Logged forests are at greater risk of severe fires under catastrophic conditions than unlogged forests, regardless of fuel load, according to new research.
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Researcher Dr Brendan Mackey of Griffith University recently led a review of all peer-reviewed studies on bushfires and logging in the eucalypt forests of South East Australia.
He was quick to emphasise that logging does not cause fires, and that in catastrophic conditions, everything will burn.
The data indicates that logged forests, however, will burn more intensely than their un-logged counterparts.
"Big, dangerous fires are driven by weather and climate," Dr Mackey, who has a PhD in ecological science, said.
"The big fires last year were at the back end of a very deep winter drought. There was very dry fuel, which is highly flammable, and then extreme weather conditions that were very hot with strong winds.
"All you need then is ignition."
Dr Mackey said climate change had caused an increase in temperature and reduced winter rainfall in southern Australia. As a result dangerous fire conditions occur more frequently.
"Once you have those conditions, the amount of fuel is not as important as how dry that fuel is," he said.
The review was conducted by the Bushfire Recovery Project - a joint project between Griffith University and the Australian National University to inform the public about what the peer-reviewed science says about bushfires.
It found native forest logging increases the severity at which forests burn, beginning roughly 10 years after logging and continuing at very elevated levels for 30 or more years.
Logging reduces the forest canopy, and allows more light and wind to reach the undergrowth, drying it out.
Slash is often left behind, and adds to the amount of dry fuel.
"The 51 studies we examined all suported those two key findings," Dr Mackey said.
"It's not that logging causes fire, weather and climate causes fire, but when you do have a fire the evidence is that it burns more intensely in a forest that has been logged compared to an un-logged forest or old growth forest."
While this doesn't mean you can let debris build up in your yard - under moderate fire conditions the fuel load becomes more important - it does mean there needs to be a discussion about the increased risk of logged forest in extreme fire conditions.
Dr Mackey said he hoped his team's research would lead to renewed conversations between politicians, government agencies and the community about how best to manage our forests.
"People need to update forest management strategies and plans in accordance with what the latest data is telling us, and my job as a scientist is to make sure people are aware of what that data is," he said.
"It's not my job to tell people what to do, but to share what the literature is telling us. There are different strategies that can work, and those options vary depending on local circumstances."