Study: Sustainable Farming Proven to Increase Yield at Zero Cost

New study finds that longer rotations and increased crops can significantly reduce chemical use in conventional agriculture. (Photo by NRCS_Oregon via Flickr)

Study: Sustainable Farming Proven to Increase Yield at Zero Cost

Bittman: "Most Important Ag Study" goes largely unnoticed

In potentially "the most important agricultural study this year," researchers find that sustainable farming methods can help conventional agriculture "shed much of its chemical use," according to New York Times writer and food author Mark Bittman.

The Marsden Farm study, conducted by a team of government and university researchers, is a large-scale, long-term experiment that took place over the course of nine years (2003-2011) on land owned by Iowa State University. On 22 acres, researchers planted three parallel plots: one replicating the conventional Midwestern farming cycle alternating corn and soybeans each year with a routine mix of chemicals; in the second, planting a three-year cycle that included oats and a red clover cover crop; the third was planted on a 4-year rotation that added alfalfa (a key livestock feed). The two longer rotations also integrated the use of manure, or livestock fertilizer.

Researchers compared the systems on productivity, profitability, and environmental health and the findings--published earlier this month in the journal PLOS One--according to Bittman, "are stunning:"

The longer rotations produced better yields of both corn and soy, reduced the need for nitrogen fertilizer and herbicides by up to 88 percent, reduced the amounts of toxins in groundwater 200-fold and didn't reduce profits by a single cent.

"These were simple changes patterned after those used by North American farmers for generations," said Adam Davis, an author of the study who works for the U.S.D.A. "What we found was that if you don't hold the natural forces back they are going to work for you."

Bittman, summarizing the report's abstract, writes: "So: combine crop rotation, the re-integration of animals into crop production and intelligent farming, and you can use chemicals to fine-tune rather than drive the system, with no loss in performance and in fact the gain of animal products."

The study observed that these more sustainable methods are more labor intensive: increased crop rotation, mulching, the reintegration of animals, more exposure and knowledge of the fields, more observations, etc. Davis adds, "you substitute producer knowledge for blindly using inputs."

Karen Stillerman, writing for the Union of Concerned Scientists, notes that "some people will no doubt see this as a strike against crop diversification. But with energy costs on the rise and unemployment stuck just under 8 percent, that's starting to seem like seriously fuzzy logic."

Despite the astounding good news, very little has been said about it. As Bittman observes, the study has been "largely ignored by the media, two of the leading science journals and even one of the study's sponsors, the often hapless Department of Agriculture."

The agency declined to comment when I asked about it. One can guess that perhaps no one at the higher levels even knows about it, or that they're afraid to tell Monsanto about agency-supported research that demonstrates a decreased need for chemicals.

This study not only questions those assumptions, it demonstrates that the chemicals contributing to "environmental externalities" can be drastically reduced at no sacrifice, except to that of the bottom line of chemical companies. That direction is in the interest of most of us -- or at least those whose well-being doesn't rely on that bottom line.

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