PULLMAN, Wash. – Alternatives to traditional tillage practices in agriculture are the topic of an article by Washington State University Regents Professor John Reganold and Pullman-based USDA Agricultural Research Service scientist David Huggins published in the July issue of Scientific American. The article is Reganold’s third for Scientific American.
Titled “No-Till: The Quiet Revolution,” the article describes an alternative to traditional tillage practices. For thousands of years, farmers have prepared soil for planting by plowing. Turning the soil, though, leaves it vulnerable to wind and water erosion.
“By the late 1970s in the Palouse,” Huggins and Reganold write, “soil erosion had removed 100 percent of the topsoil from 10 percent of the cropland, along with another 25 to 75 percent of the topsoil from another 60 percent of that land.”
Conventional tillage practices also can cause runoff of soil sediment, fertilizers and pesticides into rivers, lakes and oceans.
No-till agriculture, in contrast, does not disturb soil nearly as much. Instead of turning over broad swaths of soil, no-till equipment cuts a narrow groove into which seeds are planted. Residues of previous crops are left on the ground, creating a moisture-holding, erosion-preventing mulch that reduces toxic runoff, creates habit for wildlife and soil fauna such as worms and increases the organic content of soils.
While no-till agriculture is practiced on about 41 percent of U.S. farms, only a tiny fraction of the world’s 525 million farms practice no-till. Barriers to adoption of no-till include the fact that farmers in developing countries need crop residue for fuel and animal feed. Also, startup costs for no-till agriculture are high, with equipment costing as much as $100,000.
Still, Reganold and Huggins see no-till techniques as part of a larger suite of practices that will contribute to sustainable agriculture. Other tools being developed include pest-management practices that lessen pesticide resistance, various organic practices, as well as growing a diversity of crops in rotation which, the authors write, will help “break up the weed, pest and disease cycles that arise when one species is continuously grown.”