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The Howitt Society, Victoria’s equivalent of the Bushfire Front in WA, is equally strong in advocating the benefits of prescribed burning. Here is an article from their latest newsletter on the role of fuel reduction burning, with excellent examples from their “Black Summer” bushfires. We support the Howitt Society in their endeavours to influence public thinking in Victoria. We kindly thank them for sharing the following.

Educating the community

For the Howitt Society to be successful in achieving the goal of improved land management we need to be part of the process to better educate the public on the issues of concern with respect to current land management practices.

The role of Fuel Reduction Burning in Fire management

After any fire season there are many examples in the media of personnel associated with State fire suppression agencies, as well as academics, putting forward their theories concerning the role of fuel reduction burning.  Their theme has been “fuel reduction burning did not stop the bushfires, so it is of no use in fire management”.

These comments have been made by people with apparently little no understanding or operational experience of bushfire behavior, prescribed burning and bushfire suppression. These critics include academics who dabble in fire management from their ivory towers. Very few of them know anything at all about the realities of bush fire management. Their baseless opinions, if given credibility, will give rise to very dangerous bushfire management policies, a continuation of an increasing cycle of devastating bushfires and further losses of lives, properties and beautiful forests.

Prescribed burning is not designed to stop wildfires. It is designed to make them easier, safer and cheaper to suppress. Experienced land managers, fire fighters, and the bushfire scientists who work closely with them, are in no doubt that the scientific, experiential and historical evidence demonstrates that prescribed burning, done properly, is highly effective at mitigating the bushfire threat, even under severe weather conditions.

The case for a broad scale fuel reduction burning (FRB) program

  1. Fuel loading in a forest is the only component of fire that can be modified by land managers.
  2. No fuel = no fire, less fuel = lower fire intensity.
  3. The goal of a Fuel Reduction Burning (FRB) program is not to stop fires.  That would only be possible if all fuel was totally removed from all areas (no fuel = no fire).  The goal of a broad scale FRB program is to create a mosaic of burnt and unburnt areas of various ages and reduce the intensity of the inevitable wild fires.
  4. FRB can be targeted at areas where fires are most likely to ignite – eg on ridge tops, dry northern slopes.
  5. Broad scale FRB across the landscape will reduce the incidence of long distance spotting which occurs when fire intensity becomes extreme.
  6. Lower fuel quantities mean that when a fire does start it burns less intensely and it is more likely to be contained at the first attack stage – see photo 1.
  7. FRBs are planned to be slower and patchier than a bushfire. Not all of the vegetation on the ground is burnt and the upper parts of the trees are largely unburnt. This makes it easier for animals to escape the flames and provides habitat immediately after the fire. Due to the lower intensity of fuel reduction burning relatively low levels of smoke and embers are generated in comparison to a bushfire.
  8. A large scale FRB program creates a mosaic of burnt and unburnt country of different ages which is important for species survival.  This is in stark comparison to mega fires as seen in 2019/20 (photo 6) which burn millions of hectares at the same time threatening the extinction of species.
  9. FRBs burn the fibrous bark on trees and make them less prone to spotting during a wildfire event – see photos 2 and 5.

Photo 1 – Corringle Rd area south of Orbost 31 December 2019.  Spot fire about 15 km in front of the main head fire which was burning under extreme conditions (see photo 3)  Spot fire was into an area which was fuel reduced  4 year ago.  Fire was easily contained with a dozer line

 Photo 2 – Coastal forest south of Princes Hwy near Orbost.  Area fuel reduced 4 year ago.  Note the light ground fuels and the  fibrous bark which contributes to spotting has been charred

  1. Creating a mosaic of burnt and unburnt areas across the landscape gives a strategic advantage to fire controllers when there are multiple fires in the landscape.  Those in recently burnt areas can have delayed first attack so that the controller can focus on the priorities.
  2. Recovery time for plants, animals and habitats after low intensity FRBs is much quicker than after high intensity bushfire.

Responses to the arguments against a broad scale fuel reduction burning program

There are a range of arguments put forward against a broad scale fuel reduction burning program.  Some of them are listed below along with commentary and response.

Argument 1 – FRB does not stop wild fires

Much of the debate around the effectiveness of FRB revolves around the fact that many areas which have been subjected to FRB in recent years have burnt again in wildfires. In many cases the statement is true.  However the goal of a FRB program is not to stop fires, that would only be possible if all fuel was totally removed (no fuel = no fire).  The goal of a broad scale FRB program is to reduce the intensity of the inevitable wild fires and assist fire fighters to control them before they become mega fires and minimise the damage to the environment.

A one year old FRB can stop an intense wildfire –see photo 3

Photo 3 – Painted Line Link Tk north of Waygara – main fire front burning from NW (bottom right) on 31 December 2019 stopped by April 2019 fuel reduction burn – some scorch to vegetation in fuel reduced area for about 20 metres

A two or three year old FRB can either stop a wildfire or change its characteristics from crown fire to ground fire – see photo 4

The key issue following a FRB in an area is the lower intensity of any subsequent wildfire, the lesser impacts on the environment and the ability to control the fire.

The impact of wildfire on an area which has been subjected to FRB will depend on how long since the FRB was conducted and what proportion of fuel was removed during the FRB.   In some fuel types the FRB has an impact on fire behaviour for many more years – see photos 1 and 2.

Photo 4 – 41/2 Mile Track north of Orbost – main fire front burning from NW (top left) on 31 December 2019 stopped by two year old fuel reduction burn – some ground fuel burnt again in FRB area

The opponents of fuel reduction burning fail to realise the operational difficulty of fighting a wildfire in extreme conditions. The only option or tool that the land manager has available is the manipulation of fuel in the fire triangle (heat/ignition, air, fuel). There is no question that on extreme fire days fire control personnel would not attempt a direct attack in areas with heavy fuel loads. Even in a fuel reduced area, on extreme days there is no question that fires would burn through those fuels as well, but the moderating effect of that fuel reduction activity is quite profound and is very useful in assisting fire control personnel in the periods of the day when those extreme fire behaviours wane.

To state that one individual FRB failed because a fire spotted over it or burnt through it demonstrates a lack of understanding of the science of a broad mosaic of burnt and unburnt areas.

Many houses burn in open paddocks from flying embers that can travel through the air for kilometres. Fires need to be high intensity to create the updraft for these long distant spotting events to occur.  Fuel load is an important determinant of creating the fire intensity needed.  So if there is a mosaic of burnt and unburnt forest it is likely that there will be less intense fire behaviours and less long distant spotting.

Argument 2 – The window of opportunity to burn is becoming shorter because of changes in climate

Whilst changed temperature and climate conditions may/will reduce the ‘windows” to carry out FRBs around traditional and historical seasons, they will also open up opportunities to burn into late autumn and winter.

Whilst it is recognised that in some years weather conditions are not optimal for FRB operations this should not be an excuse to not burn.  What is required is adaption to the changing circumstances.  For instance :

  • Retain summer fire crews into the autumn and early winter to provide the necessary labour.
  • Burn into the evenings instead of during “normal” working hours when weather conditions are too hot.
  • Burn later into the season.
  • Burn through the winter in some locations – particularly ridge tops and road edges.
  • Incorporate a multi stage burning approach for large burn units  ie burn ridges and North and West slopes late autumn and South and East slopes early season

There is normally an opportunity for a fuel reduction burning program to be carried out if the land manager has allocated adequate planning and resources to the program and is opportunist in application of the plan.

Argument 3 – Some fuel reduction burns “get away” and do damage

The balance for when it is safe to conduct a FRB is a fine one between hot and dry enough for fuels to burn but not so hot and dry that fire is likely to get out of control.     Good science and good planning usually get the balance right. However when dealing with natural systems it is possible for an unexpected change in conditions and a FRB may break from its planned boundaries. The possibility of a breakaway is part of the planning for a FRB and when something does go wrong all the equipment and resources are on site to deal with it and the damage caused is usually insignificant.

In rare cases there is more significant damage from a breakaway (eg Lancefield, Wilsons Promontory) and the media report it as though it is the normal outcome rather than an aberration.  These instances lead to a more risk averse approach by government.  This is an issue which needs to be addressed and there needs to be support for those carrying out a difficult community service.  Whilst such damage is regrettable it is insignificant compared with the damage from large high intensity uncontrolled wildfire.

Argument 4 – FRB kills birds and animals

Fuel reduction burns are planned to be slower and patchier than a bushfire. Not all of the vegetation on the ground is burnt and the upper parts of the trees are largely unburnt. This makes it easier for animals to escape the flames, and provides habitat immediately after the fire. Due to the lower intensity of fuel reduction burning relatively low levels of smoke and embers are generated in comparison to a bushfire.

A cool FRB will burn about 70% of the area leaving unburnt refuge areas for wildlife – photo 5 as compared with wildfire – photo 6.

Photo 5 – Recent fuel reduction burn – crowns intact and patches unburnt over the planned area

Photo 6 – Recent wildfire – 100% burnt including crowns.  No remaining habitat

 Argument 5 FRB in recent years have been too hot and have caused damage to the environment

Some FRBs in recent years have been hotter than planned.   This is often due to aiming for the FRB to remove all the long term fuel load in one burn rather than a staged approach.  It is also due in part to the staff not adapting to two factors :

  • The available fuel for the FRB in recent years is the normal fine fuels (leaves and twigs) but also much of the heavy fuel (branches and logs) due to the drought conditions.
  • Drier burning conditions.

Both of these factors require an adaptive approach when burning takes place – later in the day, later in the season, multi stage burning or changed lighting patterns.   Regardless of the fact that some FRBs may have been too hot in recent years :

  • They have played a significant role in protecting communities.
  • They do not burn the gully systems so there is still protection of riverine ecosystems.
  • They do not burn the duff layer as intense wildfires do.
  • They do not burn 100% of the area so there are still islands for wildlife etc.
  • In comparison, the alternative is a large high intensity uncontrolled wildfire possibly with a crown fire burning 100% of  everything.

It should be noted that when an area is burnt by a large mega fire, any recent FRB area  (even if it was hotter than planned ) becomes the only green refuge for wildlife.  There are numerous examples of this in East Gippsland following the recent fires – see photo 7 as an example.

 

Photo 7 – Princes Hwy at McKenzie River (between Orbost and Cann River) looking west.  Main fire front burning from the NW (top right) burnt all bush in the area except the area on the right which was fuel reduced two years ago.  It is the only remaining green bush in the locality

Argument 6 – Areas subject to an FRB will burn again

Those who use this argument against a broad scale FRB program do not understand the intent of the program which is to set up a mosaic of burnt and unburnt country of varying ages to reduce fire intensity and rate of spread and to assist in the fire suppression operations.

A very recent FRB cannot burn again (no fuel= no fire). – see photo 3.  However fuel will build up over the years following a FRB and the area will burn again.  The issue is at what intensity it will burn. For instance if an unburnt bush carries 12 tonne/hectare of available fuel and an adjacent area recently subjected to a FRB has built up to 4 tonne per hectare then the recently burnt area will burn at one ninth the intensity of the unburnt area.  This will almost certainly ensure that there will not be a crown fire and the subsequent ground fire will be controllable with ground resources.

The key is that the fire is less intense and hence environmental damage is lessened.

Argument 7 – FRB causes smoke which may cause health issues and is annoying

It cannot be argued that FRB operations do not generate smoke over a period of days or weeks depending on atmospheric conditions.  However there is a relatively low level of smoke and embers generated in comparison to a bushfire burning over a period of months as has  occurred during mega fires.

The smoke from a FRB can be controlled to some extent by when burns are planned and the anticipated weather conditions as compared with the intense smoke from wildfire which is uncontrolled and unplanned in area and time.

Argument 8 – FRB causes species extinctions

Diversity of habitat is the most important factor in ensuring the survival of species.   A broad scale FRB program creates a mosaic of burnt and unburnt forest with varying ages since burn.  The diverse range of habitats that this creates is an aid to species survival particularly in comparison to the impacts of mega fires which burn 100% of large tracts of habitat and remove all diversity.

Many research projects have provided no evidence of loss of a components of diversity through FRB.  Research indicates that FRB certainly can change the species abundance on some sites but no species have been recorded as becoming extinct due to FRB.

Discussion

A broad scale fuel reduction burning program is not designed to stop wildfires.  The purpose is to make them easier and safer to control and to reduce their impact on the environment and communities and their assets.

Reducing fuels works with nature rather than trying to control nature.  The natural scheme of fuel management was regular burning of the vegetation through lightning strikes (and aboriginal burning) which created a mosaic of burnt and unburnt land.  Therefore when a wildfire occurred under extreme conditions its forward progress was slowed and the environmental damage was limited.  A broad scale FRB program seeks to duplicate this outcome.

To be effective, a FRB program needs to be across the landscape and burn between 5% and 10% of the landscape each year.

Opposition to fuel reduction burning ignores the difficulty of fighting wildfire in extreme conditions. The only option available to land managers within the fire triangle is the manipulation of fuel loads. In extreme wildfire conditions a direct attack is futile and this can also be the case in areas where there have been FRBs, however the moderating effect of fuel reduction activity is profound, and is very important during periods of the day when extreme fire behaviors wane. FRBs across the landscape allow land managers greater flexibility and more options to suppress wildfire.

Summary

Land managers have a choice. They can continue with the current policies and at regular intervals have large intense fires with the resulting loss of life, assets and ecosystems or they can work with nature and reduce fuel loads over large areas of the forest.

The irony is that to refuse to burn large areas of forest in a mosaic planned manner eventually results in the destruction of whole ecosystems and loss of life and assets in massive uncontrolled infernos. In recent history land managers have allowed this to occur over and over again.

If land managers do not try to modify fuels to change fire outcomes then what are they going to do?  To continue with the status quo is to accept more of the same outcomes with the same impacts on communities, community assets and the environment.

Land managers need to act because more of the same is not acceptable.

 

THE HOWITT SOCIETY 

Email : thehowittsocietyinc@gmail.com

Website : thehowittsociety.com

Postal address : PO Box 447, Orbost 3888

NEWSLETTER #8 – 27 May 2021

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