People are funny. Take, for instance, a fellow gardener who, a couple of months ago, shared with me her excitement about a biochar workshop she had attended. “I can’t wait to get back into my garden and start making and using biochar,” she said. Biochar, one of gardening’s new wunderkind, is what remains after you burn wood with insufficient air — charcoal, that is. Stirred into the soil, its myriad nooks and crannies provide an expansive adsorptive surface for microbes and chemicals, natural and otherwise. Biochar, being black, darkens the soil, and dark soil is generally associated with fertility, although that’s not always the case. Because biochar is mostly elementary carbon, it resists microbial decomposition, so it’s carbon is less apt to end up in the atmosphere as carbon dioxide.