Australia — A rare species of gum tree that five years ago faced extinction has been resurrected by one of the most destructive natural disasters in Australia’s history – the Black Saturday bushfires.
While the 2009 fires caused great destruction to lives and property, the flames were a saving grace for the rare Buxton Silver Gum.
Found in only two sites in Australia, both north of Melbourne, a survey of the gums in 2005 found the species was failing to regenerate in the wild. Advertisement: Story continues below
But after the Black Saturday bushfires swept through, razing the 17-hectare Buxton Silver Gum Reserve near Marysville, the gum’s hardy secrets were revealed.
A significant amount of topsoil was burnt in the fires, exposing the tree’s large underground lignotubers – nutrient-rich stems – which were previously unknown because the trees had only been examined above ground.
The Parks Victoria ranger in charge of the Buxton Silver Gum Reserve, Julie Flack, said the discovery pointed to the trees’ longevity.
“That’s an indication that those trees may be many hundreds of years old,” Ms Flack told AAP.
The gums can seed or sprout from the lignotubers, Ms Flack said.
Four months after the fires in June 2009 the gums were sprouting fresh foliage.
The reserve also flooded for the first time in 14 years last September, creating ideal conditions for regeneration.
“What’s become apparent since the 2009 fires is that the fire and flood has absolutely triggered some really good results,” Ms Flack said.
She said it is now known that the species requires fire – and an extremely severe, hot one at that – and flood to survive.
But what it doesn’t need is another fire before the reserve has had time to recuperate.
“We’re hoping the trees will set viable seeds before we have another fire event,” Ms Flack said.
Work is also being done at the reserve between Taggerty and Buxton to control other threats to the gums, including a native parasitic climber, Cassytha, and grazing by rabbits, wombats and wallabies.
“Just to survive is not necessarily good enough, it needs to thrive. That’s why we need to remove the threats,” Ms Flack said.
Further surveys will be carried out next month and in another five years’ time to track the species’ progress.
The Buxton Silver Gum also grows in the wild at Yering, in the Yarra Valley, and is a popular ornamental for gardens.