The idea of using biochar to enhance urban soils came on strong last week at the Sustainable Sites Symposium in Chicago. The quality of a landscape depends largely on the quality of its soils. Root invigoration research indicates a tree given a more productive enviroment doesn’t need as many roots to thrive. This can have huge implications for urban forestry. Biochar can help support a larger and more vigorous urban canopy. However biochar effects are complex, affected by source, pyrolysis process, and site dynamics.  There is little research to support urban use of biochar, but the value of potential soil health improvements assures eventual study. Symposium attendee Christine Esposito reports that the City of Chicago is receptive to making sites available to study biochar in urban soils. I am thinking Lopa Brunjes could use this story to good effect in her February biochar presentation to TED.

Range managers promote the health of living soil systems as essential to sustained business viability.

That forage productivity is a function of soil health is not news. What is news is our evolving appreciation of soil health in terms of a living system. Restored soil is a highly valuable asset in most any setting, and the more intense the land use, the more to be contributed by good soil. Ecological restoration and urban redevelopment have much to gain from the grazing schools of soil husbandry.

There are lots of bits to this puzzle, but when it comes to sustaining life in soil, the energy bit is not to be forgotten. Mulch and compost delivers food energy. Soy bean meal, used to improve soil structure in public turf and playing fields, works similarly.

Cover crops and woody vegetation work to sustain a healthy symbiotic rhizospheric soil community on root exudate rich in food energy. This is a different microbial community than is working on the sloughed root mass, on soy bean meal, mulch and compost – a healthy soil has both a rhizosheric community and a bulk (jargon for outside the rhizospheric soil enveloping the root) soil community thriving in concert.

Gary Jones has posted about this article also, and alludes to a food energy feast available in the context of pulse grazing.

Pulse grazing jolts the system in a good way, and there is a lesson to be learned here that is applicable to urban soils where drastic disturbance often causes the system to loses species diversity. When it comes time to revive soil life, the rate of restoration is slowed by a combination of extremely low population, an excess of predators which restrict re-population, and absent the species diversity needed to share in the restoration dynamic. Pulsed management is an important tool for overcoming this inertia.

Building a diverse palette of soil microbial species in a drastically disturbed site, this is a worthwhile challenge, this is the acme of success. Soil health, wealth, and wisdom.

Recently I had the opportunity to watch a clip of Storm Cunningham’s stirring presentation to the TEDxMidAtlantic 2010 conference. He speaks to the economic dynamo that builds when communities revitalize their resources. Storm Cunningham terms it the restoration economy, and the scope is awesome; natural and cultural resources, urban and rural. I see renewal in terms of soils, and the role I can play, and I get excited. At its core, this is what my work is about.