I’ve just read about "biochar" in the latest issue of Avant Gardener: "It could be the most important development in agriculture and horticulture of this century. Adding charcoal – charred organic material, not ashes – to soil remarkably improves both its productive capacity and its ability to trap greenhouse gases which are the cause of global warming." It sounds too good to be true, but a web search took me to Cornell University and from them to Nature magazine. Apparently this is real.
Does anyone know how to apply this to the home garden? (i.e. What would be a good source of the appropriate charcoal if I wanted to experiment?)