Cool Burning


Australia experienced a terrifying Black Summer in 2019/20, when massive bush fires burned some 35 million acres, destroyed an estimated 3 billion vertebrates (perhaps driving a number to extinction), wrecked scores of irreplaceable rock paintings, wiped out 3000 buildings and, sadly, 47 people died. The tragedy may have cost Australia as much as A$80 billion.

Now research has revealed the cause of this catastrophe. In a work entitled “How 1970s conservation laws turned Australia into a tinderbox” a number of researchers from major academic institutions across Australia and elsewhere have published their findings in MDPI, the largest open-access, peer reviewed publication in the world.

The reason for the ferocity and extent of the fires is now clear. Detailed findings for one of the worst affected areas found that before the 1970s there were fewer bushfires, while after the 1970s they became more prevalent, eventually resulting in the horror of the Black Summer. So, what changed in 1970? The new research demonstrates that the pivot point was legislation, introduced in the 1970s, based on the trendy idea that: 

“Nature should be left to grow freely without human intervention”

It now appears that this legislation, “The Land Conservation Act of 1970” – aimed at “protecting the Australian bush from humans” banned farmers from mimicking the earlier traditional Aboriginal burning practices of using frequent fires to promote grass for livestock. As a result of the ban, the quantity of flammable trees and shrubs expanded, resulting in huge volumes of dry fuel accumulating year on year. It was only after this prohibition on traditional burning that catastrophic bushfires became an issue in the study area.

Originally, like Native Americans, Aboriginals’ Care for Country promoted a safe, productive and predictable environment based on Cultural Burning, also known as “fire ecology” or “Fire-stick farming”, the practice of regularly burning overgrowth to promote the production of fertile grassland. In Aboriginal Australia, it was regulated by strict spiritual, cultural and pragmatic protocols. Until the 1970s, many settler farmers in Australia observed and mimicked this practice of cultural burning, resulting in large swathes of green grassland suitable for livestock. However, after the introduction of some trendy legislation, under pressure from “environmentalists”, pragmatism was replaced by dogma. The result was the uncontrolled growth of eucalyptus forest, a dangerous environmental fuel load, and the tragedy of Australia’s Black Summer.

It is clear that the prohibition on regular burning allowed a vast amount of flammable fuel to build up in the environment, a disaster waiting to happen.

California had a similar problem in 2020, when a combination of climate change and “hands-off nature” politics interfered with traditional management and allowed an accumulation of unburned fuel. The problem there was compounded by the number of housing developments scattered across previous wilderness – any bush fires that broke out were dealt with quickly because of the concerns of residents, but that efficiency also allowed brushwood fuel to accumulate, a problem further compounded by the number of houses and cars that are, unfortunately, also inflammable. Fire doesn’t discriminate.

We face the same danger in the UK, albeit on a far smaller scale but the arguments and effects are just the same. A huge majority of the public have absolutely nothing to do with land management, a lack of knowledge and understanding that leaves a void in the public mind. Political miscreants and fundraisers soon creep into that void, especially when they have financial or political capital to make.

What is the reality in the UK? Could we face a similar situation to Australia?

Huge, uncontrollable wildfires usually occur in hot, dry windy weather, typically hot summers, and why global warming is often blamed, allowing eco-activists to suggest that intentional fires make matters worse and add to the casualties. Regardless of how they are started – lightning, discarded cigarettes or barbecues, arson or by mistake, wildfires soon burn out of control, generate their own up-draught and the results are the dramatic pictures on TV. They move quickly, particularly when resinous or aromatic vegetation is involved, by throwing burning embers high above and far ahead, leaping and burning deep into the soil, destroying animals, plants, seeds and even the microorganisms so vital for soil fertility. They leave the soil sterile and exposed to erosion when rains return. Where wildfires burn intensely over peat soils, the peat may catch alight and burn for a long time, releasing huge amounts of carbon. Wildfires are a disaster in every sense of the word, and should never be confused with controlled burn land management.

Controlled burn, on the other hand, is first and foremost planned, often referred to as “cool burn” and usually performed in the winter, during the period when the underlying soil and peat is cold and wet, allowing the fire to remove unwanted woody growth and accumulated vegetation above without affecting the soil. Done carefully and appropriately, it is said that it can pass over a Mars bar on the ground without affecting it. It is often done in a patchwork rotation of burned and unburned areas and has a huge number of benefits:

Performed in autumn and winter when the soil is cold and wet, cool burn does not affect the soil, the seeds or the microorganisms in the soil below, so vital to the whole system. In winter, it avoids the breeding season of ground nesting birds and at a time when many of the smaller animals, reptiles and insects are safely tucked away underground.  

Performed in strips or a patchwork of rotated areas, it allows mobile wildlife to migrate to adjacent areas until regrowth is established and re-colonisation rapidly takes place. Adjacent burned areas act as firebreaks to prevent uncontrolled summer wildfires – they remove risk and do not add to it. 

One of the two great advantages of cool burn is the reduction of fuel load. Heather, for example, grows woody as it gets older, providing huge amounts of potential fuel that releases massive amounts of stored carbon in a wildfire. Regular controlled burning, while causing a relatively small release of carbon, prevents the production of the old, woody fuel load that burns with such intense, damaging heat in wildfires.

Peat is not affected by controlled cool burning. It is not set alight by controlled burning while it is wet. If anything, it is improved – peat is formed from layers of sphagnum moss, and when more dominant plants grow on peat bogs, they shade and kill the sphagnum. Controlled burning removes the shade cover and allows the sphagnum to recover – the very opposite to the misleading claims by critics of cool burning.  

The other great advantage of controlled burning is the promotion of growth. Controlled burning merely prunes the overgrowth, causing it to re-shoot as the season revolves, rapidly re-taking up and storing carbon. This fresh green growth is the aim of many cultural fire management systems because it attracts animals and birds in large numbers and is well-known to UK land managers, too. Apart from resisting fire, the fresh, tender regrowth provides both food and insects to a large number of smaller mammals and birds too, particularly ground-nesting birds – the reason why faunal biodiversity is so much better on properly managed moors than in so-called “untouched reserves” that are often little better than barren wastelands, disfigured by one or two overgrown dominant plant species that are old, unpalatable and lacking nutrition provide little food except for wildfires. 

Even the unarguable advantage of fresh green food production is not the only advantage – controlled burns turn the unpalatable, woody old growth into fertiliser in the form of ash while the relatively cooler heat and smoke of controlled burns, far from destroying seeds, actually help the seeds of plants called pyrophytes that need fire in order to germinate. Controlled burning is thus a huge help – it removes the dense cover that blocks out light needed for germination and seedling growth and kick-starts the pyrophytic seeds, while providing fertiliser and sanitising the seedbed. This explains the greater plant diversity on properly managed moors and estates. It produces a much-improved, ecologically diverse habitat that is the very opposite of the claims made by critics.

All fires create carbon emissions, but controlled burning creates comparatively little in the long term, preventing the huge amounts produced by wildfires, like the 700,000 tons released by the massive Flow Country wildfire in 2019.       

Critics are keen to suggest that there are better alternatives to burning, like mowing by hand or machine. These are usually claims made by people who have never mowed anything and those who have ideological objections to burning. In reality, many places are steep, rugged places with stone outcrops, making machine mowing impossible, and in any case a recent study has shown that mowing does not produce any savings of carbon emissions. There are occasions when mowing is a better option, such as places where mown heather has a resale value, but as a general rule, burning is far more cost-effective. 

The truly ironic part of this whole argument about controlled burning is the fact that gamekeepers and other active land managers, who do use controlled burning to improve the environment and wildlife, are often the first to respond when fires break out on unattended “hands off” reserves where flammable woody fuel has been allowed to accumulate irresponsibly.  

And so the arguments will go on. In truth, Land Management is a complicated business, and Controlled Burning is a complication within that complication. It will always be difficult to persuade an unknowledgeable public about the realities of controlled burning and it won’t be made any easier now that professional fundraisers and PR wonks have infiltrated NGO’s like the National Trust (once upon a time primarily concerned with the preservation of Britain’s heritage) and the RSPB (once upon a time concerned solely with the plight of the UK’s birds). It is a sad fact that emotional and political campaigns to “protect the environment from humans” rake in far more income than the more mundane reality of heritage or birds can ever achieve. 

John Nash grew up in West Cornwall and was a £10 pom to Johannesburg in the early 1960’s. He started well in construction project management, mainly high-rise buildings but it wasn’t really Africa, so he went bush, prospecting and trading around the murkier bits of the bottom half of the continent. Now retired back in Cornwall among all the other evil old pirates. His interests are still sustainable resources, wildlife management and the utilitarian needs of rural Africa.