I've been meaning to try the Dakota fire hole for quite sometime but just never got to it, but today was a good day for it so off I went to the woods. One explanation I've heard for this method of fire was that the Plains Indians used it to keep the fire low so as to avoid prairie fires due to the wind blowing the embers away, I don't know whether this is true or not but it does make sense me.
It's a rather a simple design as that the fire burns in a hole to keep the flames low and the air is supplied to the fuel by a draft vent to the bottom of the hole where the fire is burning. It can be dug with a digging stick and scooped out by hand in more primitive conditions but a trowel or small shovel makes the job easier. I took along a Cold Steel shovel and I dug my initial hole about a foot deep or so and probably about a foot in diameter.
The draft vent was started a little over a foot away upwind of the fire hole, I drove a make shift digging stick in at about 45 degrees from there to the bottom of the fire hole.
Working the digging stick in the draft vent I got it to where it was about 2 inches in diameter to the bottom where it enters the fire hole.
For what it's worth standing back about twenty feet or so it's not very noticeable that there is even a fire there, although I could see a slight amount of smoke.
I gave boiling some water a shot in my French canteen cup by placing some green branches over the hole as a grate, I'm not sure how long it took as I didn't time it but it seemed to boil in a short amount of time.
I'm happy with this design of fire and how well it went, one could experiment with the size and depth of the hole and draft vent to suit various purposes. One thing I should mention, I have read that this fire shouldn't be used where the soil has a high organic content because of the chance of fire burning underground or catching roots on fire.