Experimental Homestead

Soil Banking With Biochar: proposition for a migrating latrine system aimed at permanent soil improvement

“The idea is to have a sort of trench system that would serve both as a latrine, and as a means of permanently improving the soil.”



This proposal is built around the concept of using charcoal to permanently improve soils.  If you’re not familiar with that idea, a little reading on biochar might be helpful. 2 3 

(EDIT: Ok, I just posted this yesterday, but the original title sucked, so I had to take action.  The more I’ve thought about this idea today, the more I’m inclined to think that viewing it as just a latrine is somewhat limiting.  A system of soil improvement like this could serve to accommodate all sorts of rubbish and organic refuse.  I always thought that if I built a nice outhouse someday, that I’d make a sign for it that said Bank of Fertility (make a deposit:).  I like that concept.  I’m going to go with the term Soil Banking for the concept of a migrating soil improvement  system using an open trench.  While making daily deposits of doodie makes eminent sense for such a system, there are so many more things that could be tossed in the mix.  All people who live in the country that don’t have access to landfills, have rubbish heaps or pits of some kind.  What I’m proposing is that we use that open pit, and the material added, to a high level of advantage toward the end of permanent soil improvement.  At this point, I can only see a big open pit, placed in the right area, to be an outstanding opportunity.  The idea of permanent soil improvement, made possible by the addition of charcoal, is really compelling.  Dead animals and parts, rotten wood, old natural fiber clothing, shells, bones, ashes, seedy weeds that are best not put in to the compost, anything else that plants or soil life can feed on that the chickens can’t eat, or that we don’t want to put in the compost for whatever reason, and of course poo and charcoal, all added as they occur.  And of course adding whatever other amendments, like lime, rock powder or trace minerals might make sense too, depending on circumstances.  Over many years, this system could add up to an ever expanding bank of super soils that will probably continue to be superior for decades, if not for centuries.  So there it is, Soil Banking.  “What should I do with this dead maggoty possum?”  “put it in the soil bank with a few scoops of charcoal and some dirt”  “yeah, okay, I was going there to make a deposit anyway!” “righteous dude, high five!”  Now back to regularly scheduled programing.)

I’ve been knocking this idea around in my head for a while.  Actually, maybe it’s been knocking me around it just want’s me to think that I’m knocking it around.  It started when I was thinking about ways to use the pit after pit burning charcoal in a long trench.  The obvious use was to bury the biochar in it instead of digging another hole for that.  After all, it’s one thing to make all that char, but then you have to dig it into the soil, which is a butt load of work.  In this climate, outside of irrigated garden beds, I think getting the char pretty deep is probably a good idea.  After june, soil moisture is scant near the surface.  If the char was buried lets say only 12 to 18 inches deep, that puts it in the zone where roots are mostly on idle for the summer.  No moisture= no root activity to speak of.  Charcoal is a great retainer of moisture, but it’s not that great.  I’m talking about unirrigated areas for orchards and perrenials, or maybe for dry farming crops.  If the char was more like 3 feet or 1 meter deep, it would be of much more benefit to plants in the summer season. Continue reading

July 29, 2014 Posted by | Garden Stuff | , , , , | 17 Comments