[Terrapreta] pulverizing charcoal

[David Yarrow]

thursday last week, i spread my first batch of biochar on one of my garden 
beds.  the char was produced by my friend dan kittredge in the process of 
burning underbrush he is clearing from land on the concord, MA farm he 
manages.  he brought me two medium size plastic sacks full -- perhaps 25-30 
gallons.

i decided to reduce the sticks and branches to dust and chunks, and i needed 
it done quick.  my insights say large chunks of char are slowly, gradually 
invaded and inhabited by water and microbes (weeks, maybe months), while 
small half inch or less particles are quickly saturated with water and 
overrun by fully diverse microbial communities.  so the smaller the particle 
size, the faster the char will be fully performing its multi-function soil 
magic.  and in my spring vegetable gardens, i want the char to get into 
action almost immediately.

my method was primitive and personsal.  i closed each sack and pounded it 
with the broad side of a square-headed 3# hammer, then screened it through 
half inch hardware cloth.  the larger pieces that wouldn't pass the screen 
went back in the sack for more abuse with the hammer.  this was repeated 
three more times until all that was left were a few chunks of hard uncharred 
wood.

i don't like smashing char, since the physical force crushes and collapses 
some of the micropore structures.  such a brute physical process requires a 
lot of energy -- i worked up a sweat swinging the heavy hammer and shaking 
the screen.  but the whole operation only took 30-40 minutes.

the char was spread on the middle half of my kitchen garden, covered with 
compost, traprock dust, greensand, rock phosphate and sea minerals, then 
various brassicas, lettuces, endive, and herb seedlings were transplanted 
in.  my first biochar soil test.

later this week, i will repeat this with a bag of comercial hardwood 
barbeque charcoal.  i'll get another bag of commercial charcoal and try 
soaking batches in various solutions, including fresh water, sea mineral 
water, EM water, compost tea, and urine to compare how quickly the char 
absorbs water and becomes easy to crush.

for a green & peaceful planet,
David Yarrow
44 Gilligan Rd, E Greenbush, NY 12061
www.championtrees.org
www.OnondagaLakePeaceFestival.org
www.farmandfood.org
www.SeaAgri.com