When thinking about technology, I like to play with the idea of what is the absolute minimum you need to get the job done.  This may be because I’m not very handy at building things, but yet have survivalist tendencies. So while I’m pretty sure I’ll never actually have any need for these skills, it’s fun to think about how I’d get by in a DIY world.

So I was delighted when I ran across this minimalist grain storage technique on the BBC documentary series, A History of Celtic Britain (2011), hosted by Neil Oliver of the Delicious Scottish Accent. (I am watching it on YouTube. Fingers crossed the BBC will not take it down before I finish it!)  I love this technique because while it is simple, it is far from stupid.

The technique is described by the Dave Freeman of the Butser Ancient Farm in Hampshire, where they’ve been experimenting with grain storage iron-age style (c. 400 BCE.).  Turns out all you need to do is dig a pit in the soil. The pits they dug are circular, and look to be 2 or 3 feet in diameter, and maybe 3 or 4 feet deep.

So you may ask, how can you pour grain into a hole in the ground and expect it to keep? The secret is a clay cap on the top. In the screen grab below you can see the cap and some feet for scale:

If you go to YouTube,  you can watch this sequence starting around 52:36, but what Freemen says is that when the grain goes in the pit and is sealed with a clay cap, the clay blocks out moisture, air and light. Moisture is still available at the sides and bottom of the pit, of course, especially as they are in green Hampshire.

The grain touching the sides of the pit sucks the moisture out of the soil at the edges, and uses it to attempt to germinate. The germination process sucks up oxygen and releases carbon dioxide, effectively clearing the chamber of oxygen. At that point, as Neil puts it, “Time stops.” Nothing can grow, nothing changes. The grain cache keeps for at least a year, perhaps two years, and provided a very handy safety backup for hard working iron age farmers. And some very basic appropriate tech for modern armchair survivalists to ponder.