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Keeping cows and forage on the farm may mean less room for corn, but it solves two big problems that plague conventional agriculture: the soil degradation caused by growing all the grain in one place and the manure pollution caused by feeding all the cows in another. As Darryl Amey, an organic farmer in Saskatchewan, puts it: "When you put 2,000 pigs in one place, you have a pollution problem. Put 2,000 pigs out on 10 mixed farms, and you have fertilizer."
In what must be the longest-running organic trial in the world—150 years—the Rothamsted Experimental Station (also known as the Institute of Arable Crops Research) in England reports that its organic manured plots have delivered wheat yields of 1.58 tons per acre, compared to synthetically fertilized plots that have yielded 1.55 tons per acre. That may not seem like much, but those manured plots contain six times the organic matter found in the chemically treated plots. Again, the organic system is based on the assumption that at any given time, some of the acreage is planted with a fodder crop that will go to feed cows. The synthetically fed plots are based on a profoundly different assumption: that their survival depends on a fertilizer factory somewhere that is consuming vast amounts of fossil fuels and emitting greenhouse gases.
In 1989 the National Research Council wrote up case studies of eight organic farms that ranged from a 400-acre grain/livestock farm in Ohio to 1,400 acres of grapes in California and Arizona. The organic farms' average yields were generally equal to or better than the average yields of the conventional high-intensity farms surrounding them—and, once again, they could be sustained year after year without costly synthetic inputs.
And a 1987 study that compared adjoining organic and chemically treated wheat fields in Washington State found that the organic fields had 8 more inches of topsoil than their chemical neighbors and only one-third the erosion loss.
The anecdotal evidence perhaps speaks most loudly of all. Talk to organic farmers and most will relate a similar experience: When they first gave up chemical inputs, they experienced disappointing yields. But after several years of building the soil's natural fertility, the farmers found that their harvests came close to, or exceeded, chemical yields.
One of those organic farmers is Fred Kirschenmann of North Dakota. He saw his yields plummet when in 1977 he abruptly eliminated all fertilizers and pesticides from his 3,100-acre farm. But today his yields match the highest of his conventional neighbors except during droughts, when his humus-rich soil provides even higher yields than neighboring farms.
"If we have an ideal growing season, conventional farmers tend to outyield us," Kirschenmann says. "But if there is any stress on the crop, drought or too much rain, we tend to outyield them."
New research is showing that organic farming does not have to suffer lower yields, even in the early years. Consultants to German farms converting to organic practices have learned that by starting off with a nitrogen-rich leguminous cover crop instead of a grain crop, an initial drop in yield can be avoided.
A 1993 scientific comparison of farms in New Zealand found that biodynamic organic farms had better soil structure than that of neighboring farms that used conventional techniques. Their soil also had better aeration and drainage, was more easily tilled, and had higher organic matter and nitrogen content. And both types of farms were equally profitable.
Not all the evidence is so clear-cut. Some studies show that chemical yields outperform organic. What is amazing is that organic systems have performed as well as they have despite receiving almost no support from traditional agricultural research institutions, which overwhelmingly work within the chemical-farming paradigm.
What we can conclude after reviewing the evidence about organic yields is this: The expectation that they will always trail chemical yields is without merit. After a few years of practicing organic methods, and with very little scientific research to guide them, many farmers have come close to duplicating the high yields achieved by the world's most intensive chemical farmers, who have been supported by decades of government and academic research. At the same time, the organic methods have repaired much of the environmental damage caused by the chemicals.
