From: THE AVANT GARDENER Vol. 41, No.2 December 2008
It could be the most important development in agriculture and horticulture of this century. Adding charcoal - charred organic material, not ashes, to soil remarkable improves both its productive capacity and its ability to trap the greenhouse gasses which are the cause of global warming.
"Biochar" is so promising that an International Biochar Initiative was established in England in September www.biochar-international.org and a Senate amendment to the 2008 Farm Bill promotes extensive research on biochar's "value for soil enhancement and carbon sequestration."
The worlds's richest soils are the biochar or terra preta del indio soils of Amazonia in Brazil. The early Indian dewllers of that region burned trees and tilled in the charred remains. Charcoal lasts for thousands of years, and it slows the breakdown of organic matter and also provides sites on which nutruents can be adsorbed.
The Indians added fish and animal manures and bones; recent tests with typical weathered tropical soils show that adding both charcoal and fertilizer can increase crop yields almost tenfold. And when charcoal was added at 20 pounds per 100 square feet to fertile soils in England, soybean biomass doubled, wheat biomass tripled.
Decrease of greenhouse gasses could be tremendous. Research in Colorado has shown that adding biochar to soils cut nitrous oxide emissions 80% and almost totally eliminated methane emissions. A British scientist says that adding biochar to all the world's arable soils could theoretecally enable them to hold all the carbon dioxide in the atmosphere today.
The Amazon Indians, incidentally, were believed to have moved frequently because their slash-and-burn operations depleted the soils. On the contrary, they moved because weeds grew so luxuriantly in the biochar soils that they overwhelmed crops.
So save some charred wood from the fireplace this winter and add it with organic fertilizer to some test plants next year. Someday we may be making biocharring' as regular a practice as composting. As Jean English reports in MAINE ORGANIC FARMER AND GARDENER (Box 170, Unity, ME 04988), Sustainable Harvest International has demonstrated that "biochar can be made simply by piling any organic material, setting it on fire and covering it with soil to exclude air."
THE AVANT GARDENER is published monthly ($24 per year, $30 outside USA
Horticultural Data Processors, Box 489, New York, NY 10028
Thomas Powell, Editor and Publisher
(This is a great little, simple, no frills gardening newsletter, that brings the absolute very newest gardening information. There is no advertising. There aren't any illustrations or photos, just articles packed with new, wide ranging gardening imformation about growing things. It is especially at the forefront of introducing new cultivars, anything and everything from rice to roses.)
I cant wait to try some charcoal in the gardens next spring.