News Daily


The Times Real Estate

Australia

  • Written by The Conversation
New research reveals how forests reduce their own bushfire risk, if they're left alone

Fire management in Australia is approaching crisis point. Seasons such as the Black Summer three years ago showed how our best efforts in fire-fighting and prescribed burning are insignificant in the face of a changing climate.

But what if forests have their own tools to manage bushfire risk, and we could tap into them?

We know long-unburnt mountain forests in south-east Australia are far less fire-prone than more recently burnt areas. And forests in south-west Australia have the lowest fire risk when they’ve not been subjected to prescribed burning.

Our study just published set out to understand why this occurs, by modelling fire behaviour in iconic red tingle forests of south-west Australia. Our findings offer a clear set of tools for living with fire, even in a warming climate.

Smoke billows from forested mountain
The findings offer a tool for living with fire in Australia. Ralph Hurst-Meyers

The ‘fuel load’ dilemma

Most bushfires in the south-west forests of Western Australia occur in areas burned specifically to reduce fuel loads.

Current fire management by government agencies focuses on broadscale burning to reduce fuel load. The practice is also known as prescribed, planned, controlled or hazard-reduction burning. It aims to reduce the intensity of future fires at a location by burning leaf litter and other fine surface matter.

Fuel-load reduction is premised on the idea that the amount of fuel in a forest determines how flammable it is. The idea comes from early attempts at fire behaviour modelling imported from the United States in the 1960s.

But more recent work has shown prescribed burning can lead to catastrophic outcomes. This includes the near-destruction of critically endangered wildlife populations and the destruction of homes when prescribed burns escape.

So what can be done? Our study on the iconic red tingle (Eucalyptus jacksonii) deals with this dilemma.

Read more: Bad fire science can kill our threatened species. It's time to cooperate with nature

Prescribed burns aim to reduce the intensity of future fires. WA Department of Parks and Wildlife

Getting to know the red tingle

Red tingles are among the tallest eucalypts, growing up to 70 metres. They grow only in a 6,000-hectare stretch along the high-rainfall south coast of Western Australia.

Red tingles can live for more than 400 years. They regenerate well after fire – even an intense fire – and form naturally mixed aged forests dominated by large old trees.

But red tingles are sensitive to frequent fires, no matter how mild. Flames can enter the tree and hollow it out, eventually causing its collapse.

a large tree, left, and a collapsed tree after fire, right
Left: A red tingle tree. Right, a collapsed red tingle after repeated fire. M Howe

The understorey of red tingle forest consists of tall, long-lived shrubs that germinate prolifically after fire. These understoreys thin and open as they age.

The goal of our research was to understand how these changes in red tingle forests affect fire behaviour. To do this, we used an advanced fire modelling tool developed by the lead author of this article, Phillip Zylstra, and his colleagues.

The tool doesn’t use a simple number to characterise a forest’s fuel load. Instead, it uses hundreds of thousands of calculations to determine which plants will ignite – and importantly, which plants won’t ignite but will instead calm the flames.

So what did we find? As the understorey of red tingle forest ages and thins, the lower branches of taller plants “self-prune” – in other words, they shed dead leaves and twigs.

When this litter is on the ground, it begins to decay and poses a lower fire risk than if it were still suspended.

The lower branches of taller plants, once self-pruned, are then less likely to ignite as fuel. Instead, they act as “overstorey shelter” that reduces wind speed and fire severity. In this way, mature forests control fire rather than drive it.

Our study showed that, due to this calming effect, fires in mature red tingle forests could be extinguished by firefighters most of the time.

By contrast, our study showed that prescribed burning in red tingle forests creates dense regrowth, which burns severely during bushfires. In such cases, our study showed firefighters are often unable to extinguish the flames and must resort to backburning - a risky fire suppression technique.

Read more: New modelling on bushfires shows how they really burn through an area

left to right, a burnt tree, a regrowth forest and a mature forest Left to right, a red tingle forest after a prescribed burn, the resulting regrowth, and mature forest. M Howe; P Zylstra

Making peace with the bush

Contemporary fire management approaches, and their dependence upon broadscale prescribed burns, contrast starkly with the approach of Australia’s First Nations people.

Menang and Goreng Traditional Owners of red tingle and surrounding forests say fire should be used in specific locations, burning only what is needed in small, strategically placed patches. Wadandi Pibulmun Yunungjarlu Elder Wayne Webb advised our team that Traditional Owners deliberately excluded fire from tall red tingle forests.

In our contemporary context, we can co-operate with the landscape - balancing the effects of climate change by using specialist fire-fighting skills and technological advances to reinforce safe forest havens.

The fire risk in WA’s south-western forests, and many other eucalypt forests, is so much lower if they’re left unburnt and allowed to mature. Our analysis of red tingle forests helps explain why.

One thing is clear: if we still want forests in our flammable country, we must stop burning their defences away.

Read more: Contrary to common belief, some forests get more fire-resistant with age

Read more https://theconversation.com/new-research-reveals-how-forests-reduce-their-own-bushfire-risk-if-theyre-left-alone-201868

Top 5 Providers of SEO Focused Guest Posts in Florida You Can Trust

Many companies today aim to increase their online presence, which is a good use for guest blogging. In guest blogging, you compose content for the benefit of other websites that link back to yours. This promotes your business and increases... Read more

The Role of Litigation Lawyers in Brisbane

Litigation lawyers in Brisbane play a crucial role in the legal landscape, ensuring justice is accessible and efficiently administered for the clients they represent. They have expertise in handling disputes that may result in court proceedings, with their work encompassing... Read more

Edge Computing: Revolutionising Connectivity in the Digital Age

Edge computing is rapidly transforming how organisations process and manage data, bringing computational power closer to where it's most needed. In an increasingly connected world, Microsoft Azure services are at the forefront of this technological revolution, enabling businesses to leverage... Read more

What You Need to Know About Towing a Caravan

Towing a caravan can be an exciting way to explore Australia's vast landscapes, but it also comes with its own set of challenges. Whether you’ve just purchased a new caravan or are browsing caravans for sale, understanding the ins and... Read more

How to curb short-sightedness in kids

Kids should play outside more to reduce the risk of short-sightedness and potential adult blindnessWe are in the grips of a ‘myopia epidemic’: more than 20 per cent of Australians have myopia or short-sightedness, tipped to rise to 50 per... Read more

The Importance of Fast Energy Services in Your New House

Moving to a new place is challenging and accompanies a lot of work. From packing to getting everything to your new place and unpacking, there’s alot to consider. One important necessity people forget to check is if the electricity and... Read more