Farms, schools, soil, and dirt

As the Comparative Farming & Sustainable Food Systems course has progressed, I have, predictably, gotten farther and farther behind in my reading. In part, this is due to the continuing snowstorm of papers, theses, articles, poems, essays, and miscellaneous book recommendations we keep getting from our professor, Craig Gerlach, and his teaching assistant, Bob Mikol (not to mention the occasional suggested piece from various students in the class). There is just no way to keep up. I'm keeping a couple of binders and printing out the various publications I get from them, and I keep finding new and interesting titles to purchase at Gulliver's. These include:

The Taste for Civilization: The Connection Between Food, Politics, and Civil Society, by Janet A. Flammang, and The End of Food, by Paul Roberts

Likewise, I've not been able to keep up with blogging on the class. Johanna Harron came in to talk to us about the Farm-to-School program set up by the state of Alaska (she's the program's only employee so far). The program covers school nutrition, local food systems, and education around food. Nancy Tarnai did an interview with her about her thesis project and about the program.

Last week, Mike Emers of Rosie Creek Farm taught the class, concentrating on soil, dirt, and some farming how-to. So far it has been very interesting. He told us about the phrase "organic farming," apparently coined by one Lord Northborne in 1940 in his book Look to the Land. Mike also told us about Rudolf Steiner, the father of biodynamic agriculture, or the view that a farm as a whole should or can be seen as an organism.

One thing Mike said sticks in my mind: "Farming is a manipulative process." It's all about managing sunlight, water, and soil, he said (and plants and animals, of course). Maintaining economic and ecologic sustainability is a matter of minimizing off-farm inputs to sustain the farm in perpetuity. That requires a lot of work, a lot of manipulation of the systems on the farm. He offered a list of useful books, bringing in well-worn and frankly battered copies of each of them:

• The New Organic Grower, by Eliot Coleman
• Organic Vegetable Production
  
• Building Soils for Better Crops, by Fred Magdoff and Harold van Es
  
• The Soul of Soil, by Grace Gershuny and Joe Smillie
• Larding the Lean Earth: Soil and Society in Nineteenth-Century America, by Steven Stoll
  
• Sustainable Vegetable Production from Start-Up to Market (dated but still great, Mike said)

He also recommended an article by William S. Cooter, "Ecological Dimensions of Medieval Agrarian Systems," published in Agricultural History.

Mike mostly concentrated on soil. He described four basic elements of soil that are important to the farmer: structure, soil organic matter (the key to how most organic farmers manage the soil), biology, and nutrients (including water). There was quite a bit of interesting info in this discussion, which explained a few things that I'd never quite understood, although I've been working with soil scientists here at SNRAS for a good decade and had seen some of the terms. Plants, Mike said, decompose into very small, complex particles that have negative charges, which attract cations of the nutrients plants need and hold onto water. The cation exchange capacity of soil is its ability to exchange positive ions of nutrients between organic matter and plant root hairs. Good tilth exists when there is good soil structure and high soil organic matter. Humus is compost broken down further into soil organic matter, very tiny pieces that are useable by plants. Most farms in the country, Mike explained, have very low SOM, about one half of one percent, because of erosion, soil compaction from heavy machinery, chemical contamination due to salt buildup from chemical fertilizers, and poor tilling practices that destroy soil structure.

The problem of poor tillage was broached in the movie The Plow That Broke the Plains. The culprits in poor tillage are (aside from a farmer's failure to understand the value of good soil structure) excessive use of the moldboard plow, the disc harrow, and the rototiller. Good soil has clods (little ones) that hold moisture and nutrients. Too much tilling breaks up these clods, and accelerates microbial action which then releases carbon and breaks down the soil organic matter. Rototilling, in fact, can turn your soil into powdery dust. Overtillage did just that (combined with drought years) during the Dust Bowl.

Mike described machinery that has been invented that doesn't destroy the soil structure, or at least not as much: the chisel plow, the articulating spader, and a couple of other gizmos. Mike liked a company owned by a pair of inventor brothers, I think this company in Pennsylvania.

We then went on to talk about green manure, fallowing, and cover crops, no-till methods which seem to require either herbicides or crushing implements to keep the off-season greeneries from becoming weeds later on. No-tillage farming results in more perennial weeds and it cools the soil---not an advantage in the north.

More later!

Cross-posted at SNRAS Science & News.

Previous posts in this series:

Seven industrial agriculture myths

Farming systems and Food, Inc.

Financial finagling in food and sustainability
Food systems, policy, and foodsheds
Food systems and shizen
Sustainable food systems class