How does the Australian landscape recover after a bushfire?
Fires burned for days in the Deepwater National Park, yet many native trees will live on. (Supplied: Wayne Rahn)
While the damage caused by last week’s Queensland bushfires is widespread, it may not be all bad news for the landscape.
More than 52,000 hectares of bushland was burnt across central Queensland and many residents only returned to their homes in recent days.
But the future for native trees in the area could be brighter than we think thanks to widespread rain, cooler conditions and fresh ash beds setting the vegetation up for a stable recovery.
Burnt bushland not ‘lost’
Associate Professor Rod Fensham from the University of Queensland said fire could be a good thing for the bush landscape.
“The Australian bush is remarkably resilient to fire and has evolved with it for many millions of years,” he said.
“Some of the reporting that has happened over the last week about hundreds of acres of bushland being lost to fire is not correct, as the land can rejuvenate itself.”
Dr Fensham said native trees, especially eucalyptus forests, had “superb adaptions for recovery and are prime for regeneration”.
“The Australian gum trees carry seeds in their canopies in a hard, wooden capsule,” he told ABC Radio Brisbane’s Craig Zonca and Rebecca Levingston.
“When it burns the rain of seeds is released, and on the back of the first rains, the ash bed left by the fires is the perfect seedbed.
“It’s a new life for many of the species that rely on seed.”
Pods can be harvested at seeds labs like the one at Brisbane’s Botanical Gardens. (ABC Radio Brisbane: Jessica Hinchliffe)
Not only do seed capsules keep the bushland regenerating, but many trees also hold a thick covering of protective bark.
“A lot of Australian plants have remarkable structures that help them remain strong, including lignotubers, which are giant underground woody organs that have rejuvenating buds,” he said.
“Those plants will come up through the ash again and regrow.”
The miracle of rain
Images of Eungella National Park near Mackay have left many local residents worried about the future of the area after the fire.
Dr Fensham said rainforests provided a different kind of fuel compared to bushland, due to the structure of the vegetation that grows within.
“The difference between rainforests and bushland is that rainforests put the fuel up in the canopy instead of on the ground and most fires need to burn from the ground up.
More than 100,000 hectares of the Eungella National Park and surrounds have been charred by fire. (ABC News: Harriet Tatham)
“Generally, rainforest retards fire — as soon as the fire hits the rainforest edge the fire’s extinguished.”
He said issues for rainforests arose when the area had not been burnt for some time.
“The rainforest moves out and the boundary extends so it can be singed and moved back by hot fire,” he explained.
“A lot of the slopes to the rainforest edge are covered by a molasses grass, which is an exotic grass that is full of sugar.
“Sugar burns, so those fires were extremely intense coming up to that rainforest boundary.”
Dr Fensham, who has undertaken extensive ecological research throughout Australia, lost his own property to fires in Victoria in 1983.
“My thoughts are with the people who have lost their properties over this event,” he said.
“If good rain does occur though, then we will see new life and the eucalyptus and grass trees will shoot first.”