Moorland managers say "if, not when" for unstoppable wild-fires as debate over controlled burning rages on

In May 2021 Natural England (NE) banned burning on deep peat in designated sites and on huge areas of other moorland burning over deep peat has been voluntarily discontinued in line with the trend for light-touch management.

The Game and Wildlife Conservation Trust says that as a result, the firebreak effect of a patchwork of controlled burns has been dramatically reduced, heather has grown tall, bracken has encroached, and birch scrub is beginning to take hold, all contributing to a massive build-up of combustible material.

A new report, "Peak District National Park – Wildfire Risk Assessment 2022”, commissioned by the National Park Authority, reveals the chances of wildfire getting out of control are increasing.

Co-author Anthony Barber-Lomax, former resident agent at Fitzwilliam Wentworth Estate, which manages Bradfield Moor in the North Peak, said: “The modelling revealed that without intervention to mitigate the risk, the fuel load is such that a blaze could become uncontrollable over a huge area. It’s not a case of if, but when.”

Unlike the controlled burns carried out by moorland managers, which burn the surface vegetation leaving the moss layer intact, wildfires can burn for long periods and destroy the underlying peat causing a huge release of carbon and risk of widespread damage to human health in surrounding areas.

In 2018, the blaze on Saddleworth Moor in the Peak District affected 2,400 acres with a loss of 40,000 tonnes of CO2 at an estimated cost of £8.76m. But these events could pale in comparison with future wildfires according to the report which predicts that a blaze beyond 3.4m flame length with a rate of spread of 800m/hour is impossible for fire crews to control and yet there is potential for flame lengths up to 7.6m and rates of spread 2,393m/hour.

Habitat managers are aware of the risk as they regularly volunteer to assist the fire service in fighting moorland wildfires. Headkeeper on the Fitzwilliam Wentworth estate Nick Gardner believes heather cutting and rewetting have limitations as ways of mitigating wildfire risk, and he would like to see managed burns on deep peat reinstated.

He said: “We need all the tools in the box. There is a problem with cutting, if the brash is left on the surface. Rewetting is definitely not enough on its own. Some of the boggier areas may be wet and wildfire won’t burn into the peat, but the surface vegetation will still burn, so the fire will travel through those areas.”

NE banned burning on deep peat on the grounds it is damaging to peatland formation and habitat condition and that managed burns release more carbon than alternatives such as rewetting, cutting or ending vegetation management.

Andreas Heinemeyer, Associate Professor of Environmental Research at the University of York, has undertaken a 10-year study comparing the carbon budgets of the different approaches.

Speaking at an uplands management workshop organised by GWCT, the Moorland Association and Fitzwilliam Wentworth Estate, he said: “Certainly, over 10 years, it looks like burning does not have the anticipated large carbon loss, particularly when you add charcoal production into the process, which is a long-term carbon store. The other alternative to cutting is just letting it grow, but you will get a build-up of fuel and large amounts of biomass transpire a lot of water, potentially drying out the peat beneath. We need to have an adaptive management approach because we don’t have the scientific evidence that burning is always bad, that cutting is always better, or that doing nothing will achieve what we want.”