Wednesday, July 4, 2007

carbonizing corn in the field

I have already commented earlier in how I thought that the Indians in the Amazon likely created windrows that they then lightly buried and set afire. Today I figured out the rest of it.

When a corn stalk is pulled out of the ground, the root ball resembles an eight inch wide disk. This allows the building of a wall of inward pointing corn stalks in which the earthen root ball forms a brick on the outer surface. The stalks will stack and pack very well. Of course, you build a matching wall on the other side of the first stack so that you get a two sided bank protected by the root balls. With any luck the tops of the stalks will compact well and a small space of a several inches can be left between the two halves for fire ignition. The compaction could allow the formation of an arched top to the bank that continues the root ball surface unto the top of the bank.

The ends of the bank can then be sealed off with with either more stalks or more likely a little earth. The same holds true for any gaps in the roof. Building one of these things would even be fun for the community, since pulling the corn is very easy work.

It is then a simple matter to wait for the right time to set this stack afire and you have a natural carbonizing oven. Two days later, you have a nice pile of reduced carbonized corn waste mixed with dirt that can be forked unto seed hills for the next corn crop. It really is that easy and only requires a little bit of additional effort in the stacking.

What I am very conscious of is that is not a lot of work compared to what many other crops require. A family could even do this today on any simple one acre patch, anywhere in the world.

2 comments:

arclein said...

This idea has been much advanced and more fully understood since I wrote this. Slathering on wet clay helps to seal off the resultant earthen kiln.

Maise pollen is associated with the archeological record, although any dry soft plant tissue available in qantity will work as well.

The compelling argument for corn stalks with root ball is that the quantity is sufficient and after harvest, the moisture in the stalks retreats leaving a dry stalk suitable for charing.

If they failed to take advantage of maize, we certainly can.

arclein said...

A further consideration that has bedeviled biochar productiion is that few can get wood out of their thinking. It is only slowly that people are coming to understand that terra preta is and must be made from soft plant material.

Biochar will have a surviving fraction of pure carbon that will never be chemically rebound unless it is burned.

Wood produces charcoal in large inconvenient chunks and it fails to crush easily. Avoid it if you are making biochar.