I recently attended two sessions of the Carbon Farming Course organized by Appleseed Permaculture with the support of many progressive and forward thinking agricultural organizations. The course was held at the Pfeiffer Center for Biodynamic Farming at Chestnut Ridge, New York, and offered several workshops in regenerative agriculture featuring speakers at the top of their profession and recognized nationally, and in some cases, internationally.
I selected two out of several workshops that appealed to me. Each was three days long and covered the topics in great detail so that participants came away with, not only a theoretical introduction to the topics, but hands-on, practical applications.
The first workshop was on the subject of Perennial Agriculture and was taught jointly by Dr. Wes Jackson of The Land Institute in Salina, Kansas, and Dave Jacke, author of "Edible Forest Gardens". Both these teachers are tops in their field and gave generously of their knowledge to the participants.
Perennial agriculture is the complete opposite of what agriculture is today. Except for fruit production, most agriculture worldwide is focused on annual crops. Grains are at the top of the list for crops grown around the world. These include (in order of importance): wheat, rice, maize (corn), soybeans, barley, sorghum, cottonseed, dry beans, millet and rapeseed/mustard. These crops cover approximately 80% of global agricultural land.
Along with these very important staple foods, other crops, such as most of our vegetables, are annuals and must be replanted and then harvested each year. Dr. Jackson, plant geneticist, noticed the high costs and inputs that go into an annual cropping system each year. Yearly applications of ertilizers, pesticides, equipment costs etc. must be factored into the costs of farming annuals. The shallow-rooted annual plants and then the bare soil of the "off season" leads to severe soil erosion, depletion of soil fertility and also water contamination.
One need only look on the internet for a satellite photograph of the dead zone in the Gulf of Mexico to see the negative effects of annual agriculture from the Mississippi River basin and the North American prairies (the "breadbasket" of the nation) to understand how much real wealth has been lost through careless and thoughtless agricultural practices since the opening of the prairies. The phenomenon of loss of soil through erosion and contamination of water by excessive use of fertilizers and the use of pesticides, is not unique to North America but has affected every continent and every ecosystem on the planet.
Perennial agriculture seeks to return to a type of agriculture that corresponds better to ecology. Before the settlers started farming the prairies, rich polycultures of plants grew on extraordinary soils with deep, fertile topsoils, the likes of which had never been seen by Europeans before. The equivalent of the prairie soils had been discovered and developed in the Russian steppes too.
Dr. Jackson and the research team at The Land Institute are breeding perennial wheat and other grains to replace the annuals now in production around the world. The perennials would create large root systems that would hold the remaining soil and protect it from erosion, contribute to the creation of deepening and improving the fertility of the soil and reduce costs of production because of the reduced need for fertilizer and other inputs.
Dave Jacke's approach to perennial agriculture takes the form of mimicking another type of natural ecosystem - the woodland. Woodlands and forests generally contain many layers of vegetation. The overstory of trees, depending on the species and density, often has a shrub layer and a ground cover layer of herbaceous perennials and annuals. The soil remains covered. Root depths vary species to species and the variety of plants grow in their niches complementing the growth of their neighbors in various ways.
Deep rooted plants draw moisture and nutrients up to shallower depths where roots of other plants can access these necessary ingredients for growth. Beneficial relationships between the plants and the soil microbial populations develop undisturbed by frequent tilling. Waste products from plants, falling leaves and branches, and exudates from roots, for example, contribute to soil fertility by cycling the nutrients into the soil where soil organisms utilize them. Eventually, those nutrients are convered back into forms useful again to the plants. These materials are not leaching into groundwater as agricultural fertilizers often do.
By understanding these cycles of nature, Dave Jacke teaches how to design a polycultural system using trees, shrubs, vines, perennial and annual herbaceous plants. These edible forest gardens, when carefully designed, will become self-sustaining, needing very little effort and manipulation by the human tender.
An edible forest garden may consist of one tree, two or three shrubs and a dozen or so herbaceous plants. Or, it may be a forest garden that covers many acres. Whatever the size, careful selection and placement of the plants and the access paths permit the growth of food and possibly fiber and building material too, in sustainable systems that require little, if any, outside inputs of fertilizers and pesticides.
References that I recommend for more reading on designing edible forest gardens are:
"Creating a Forest Garden: Working With Nature To Grow Edible Crops" by Martin Crawford, www.greenbooks.co.uk ISBN 978 1 900322 621.
"Edible Forest Gardens" Volume 1 and Volume 2, by Dave Jacke with Eric Toensmeier, www.chelseagreen.com ISBN 1-931498-80-6.
"How To Make A Forest Garden", Patrick Whitefield, www.chelseagreen.com
ISBN 13:978-1-85623-008-7
The second of the three-day workshops I attended was The Living Soil with Dr. Elaine Ingham as presenter. Check back to this site soon for a description of this valuable workshop.
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