The guys running one farm down in Boone County Iowa get this. In Big, Smart and Green, from Wired, there is a great article giving an example of who 'traditional farming techniques' can bring enlightenment,
- The Marsden Farm experiment, which is described in a study published Oct. 10 in Public Library of Science One, started in 2003, when Davis was a graduate student under agronomist Matt Liebman of Iowa State University. Liebman’s specialty is integrated pest management, or strategies that use nature to accomplish what’s typically done with pesticides, herbicides and synthetic fertilizer.
- [T]he researchers rotated over three years between corn, soy and oats, with red clover planted in winter. The clover, which absorbs atmospheric nitrogen, was planted between crop rows and plowed under as soil-replenishing “green manure” in spring. On another plot, instead of red clover the researchers planted a fourth-year crop of alfalfa, which can be used to feed livestock. The animals’ manure came back as fertilizer.
- Having different crops with different life cycles made it harder for
weeds to grow. What might flourish among corn and soy, for example, was
disrupted by oats. When red clover and alfalfa were mowed, weeds were
chewed up before they flowered. As for insect problems, low pesticide
use, along with habitat provided by cover crops, allowed pest-eating
bugs and birds to flourish.
After eight years, Liebman and Davis used eight times less herbicide in the three- and four-year rotations than in the conventional plot, they report in the new study. Ecotoxicity in surrounding water was two orders of magnitude lower. Thanks to clover and alfalfa, the experimental plots also used 86 percent less synthetic fertilizer.
Most important of all, the experimental plots were as productive as the conventional. They produced just as much total crop biomass. When the researchers calculated the value of their environmentally friendly harvest, it was every bit as profitable.
“We exceeded those goals — not by pumping chemicals in, but by maximizing ecosystem services,” Davis said. “We’re not throwing away those tools. They’re very important. But you use a strong cropping system as the foundation for your agriculture. Then, when you need it, you tweak it a little bit with the inputs.”
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