A small fire at the end of a long walk is one of the great pleasures of British outdoor life. But heathland is among the most fire-sensitive habitats in these islands, and a badly managed campfire can leave a scar that outlasts the memory of the trip. The good news is that a genuinely low-impact fire is not difficult. It simply asks for a little thought before you strike the match, and a good deal of patience when you put it out.

Why heathland fires need extra care

Lowland heath — the heather, gorse and bracken commons of Surrey, Dorset, the New Forest and the Suffolk coast — is rarer globally than tropical rainforest. Britain holds a significant share of what remains, and much of it is protected as a Site of Special Scientific Interest. It is also, by its nature, tinder-dry for much of the summer.

Three things make fire here particularly damaging:

• Peat and root mats. A fire lit on thin heathland soil can smoulder underground for days, creeping unseen through the root layer and flaring up long after you have walked away.
• Gorse and dry bracken. These burn with startling speed and heat. On a breezy day, a modest fire can become a running wildfire in a matter of minutes.
• Ground disturbance. A burnt patch may take years to recover. A freshly built ring of stones scraped from the surrounding ground removes the very microhabitats that invertebrates, reptiles and ground-nesting birds depend on.

None of this means you should never have a fire. It means the bar is set higher here than it is in a damp oak wood.

Decide first: stove, designated pit, or nothing

Before you pack the matches, work out which of three options actually applies to your spot.

• A stove is always the lowest-impact choice. A gas stove leaves no trace at all, and a contained wood-burning stove gives you the atmosphere of a fire without scorching the ground beneath it. Both are welcome on most open-access land where fires are banned.
• An established fire pit is the next best thing. If a campsite, bothy or permitted area already has a ring or a raised metal bowl, use it. Never build a new one, and never enlarge an existing ring by pulling in more stones.
• If there is no permitted place, no fire. Check signage, check the landowner's rules, and check the fire danger rating before you set out. During prolonged dry spells, many areas impose total bans — and those bans exist for good reason.

On most land in the UK you also need the landowner's permission to take firewood at all, so plan to bring your own fuel rather than assuming you can gather it.

Fuel: dead wood only, and not the wood you would most like to pick up

Burn only dead wood that is already lying on the ground and snaps cleanly when you bend it. If it bends rather than snaps, it is too green and will smoke heavily.

Leave standing dead trees and thick fallen branches where they are. They are not litter; they are habitat. Beetles, fungi, lichens, bats and small mammals all depend on deadwood, and it is often scarcer on managed heathland than you would think.

• Never burn peat or cut turf sods. Peat is a vast carbon store and a record of thousands of years. It also smoulders invisibly.
• Bring your own if you can. Kiln-dried logs or lumpwood charcoal bought locally are the kindest option, and they reduce the risk of spreading tree disease between sites.
• Keep it thin. Nothing thicker than your wrist. Thick logs need a long, hot, smokey burn — exactly what you are trying to avoid.
• No accelerants, no paraffin firelighters, no plastic. A couple of dry twigs and a little patience will do the job.

Keep it small, keep it close, keep it short

Aim for a fire no bigger than a dinner plate, with flames no higher than your knee. That is genuinely enough to cook on and to sit round. Feed it little and often rather than building a tower and watching it roar.

Before you light, put a bucket or two of water and a trowel within arm's reach, and clear the immediate area of loose bracken, dry grass and fallen needles. Site the fire well away from overhanging branches, exposed roots, gorse and anything that looks like deep peat.

If it is breezy, don't light it. If the wind gets up while it is burning, put it out. Never leave a fire unattended, even for a few minutes, and plan to have it out within an hour or two rather than letting it burn down while you sleep.

Putting it out properly — the part people rush

Start dousing before the fire has died down. Waiting for it to go out on its own is how most campfire damage begins.

• Drown it. Pour water steadily until the hissing stops. For a small fire, two or three litres is rarely enough; carry eight to ten if you intend to burn anything.
• Stir it. Work the ashes and any remaining charcoal through with a stick or trowel, breaking up the clumps.
• Drown it again. Add more water and stir again. Repeat until there is no steam and no glowing embers.
• Test it with the back of your hand. Hold your hand a hand's width above the ashes. If you cannot keep it there comfortably, it is not out.

Charcoal chunks are the usual culprit. They can hold heat for hours under a layer of grey ash, and a gust of wind later can bring them back to life. When in doubt, do the whole cycle once more.

Restore the ground and leave no trace

Once the ashes are genuinely cold, scatter them thinly across a wide area well away from the burn site, or bag them and take them home. Then put the ground back as you found it. Replace any stones you moved, replace lifted turf, and rake leaf litter and fallen twigs back over the spot so it blends into its surroundings.

Before you walk away, step back ten paces and look at the place you used. There should be no blackened patch, no ring of stones, no half-burnt sticks and no ash pile. On heathland, that discipline matters more than anywhere — the habitat you are protecting is older and rarer than almost anything else you will walk through in Britain.