from the otherwise-known-as-how-we-used-to-do-it dept.
Erica Goode writes in the NYT that no-till soil-conservation farming, a movement that promotes leaving fields untilled, “green manures” and other soil-enhancing methods, is gaining converts as propnents say the technology mimics the biology of virgin land, to revive degenerated earth, minimize erosion, encourage plant growth and increase farmers’ profits, “It’s a massive paradigm shift,” says Ray Archuleta, an agronomist at the Natural Resources Conservation Service, part of the federal Agriculture Department, which endorses the soil-conservation approach. Neatly tilled fields have long been a hallmark of American agriculture and its farmers, by and large traditionalists who often distrust practices that diverge from time-honored methods. Tilling also helps mix in fertilizers and manure and loosens the top layer of the soil. But repeated plowing exacts a price. It degrades soil, killing off its biology, including beneficial fungi and earthworms, and leaving it, as Archuleta puts it, “naked, thirsty, hungry and running a fever.” Soil health proponents say that by leaving fields unplowed and using cover crops, which act as sinks for nitrogen and other nutrients, growers can increase the amount of organic matter in their soil, making it better able to absorb and retain water.
One recent study led by the Environmental Defense Fund suggested that the widespread use of cover crops and other soil-health practices could reduce nitrogen pollution in the Upper Mississippi and Ohio River basins by 30 percent, helping to shrink the giant “dead zone” of oxygen-depleted water in the Gulf of Mexico. But the movement also has critics, who argue that no-tillage and other methods are impractical and too expensive for many growers. A farmer who wants to shift to no-tillage, for example, must purchase new equipment, like a no-till seeder. Even farmers who enthusiastically adopt no-till and other soil-conservation methods rarely do so for environmental reasons; their motivation is more pragmatic. “My goal is to improve my soil so I can grow a better crop so I can make more money,” says Terry McAlister, who farms 6,000 acres of drought-stricken cropland in North Texas. “If I can help the environment in the process, fine, but that’s not my goal.”