How Banning Controlled Burning Increases Fuel Load - Leading to Catastrophic Wildfires
- Rob Beeson
- 2 days ago
- 7 min read
In the summer of 2025, a smouldering campfire in Langdale Forest grew into a 5,000-acre inferno across the North York Moors, a stark reminder that our protected landscapes are becoming tinderboxes.
These events serve as a powerful warning of the increasing threat posed by large, uncontrolled fires. While public concern often focuses on ignition sources, a more fundamental factor is quietly increasing the risk: greater fuel loads.
This article explains how policies designed to protect our moorlands by restricting controlled burning can make them more vulnerable to catastrophic wildfires.
Using scientific evidence and lessons learned from recent fires, we show how preventing small, managed fires can lead to a build-up of vegetation that turns entire landscapes into kindling, resulting in fires that are bigger, hotter, and far more destructive.
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How restrictions can create tinderboxes
Controlled burning, also known as muirburn or prescribed fire, is a traditional land management tool used to remove old, overgrown vegetation in small, carefully managed patches. The primary goal is to regenerate more nutritious plant shoots and create a mosaic of different habitats, which benefits ground-nesting birds and other wildlife.
However, policies are increasingly restricting this practice. In Scotland, the Wildlife Management and Muirburn Act (2024) introduced a more restrictive licensing scheme. Similarly, in England, Natural England has imposed regulations that severely limit how and when vegetation can be managed.
The unintended consequence of these restrictions is the dangerous accumulation of fuel. Without controlled burning or other management, old heather, grasses, and bracken build up year after year. This creates a continuous, dense layer of highly flammable material across the landscape. As one government department warned in 2023, this can turn areas like Dartmoor into a "tinderbox," ready to ignite during a dry spell.
The fuel load trap: why more vegetation means bigger fires
Fuel load, flame length and fire intensity
The relationship between vegetation and fire is simple: more fuel means a bigger fire. The amount of combustible vegetation in an area is known as its "fuel load." A higher fuel load directly leads to more intense wildfires that have taller flames, release more heat, and spread faster, making them far more difficult and dangerous to control.
A comprehensive evidence review by Natural England (NEER155) confirms this fundamental principle, providing "strong evidence that fire severity... is influenced by fuel load and structure." By preventing the regular, low-intensity removal of vegetation, restrictions on controlled burning ensure that when a fire does start, its behaviour is more extreme.
How vegetation age changes fire risk
The age and structure of vegetation are also critical. As heather ages, it becomes tall and woody, accumulating a large mass of dry, dead material within the plant canopy. This old growth is less resilient and highly flammable.
The 2025 wildfire in the North York Moors provides a clear example. The fire spread rapidly through areas with a "high proportion of mature heather," where management restrictions had mandated a long 17-25 year burning cycle. This created ideal conditions for a fast-moving, high-intensity fire.
Mosaic burns and fire breaks
Controlled burning is not just about removing fuel; it is also about creating a fire-resilient landscape. By burning small patches in a rotational pattern, land managers create a 'mosaic' of vegetation at different ages and heights.
Recently burned patches have very little fuel and act as natural firebreaks. When a wildfire reaches one of these areas, it runs out of fuel and either slows down or stops completely. This patchwork landscape breaks up the continuity of dense vegetation, preventing a small fire from becoming a landscape-scale disaster.
The value of this strategy was proven during the Carrbridge and Dava and North York Moors fires, where experienced land managers used "tactical back burning" to create emergency firebreaks and help contain the blaze.
Real-world examples
Case Study: The North York Moors Wildfire (2025)
Location: Fylingdales moor, North York Moors.
Context: The fire spread through an area where Natural England restrictions enforced a long 17-25 year burning cycle. This resulted in high fuel loads of mature, flammable heather.
Outcome: Approximately 5,000 acres burned. The fire's westward spread was only arrested after experienced gamekeepers were called in to create an emergency firebreak using tactical back-burning.
Lesson: The primary lesson identified by those on the ground was stark and simple.
"Fuel loads were too high on the moor" George Winn Darley, Owner of Spaunton Estate, North York Moors
Case Study: The Carrbridge and Dava Wildfires (Scotland, 2025)
Location: Carrbridge and Dava, Scotland.
Response: A total of 101 employees from local rural businesses, including estates and farms, mobilised to fight the fires. Critically, 80 of these individuals had direct experience with controlled burning. They provided essential off-road equipment, including ATVs and fogging units, which were vital for reaching and suppressing the fire in difficult terrain.
Lesson: This event highlighted a dangerous side-effect of restricting controlled burning: the erosion of skills and resources needed to fight wildfires. Several respondents noted that where fuel loads had been managed previously, containment was easier. The response was a testament to a deep well of rural expertise. This vital, self-funded firefighting capacity is at risk of being regulated out of existence.
Case Study: Marsden Moor Wildfires (2019–2021)
Location: Marsden Moor, a rewetted peat-rich upland in the South Pennines.
Context: The National Trust's efforts to rewet Marsden Moor by blocking drainage ditches offered a lesson in the limits of a single-track solution.
Outcome: Despite raising the water table, catastrophic fires in 2019 and 2021 proved that a wet sponge can't stop a fire when it's covered in dry kindling. Fire authorities observed that high fuel loads of dead bracken and grass allowed the fire to spread rapidly across the surface of the rewetted peat. The National Trust now uses mechanical cutting and grazing to create firebreaks.
Lesson: Rewetting peatland is crucial for long-term health, but it does not wildfire-proof a landscape on its own. As one study noted, even very wet bogs can burn in dry weather if there is a significant layer of dry vegetation on the surface.
"Moorland wildfires can rage across vast areas once they take hold, even in areas which have been rewetted, any long vegetation will burn and fuel the flames"
John Queen, headkeeper at Linhope Estate and a member of the Northumberland Fire Group
Case Study: Saddleworth Moor Wildfire (2018)
Location: Saddleworth Moor, Peak District.
Context: This major wildfire started in an area where Natural England policy allowed preventative burns only once every 23 years, allowing a massive fuel load to develop.
Outcome: The fire burned for three weeks, required military assistance, and exposed an estimated 5 million people in the surrounding region to dangerous air pollution.
Lesson: This event is a powerful illustration of the public health consequences that can arise from long-term fuel build-up under highly restrictive management policies.
Common misconceptions
“Doesn’t burning damage peat?”
It is vital to distinguish between a controlled burn and a wildfire.
Controlled burns are skilfully executed 'cool' fires that move quickly across the landscape. They are designed to remove the surface canopy of vegetation while leaving the damp, underlying peat soil unharmed.
Evidence shows that these low-intensity fires can reduce dense heather cover without destroying the important Sphagnum moss layer beneath. Cool burns also convert some of the vegetation into charcoal, a stable form of carbon that resists decomposition and remains locked in the soil.
In stark contrast, a severe wildfire burns with incredible intensity for a long duration. It not only destroys the surface vegetation but can also burn deep into the carbon-rich peat soil itself, releasing carbon that has been stored for centuries. The difference in impact is enormous.
A severe peatland wildfire can release around 96 tonnes of carbon per hectare, mostly from the soil, whereas the heather growing on top only accounts for about 6–13 tonnes per hectare. To put it simply, a severe wildfire burning into the peat can release up to 15 times more carbon from the soil than is stored in all the vegetation on the surface. Policies aimed at protecting the carbon above ground are creating conditions that risk the vast stores held below.
“Why not just cut instead?”
Mechanical cutting is sometimes proposed as an alternative, but it has significant limitations. Firstly, much of the UK's upland terrain is too steep, rocky, or boggy for machinery to access safely or effectively.
Secondly, cutting leaves the dead vegetation, known as "brash", on the ground. This material can dry out extremely quickly and, if a wildfire starts, can act like a "massive bonfire," providing even more readily available fuel for the flames.
Good practice matters
Controlled burning is not an unregulated free-for-all. It is a highly skilled and regulated activity conducted by trained professionals who understand fire behaviour and ecology. To ensure safety and effectiveness, land managers rely on several safeguards:
Strict Weather Windows: Burns are only conducted under very specific conditions, including low wind speed, appropriate temperature, and high humidity, to ensure the fire is controllable and stays cool.
Trained and Experienced Personnel: As demonstrated in the response to the Carrbridge and Dava fires, this work is carried out by experienced gamekeepers and land managers who have undergone formal training.
Careful Planning: Burns are meticulously planned. Firebreaks are cut or created in advance, and the size and location of the burn are chosen to meet specific ecological objectives and minimise risk.
Fire & Rescue Service (FRS) Coordination: Many moorland estates work in partnership with their local FRS, sharing knowledge, conducting joint training exercises, and developing site-specific plans for wildfire response.
When conducted correctly by skilled practitioners, controlled burning is a low-risk and beneficial practice that is essential for maintaining a healthy and resilient landscape.
Key takeaways
Policies that restrict controlled burning are having the opposite of their intended effect. By allowing vegetation to grow unchecked, they are creating landscapes primed for larger, more destructive, and higher-carbon-emitting wildfires.
Restricting controlled burning allows hazardous fuel loads of old, dense vegetation to accumulate across our moorlands.
Higher fuel loads lead directly to more intense, faster-spreading wildfires that are far more difficult and dangerous for firefighters to control.
Consequently, wildfires are becoming larger, more frequent, and more severe, causing greater damage to habitats, releasing vast stores of carbon, and posing a risk to property and people.
A programme of carefully planned and expertly executed controlled burns is a critical and proven tool for reducing wildfire risk and protecting habitats from catastrophic damage.
The science of fire is unforgiving. Fuel will always burn. The choice is not if our moorlands experience fire, but how. We can choose a future of small, controlled burns managed by skilled hands, or we can choose a future of catastrophic, carbon-releasing wildfires fought by overwhelmed emergency services. Current policy is unintentionally choosing the latter.
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