The A to Z of prescribed burning

Do you live in an area where prescribed burns are carried out, but you’re not sure what’s going on? Or do you worry when you hear of one because it’s close to someone you know, and you want to make sure they’re safe?

Maybe having a better understanding of how a prescribed burn is planned for and carried out will put your mind at ease.

We know that prescribed burns help minimise the risk and impact of bushfires by reducing fuel loads in at-risk areas, and that they can be used to maintain or enhance the environment. But they’re not the only tool. NPWS staff also use machinery to remove vegetation (such as slashing) and a chemical knockdown (such as weed spraying).

But what are the ins and outs of prescribed burns? What’s the goal? Is your house being protected? What about the local bandicoot population?

Prescribed burning in South Australia involves targeted and careful preparation from the planning of the burn all the way through to monitoring how the area recovers after the burn.

Working out the land management goal is the first piece in the puzzle for skilled NPWS fire management staff: why does a certain parcel of land need to be protected? And how? Fire management zones help provide the answer.

All NPWS land is assessed to see if a particular fire management zone is required. Understanding the A to Z of these zones can help you understand why our fire crews do what they do.

A is for asset protection

Your life, your safety, and protecting assets are front of mind for fire crews. Assets can be people, buildings or environmental assets like a special piece of habitat. So, if your property is positioned next to a national park or other public land, a narrow section of that land – between 40 metres and 100m – might be classified as an A-zone.

A prescribed burn may be used on vegetation in that A-zone to minimise bushfire risks to nearby assets. The aim is to provide a buffer from radiant heat damage, flame contact and embers.

Property next to an A-zone is given the highest level of protection which is why this zone attracts the most intensive bushfire protection strategy. Over time, when vegetation grows back to a potentially risky level, another prescribed burn is carried out.

B is for bushfire buffers

Buffer zones can be anywhere between 40m and 1 kilometre wide. They are burnt to complement an A-zone or reduce the fire intensity of a potential bushfire and its rate of spread. Managing this zone with a prescribed burn makes it easier for crews to supress any bushfires because of the reduced fire intensity in that zone.

C is for conservation and land management

C-zones manage native ecosystems using ecological burns to help maintain or enhance them. These burns are intended to create a variety of habitat for species, particularly for threatened plants and animals, and to reduce weed populations.

Using a prescribed burn for weed management can help achieve the conservation objectives of a park, such as to regenerate habitat for certain birds or animals.

E is for exclusion zones

These zones let staff know where to exclude burns. They are generally in place to protect important plants, animals and cultural sites. The status of an exclusion zone is reconsidered whenever a fire management plan is reviewed.

S is for strategic fuel management zones

S-zones also aim to reduce bushfire risk to life, property and environmental assets by slowing the rate of spread and intensity of bushfires and providing strategic suppression opportunities. However, they don’t require vegetation to be maintained below a specific amount. And not all areas need treating to meet the zone’s objective. This allows pockets of habitat to remain untreated.

The intent is to work within the zone using existing landscape features like wet areas, dunes and fire scars to shape prescribed burns, or to allow room for a mosaic of different age classes over time. The planning of these zones also considers opportunities to maintain and enhance environmental values.

U is for unzoned areas

These areas are not defined by a zone, nor managed for a particular fuel reduction or fire management objective. That’s because fire management strategies are determined by assessing risk and environmental values. If areas are not identified during these assessments, or if adjacent strategies address the risk or values, then additional strategies are not needed.

Learn more and discover how prescribed burns renew wildlife habitat and why prescribed burns are important in managing national parks.

The expertise for this highly skilled work resides in the South Australian Department for Environment and Water (DEW). DEW is also a brigade of the Country Fire Service.

Main image: Map showing proposed fire management zones in Cleland National Park, near Crafers, to reduce bushfire risks and manage ecological values