The reality >>

Thanks to author Michael Pollan’s eye-opening Omnivore’s Dilemma and a host of other books about local eating, food miles are on everyone’s minds these days. And for good reason: On average, food travels 1,300 to 2,000 miles from farm to plate. But choosing local alone can’t solve our fossil-fuel and CO2 woes, say researchers. Only 11 percent of a food’s carbon footprint is tied to transport. The remainder is almost entirely associated with growing, processing, and packaging the food, which in the case of conventional agriculture includes copious amounts of fossil fuel-derived fertilizers, herbicides, and pesticides.

Organic farming takes those nonrenewable petroleum products out of the equation (instead it relies on cover crops and organic fertilizers to boost productivity, and nonpetroleum-based pest and weed management tools). But newly published research from the Rodale Institute points to an even bigger potential environmental benefit of organic farming: carbon sequestration.

Looking at nearly three decades of research, Jeff Moyer, farm director of the Rodale Institute and Chairman of the National Organic Standards Board (NOSB), and other scientists such as David Pimentel at Cornell have found that healthy, microbe-rich soil bolstered by organic farming methods has the ability to remove CO2 (the most prevalent greenhouse gas) from the air—and lots of it. “By increasing and replenishing biodiversity in the soil we can sequester carbon at a greater rate than we originally thought possible,” says Moyer. An acre of organic cropland can take approximately 7,000 pounds of carbon dioxide out of the atmosphere each year. Multiply that by the 434 million acres of U.S. cropland and it becomes the equivalent of eliminating emissions from 217 million cars (nearly 88 percent of cars in the U.S. today).

How does dirt become a carbon-sequestering tool? By using cover crops, organic compost, and chemical-free pest and weed control practices, organic farming actively builds biodiversity in the soil. In fact, if you took the microscopic fungi living in a teaspoon of soil from organically managed farmland and placed them end-to-end, the resulting chain would stretch hundreds of yards, says Moyer, many times more than conventionally farmed soil, which has been bombarded with synthetic pesticides and highly concentrated nitrogen. The fungi and other living organisms abundant in organic soils naturally pull carbon from the air and store it in the soil where it is retained for decades. Scientists have found that, at worst, some Midwestern soils have gone from 20 percent carbon to between 1 and 2 percent carbon in the last 60 years alone.

The bottom line, carbon aside? “Just because a food is local doesn’t mean it wasn’t sprayed with chemicals,” says Scowcroft. “Those chemicals are local to somewhere,” he says. “There are thousands and thousands of chemicals not being used on organic farms.” (See Pesticides and Your Health for an update on some of the worst offenders.) “Chemical companies are very much in favor of the local movement because it takes the focus off of how the food is grown,” says Moyer. “We’d like people to support local farmers,” he says. “At the same time, we want those farms to be organic. Let’s have a voice in how those farms are being managed.”