments have planted native Australian guava trees in Toowoomba Regional Council gardens where they will be monitored and hopefully kept safe from the disease.
Awareness about myrtle rust is spreading fast on social media.
Australia’s chief environmental biosecurity officer, Ian Thompson, told The Guardian of the situation, “This research has highlighted the existing and potential impact of myrtle rust on many native species and underlines the importance of working to prevent new diseases entering and establishing in Australia.”
Hard to control
Unfortunately, Dr Fensham says other recent conservation efforts have not been successful, as the myrtle rust produces microscopic spores that are easily carried on the wind, making the disease nearly impossible to contain.
“It is particularly catastrophic for many rainforest species like the native guava, and could change the nature of some of our rainforests.
“People remember native guava being so thick that you couldn’t walk through it – it was once extremely common,” he said.
Fensham warns the loss of the native Australian guava plant is not just a loss for biodiversity, but could prove catastrophic for Australian rainforests. This is because the guava plant is being replaced by the invasive lantana species which he says may “render fire-retardant dry rainforest flammable”.
“The loss of native guava and replacement by lantana will increase the flammability of rainforests,” he said.