“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.”
“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.”
http://www.organicconsumers.org/articles/article_26749.cfm
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