Why Heathland Management Needs Controlled Burning and Grazing

A landscape shaped by people

Lowland heathland looks wild, but it is anything but natural. The open expanses of ling, bell heather, gorse and bracken that survive in Britain exist because people have grazed, cut, burnt and cropped them for centuries. Without that pressure, birch and pine move in, scrub thickens, and within a few decades you have woodland instead. The UK holds about a fifth of the world's lowland heathland, yet we have lost roughly 80 per cent since the 1800s. What remains is fragmented and almost entirely dependent on active management — which raises awkward questions, because the two traditional tools, controlled burning and livestock grazing, can also do real harm if used carelessly.

Swaling: burning with a purpose

Swaling is the West Country word for the controlled burning of heather, gorse and grass on a rotation. Done well, it is not destruction; it is renewal. Heather becomes woody and leggy as it ages, and its value to wildlife changes with each stage. A patchwork of ages — fresh growth, mid-height heather, taller mature stands — supports far more species than a uniform carpet. Burning on a long rotation, often between ten and twenty years, creates exactly that mosaic.

The benefits are concrete. Bare, warm ground appears after a burn, and that is what nightjars need when they return from Africa in late spring to nest. Woodlarks and stonechats use the open areas, and the flush of new growth feeds livestock and shelters invertebrates. Traditional swaling happens between late autumn and early spring, when the ground is damp, growth has stopped, and the risk of fire escaping is lowest.

Grazing: the quiet architects of the heath

Grazing animals do something fire cannot: they work slowly and unevenly. Cattle, sheep and hardy native ponies nibble selectively, favouring soft grasses and young shrub shoots while leaving taller heather and dense gorse. Their hooves poach the ground and open small patches of bare soil — invaluable for solitary bees, burrowing invertebrates and basking reptiles such as the adder and common lizard. Dung feeds a community of beetles and flies, which in turn feed birds and bats.

Native breeds are usually best: thrifty, hardy, and content on poor vegetation that would not sustain commercial stock. Numbers must stay low, and timing matters, since heavy grazing in spring and summer can flatten nesting habitat and strip nectar plants before they flower. Conservation grazing is a long conversation between the animals, the soil, the weather and the species you are trying to help.

When good management goes too far

Both tools can backfire. Burning on deep peat or wet heath is especially damaging: it kills the peat-forming mosses, dries out the surface, and releases carbon that took thousands of years to accumulate. Rules in England now restrict burning on deep peat, and on many sites cutting or mowing is preferred. Burning too often, or in blocks that are too large, simplifies the habitat and removes the dead wood and leaf litter that invertebrates and hibernating reptiles depend on.

Grazing has its own limits. Too many animals, or grazing at the wrong time of year, can turn heather into grassland, compact the soil and erode the thin, acidic, carbon-rich layers beneath. Graze too little and the heath vanishes under bracken, birch and pine. The sensible approach is site by site: match the intensity of burning and grazing to the soils, the species present and the season, and be prepared to change tack if the results are not what you want.

What gardeners can do next to heathland

If you live near a heath, your garden can be a genuine extension of it. Start with the soil: heathers need acid, free-draining ground, so avoid lime and use peat-free ericaceous compost — peat extraction destroys the very habitat we are trying to protect. Plant native ling and bell heather, and leave a corner to grow rough.

• Keep a patch of bare, sandy ground for basking lizards and ground-nesting bees.
• Leave a log pile and some leaf litter undisturbed over winter.
• Avoid rhododendron, cotoneaster and other escapees that smother heathland.
• Never dump garden waste or light fires on a heath — both are serious hazards.
• Keep dogs on leads from March to July, when ground-nesting birds and young reptiles are most vulnerable.
• Join a local conservation volunteer group; scrub-bashing and bracken-crushing days are short, sociable and satisfying.

Heathland has survived this long because people kept tending it. A little of that attention in your own patch — and a little respect for those doing it on the heath itself — keeps the whole system working.