Dig a Dakota fire hole

A Dakota fire hole is two connected holes: a fire chamber and an air intake. Air is drawn down the intake, across the base of the fire, and up through the chamber. The result burns hotter and cleaner than an open fire on the same wood, and the flame sits below ground level where it cannot be seen from any distance.

It is the same physics as the rocket stove, built from a hole instead of a stove.

What it is for

Concealment, primarily. The playbook's protection chapters make the point repeatedly that the household that visibly has resources becomes the household people come to. A cooking fire is one of the most visible signals there is: flame at night, smoke by day, and the smell for a considerable distance.

A Dakota hole does not eliminate that but reduces it substantially:

• The flame is below ground and effectively invisible from any distance or angle.
• It burns hot and clean, so it produces far less smoke than an open fire, particularly once established.
• It leaves almost no trace when properly filled in.

Its other genuine advantages:

• Wind resistance. An open fire in wind is miserable and wasteful. A Dakota hole is unaffected, and in fact draws better in a breeze.
• Fuel efficiency. Similar to a rocket stove: small wood, burned completely.
• Stable cooking surface. Lay a grill or two green sticks across the chamber mouth and you have a solid hob.
• Low fire spread risk, since the fire is contained below ground level.

The disadvantages are real too: it takes twenty minutes and a digging tool to build, it gives you almost no radiant warmth (the heat goes straight up), and you cannot sit round it. It is a cooking fire, not a warming fire.

Digging it

1. Choose the spot. Away from tree roots, away from overhanging branches, and on ground you are content to disturb.
2. Cut and keep the turf. Slice a square of turf cleanly, lift it in one or two pieces, and set it aside grass-side up somewhere shaded. This is what makes the fire leave no trace. Keep it damp if it will be some hours.
3. Dig the fire chamber, about 30 cm across and 30 to 45 cm deep. Undercut it slightly so it is a little wider at the bottom.
4. Dig the intake. Start about 30 cm away on the upwind side, and dig down at roughly 45 degrees until you break through into the base of the chamber.
5. Clear the connection. The tunnel must be fully open at the bottom. This joint is the whole design; a partly collapsed one gives you a smoky hole in the ground.
6. Pile the spoil neatly on a sheet or in a bag if you can, both to fill it back cleanly and because a heap of fresh earth is itself a sign someone was here.

Angling the intake into the prevailing wind improves the draught noticeably.

Running it

• Light it in the chamber, small tinder first, then feed kindling down. Once the fire is established the draught takes over and it will roar quietly.
• Feed small wood, thumb-thick, straight down into the chamber. It eats twigs and small splits, exactly like a rocket stove, and does badly on logs.
• Cook across the chamber mouth: a grill, a metal sheet, two green hardwood sticks, or a pan sat directly on the rim if the hole is sized to it.
• Expect very little radiant heat. All the energy goes up through the chamber mouth. Good for a pot, useless for warming your hands.
• Feed it steadily. Like any high-draught fire it burns fast and clean and will go out if neglected.

For a longer burn, dig the chamber slightly larger and bank the fire with a couple of larger splits once it is properly hot.

Ground that will not work

The method has real limits and it is worth knowing them before you dig.

• Waterlogged or high water table ground. The hole fills with water. Common across much of lowland Britain in winter.
• Pure sand or very loose soil. The walls collapse, particularly the intake tunnel. Some clay content is what makes this work.
• Thin soil over rock. You cannot get the depth.
• Heavily rooted ground. Roots block the tunnel, and burning tree roots is a genuine hazard: fire can travel along a root system underground and emerge somewhere else hours later.
• Peat. This is the important one.

Putting it out and leaving no trace

Doing this properly is what distinguishes a Dakota hole from just a hole with a fire in it.

1. Let it burn down to embers rather than smothering a live fire.
2. Drown it. Water on the embers, stirred through with a stick, and repeat until you can hold your hand in the ash. This takes more water than you expect and is not optional: a Dakota hole holds heat very well, which is exactly the problem when you want it out.
3. Feel it with the back of your hand. If there is any warmth at all, it is not out.
4. Fill the intake tunnel first, then the chamber, packing the soil back in and treading it down.
5. Replace the turf and press it firmly. Water it.
6. Scatter leaf litter over the seam.

Done well, the site is genuinely hard to spot within a day or two, and completely invisible within a season.