I took a trip to the shops to buy sake for discharging various debts of gratitude, and on my way I was excited to see a chimney poking out of a pile of rice husks, disgorging clouds of white and brown smoke. A strange cause for excitement you might think, but this is a procedure for making a very effective soil amendment, and I've been interested in this for some time, without being aware that it's being practised in my neighbourhood. Here's a PDF explaining the method and the benefits, and the same information in HTML format.
I hopped out of my car, made my way through the stubble fields to where the pile was smoking and greeted the old lady who attended it, hoping not to make her jump. Not only did she not jump, she graciously answered all my questions and even offered me a bag of processed husks for my garden. Care is required to water the heap at suitable intervals to prevent the husks from burning up to grey dust. The lady had been tending her fire constantly for two days.
So with the young master pushing the wheelbarrow, we went to claim our bagful. In the storehouse of the farm we could see the clean and modern de-husking machine that had produced all this chaff, in marked contrast to the not clean and not modern charcoal making 'facility' outside in the field. It occurs to me that the de-husking machine could really do with a charcoal burning attachment that can capture and cool the smoke to use as an organic pesticide and fertilizer.
The question is now what to do with my precious rice charcoal. A tiny bag of charcoal a fraction of this size costs nearly 300 yen, so this is a sizeable treasure. Having already planted my winter veg, I'm wondering how best to apply this.
I went across the fields in the dark after the charcoal burning work was finished and had a look at the can and chimney arrangement - simplicity itself. I already have a can, and a chimney is easy enough to come by. And rice husks are available for the asking. Terra Preta in our lifetime?