Many Farmers and Gardeners Turn Away From Tilling
27 September 2010
A farmer tilling a field near Hastings, Minnesota, in April
This is the VOA Special English Agriculture Report.
Farmers and gardeners have turned the soil for centuries. But many now believe in no-till or reduced tillage, a method also called conservation tillage. The Conservation Technology Information Center says forty percent of American cropland used this method at last report.
Tilling can remove weeds and the waste from last season's crops and help break down old plant material into fertilizer. But it can also increase the risk of soil erosion by rain or wind.
Tilling also releases carbon dioxide from the soil into the atmosphere. No-till keeps carbon in the soil and avoids the release of heat-trapping gases from motorized equipment. It also keeps water in the soil and protects helpful organisms like earthworms. And it saves money on labor, machinery and fuel.
A recent study reported on almost twenty years of different tillage methods in the American states of Colorado, Kansas and Nebraska.
The researchers say tillage makes soil less resistant to being broken apart by raindrops than plowed soil. They say no-till stores more soil carbon, which helps the soil particles stick together. They found that the first two and a half centimeters of topsoil are up to seven times stronger against rain than plowed soil.
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