Swaling is a traditional management technique that has taken place for hundreds of years. It helps prevent gorse and scrub from dominating the landscape and keeps moorland habitats open. Removing older vegetation encourages fresh shoots to develop and creates areas of bare soil. These young shoots provide valuable grazing for livestock and wildlife, while bare ground offers opportunities for wildflower seeds to germinate and provides foraging and nesting habitat for many invertebrates.

Burning small, carefully managed patches also creates a mosaic of vegetation at different stages of growth. This patchwork of young and older vegetation supports a wider range of habitats and species across the landscape.

Swaling is occasionally used at our nature reserves across Cornwall, working with the local community and fire brigade to ensure it’s done safely and responsibly. If we carry out swaling, it is of small, controlled patches at the correct time of year, calculated to avoid disturbance to wildlife and away from fences and private property.

Winter burns encourage a quick flash burn which doesn’t penetrate deep into the ground as the soil is wet. Fewer species are active at this time of year and so are less likely to be at risk. While swaling is generally allowed between 1st November and 31st March across the UK, Cornwall's milder climate means spring often arrives a little earlier than the rest of the country. With species such as adders and grass snakes coming out of hibernation, and birds such as skylarks and meadow pipits nesting on the ground earlier than their counterparts in the rest of the UK, controlled burning of vegetation is generally avoided by Cornwall Wildlife Trust in March.

Potential drawbacks

Carbon emissions - Burning vegetation releases carbon dioxide into the atmosphere. This greenhouse gas contributes to climate change, so the emissions linked to controlled burning remain a concern in a climate-conscious world, even when programmes are carefully managed.

Impacts on wildlife - Controlled burns are usually scheduled outside key breeding seasons. Even so, fire can still disturb wildlife or force animals to move elsewhere. Species that nest on the ground can be especially vulnerable, along with insects and reptiles that rely on vegetation for shelter.

Soil health and erosion - High temperatures during burning can affect the top layer of soil. This may reduce soil fertility and increase the risk of erosion. Over time, these changes could influence how resilient the landscape is to weather and other pressures.

Risk of fires spreading - Although strict precautions are taken, there is always a chance that a controlled burn could spread beyond the intended area. This risk can increase during periods of unusually dry weather.

Impact on peatland - Burning on peatlands may can increase dominance of drier vegetation communities, affect water quality and alter the functional and physical characteristics of the landscape. Burning on peat deeper than 30cm is unlawful unless carried out under the terms of a licence issued by the Secretary of State.

Safety Considerations

When you burn heather and grass you must:

· start burning between sunrise and sunset

· have enough people and equipment to control the burn

· take all reasonable precautions to prevent injury to people and damage to the surrounding land and wildlife

When burning you must not:

· cause injury, interruption or danger to road users

· create smoke likely to damage human health or cause a nuisance

· disturb or destroy wild birds and their nests, or other protected animals, plants and habitats

· damage important monuments

· pollute watercourses and groundwater, for example through soil erosion caused by burning

Wildlife at Risk

In recent years, some of our reserves have been subject to unplanned fire outbreaks, having a detrimental effect on the important wildlife that call these reserves home and destroying years of carefully planned habitat restoration. For example, adders, common lizards, field mice, and ground-nesting birds, including skylarks and meadow pipits, were all likely victims of a fire set at Rosenannon Downs in 2025.

If you're out exploring any of our nature reserves and notice anything suspicious or out of the ordinary that could be a potential fire risk, please let our team know on 01872 273939.