Biochar: Now it begins....

retort 1
retort 1

Somewhat over a year since we contracted with New England Biochar for a retort, we finally have it.   Because of the demand for them and necessary production time, we expected about a one-year wait for it, after we got in line.  Because of continual upgrades and improvements to the units, it took a little longer, but we received a retort that is much better than what we signed up for.  As soon as the weather breaks, Bob Wells and Peter Hirst, the owners of New England Biochar, will spend a week with us to commission the retort and train us in its use.  It sounds like a real combination of art and science to properly operate it.  Too hot, and the biochar carbon structure collapses, making it useless as biochar.  Too cool, and not all the volatiles are cooked out, also making it useless as biochar.  So, soon we'll start the process.

We are obviously novices in the biochar movement, but continually learning more.  This movement is so new, most people we talk to have never even heard of biochar.  If this includes you, let me share a little of what I've learned about it.

My son Sean and I had been sharing articles back and forth on biochar for a few years, when my brother Rich told me about a book he just read, 1491, by Charles Mann.  He said one of the appendices described a special soil along the Amazon River.  I interrupted him with the words "terra preta".  "How did you know that?" he said.  I told him how I'd been reading articles about it for awhile.  Interestingly, Bob Wells also learned of biochar just like Rich, in 1491.  He describes that in a book he co-authored, along with Peter Hirst and other notable biochar pioneers, The Biochar Revolution.  

Terra preta, or "dark earth", exists in areas along the Amazon River.  The soil is some of the richest in the world, teeming with beneficial microbes, and as you might guess, has a high percentage of charcoal.  Most of the soil along the Amazon is just like potter's clay - very infertile.  For hundreds of years nobody really knew much about it, but anthropologists and archaeologists have been studying it for a while now and are figuring out where it came from.   Turns out that native Americans put charcoal from fires in the soil.  It allowed them to grow crops where they otherwise probably wouldn't have.

Scientists have recently figured out why it makes the soil so fertile.  Biochar is not a fertilizer.  It actually is rather inert.  When biomass cooks into char, rather than burning into ash, the carbon forms a crystalline structure that is hollow.  This structure turns out to be an ideal home for beneficial microbes- bacteria, fungi, mycorrhizae, etc.  It has been likened to a coral reef in the ocean.  It also increases the surface area that plant roots have available for absorbing nutrients.  In fact, one gram of biochar has an internal surface area, that if laid out flat, would cover 100 square meters.  I'm not very good with metrics, so I looked it up.  One gram is 1/28th of an ounce!  Covering an area larger than 30' x 30'!  It also makes a great moisture buffer, like a sponge.  Bottom line is, that coupled with a good fertilizer like COF (see previous post, The Progression of Health), soil with biochar grows much larger, healthier plants and produce.

As beneficial as it is for farmers and gardeners, it turns out that a potentially even more important aspect is to reverse climate change by sequestering carbon in soil, and thus lowering atmospheric carbon (in the form of carbon dioxide.)  Listen to Albert Bates, author of The Biochar Solution, describe this.

As we begin this great adventure, we'll be relaying what we learn and experience.  Stay tuned.

Steve