I have re-read your correspondence with much interest.
I would actually like to turn your "Ravina Biochar Project" one of the 'official' "Urban Test Plots" of Biochar Ontario, if possible.
In addition, I would also like to work closely with you (and other researchers such as Dr. Brad Bass [CC'd] and perhaps the University of Toronto and/or Ryerson and others [like Humber College @ their Arboretum? & York U. etc.]) so that we can eventually extend this project beyond just "veggie plots".
Essentially, I would like to create / set up an "urban/suburban Biochar plot testing network" as they have been doing in Seattle for the past year or more. [see: Seattle Biochar Working Group: http://seachar.org/, where they are running a "citizen science project" at SSCC -- the South Seattle Community College : http://seachar.org/archives/473]
We should also be looking at a variety of other "backyard" and urban settings to do these types of experiments -- including using it for Urban (and sub-urban | peri-urban) Reforestation (CC Sandy Smith), Urban Streetscaping, Green roofs/walls, Permaculture gardens, Landscaping and a variety of other "garden plots" in cities [and the suburbs].
(Note: Part of the purpose of CUS-T is to act as a "Agroecological Support Hub" for this "citizen science" Network.)
First, I would like to know more about the "high quality commercial hardwood charcoal" that you are using.
--> What is the brand name?
I have successfully used "Commercial" hardwood charcoal as well - specifically some well screened [using a 6mm Soil Sieve], granular char from "Charbon de bois franc Basques" i.e. "Basques Hardwood Charcoal" that is made in Québec.
This Char that is made by Basques is from hardwood logs which are "unfit for sawmills". Most of his product is destined for grilling in restaurants, but the "fines" were (until the Biochar Industry came along) of very little value. [They did sell a certain volume of granular and powder charcoal by bulk truck or "super sacks" into various markets (horticultural or industrial) ~ at about 10 cents a pound, but it was in quite limited quantities.]
** Note: The Basques Biochar had been "characterized" (using some early tests for "porosity"* that were developed by Hugh McLaughlin of Alterna Biocarbon, in labs that were set up in Massachusetts, USA).
*Importantly, porosity is a property that can only be established during manufacture of the Biochar, which is the reason that the source of Biochar that you are using needs to be well known [characterized] and of consistent quality.
I am, however, also interested in undertaking some trials using "mixed feedstock" Biochar -- produced using a variety of 'mixed feedstocks' that will [hopefully] result in a 'broad range' of characteristics for the Biochar. I am hoping that, like compost tea, that this type of "multi-Biochar" product could be able to 'jumpstart' a broad diversity of micro-organisms or some similar [existing or introduced] microbial communities in soils ... i.e. the variety of chars in the mixture might act like 'inoculants' for various strains of microbes, thus helping to increase soil [microbial] biodiversity in a variety of ecotypes.
This might of course, require a somewhat more complicated 'characterization' and testing process to ensure that none of the Biochars are 'toxic' [to the plants being grown], however most of what we learn about the various Biochar and amendment combinations|applications will probably come as a result of this small-scale "experimentation" by the members of the (citizen science) network who I hope will be trying|experimenting with a variety of different chars and techniques.
(I actually think that it might actually be this well-organized 'Citizen Science' Testing Network that ultimately may end up being of greatest value to the manufacturers of the various Biochars, and may help us to bring various 'Corporate' members / supporters into the Biochar Ontario [not-for-profit] network -- which may itself become the local Co-op that distributes the various "commercial" Biochars [to their own members] on behalf of the companies making them.)
All of this is essentially part of "Biocharculture" (sort of an adjunct to "Agriculture" and "Permaculture" techniques), where the "raw" Biochars are "treated" by [for instance] soaking it in urine [as you are doing], and/or seeding it with microbes or key bacteria [including appropriate strains of nitrogen-fixing bacteria and B-vitamin-synthesizing microbes], or simply blending the Biochar with compost, mycorrhyzae, digestate and other 'cultures' to provide a source of "organic food" for the infant microbial communities that may already exist in the soils (or that are introduced from other healthy soils -- often Forest soils).
Note: These 'treatments' (of the Biochar) are usually necessary to rapidly 'upgrade' the Biochar into a fast-acting soil additive, and should help to minimize the time required to get a strong positive effect in the soil.
(In this sense, somewhat like Permacuture, "Biocharculture" is based on a key set of scientific principles, and it's practical application in various settings is almost as much of an "art" as it is a "science".)
To give credit to the term "Biocharculture", I must acknowledge the Chief Executive Officer of the Geoecology Energy Organisation (GEO) in Hyderābād, India, Dr. N. Sai Bhaskar Reddy (Nakka), who has been successfully utilizing "Biochar compost" for the past few years in his country. He is part of the "vanguard" of a new Biochar-based agricultural paradigm shift, away from "Green Revolution" technologies and toward "holistic" growing [gardening / farming] techniques (and which also includes many|most of the Organic and Permaculture techniques).
P.S. Thank you very much for letting me know about the University of Toronto's two-day "Cities Centre" research workshop, "Finding Connections: Towards a Holistic View of City Systems", to be held on October 10-11 2012!
I do hope to be able to attend this event as well.
Lloyd Helferty, Engineering Technologist Principal, Biochar Consulting (Canada) www.biochar-consulting.ca 48 Suncrest Blvd, Thornhill, ON, Canada 905-707-8754 CELL: 647-886-8754 Skype: lloyd.helferty Steering Committee coordinator Canadian Biochar Initiative (CBI) President, Co-founder & CBI Liaison, Biochar-Ontario Partner of Toronto Urban Ag Summit! www.urbanagsummit.org See also: http://www.facebook.com/UrbanAgSummit Manager, Biochar Offsets Group: http://www.linkedin.com/groups?home=&gid=2446475 Advisory Committee Member, IBI http://www.linkedin.com/groups?gid=1404717 http://www.facebook.com/group.php?gid=42237506675 http://groups.google.com/group/biochar-ontario http://www.meetup.com/biocharontario/ http://www.biocharontario.ca www.biochar.ca "The history of every nation is eventually written in the way it cares for its soil." - Franklin D. Roosevelt