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EWG Report Reveals Soil Erosion Higher Than USDA Data Indicates

posted on April 14, 2011

The thought of using a mold-board plow to prepare a field for planting has become as much of an oddity as using the horses to pull it. Farmers know soil is what makes it all happen and without that black gold there isn't much of a chance to put something in the bin. In order to keep as much of the good earth in place, millions of government dollars have been spent on the construction of buffer strips and farmers have changed best management practices to incorporate either no-till or reduced tillage planting methods.

But a recent study from The Environmental Working Group -- utilizing data from soil scientists at Iowa State University -- revealed all may not be as good as once thought when it comes to keeping Mother Earth in place.

EWG Report Reveals Soil Erosion Higher Than USDA Data Indicates After years of planting an increasing number of buffer-strips and a surge in the use of no-till planting protocols, there is evidence it may have not been enough to sufficiently slow soil erosion in Midwestern fields. A study released this week by the Environmental Working Group, or EWG, revealed the soil in the nation's top corn producing state may be slipping away faster than once believed.

Scientists at Iowa State University analyzed 18,000 samples gathered between 2002 and 2010 on Iowa farm land and discovered more soil was going into the Mississippi River Watershed than official USDA estimates.

In 2010, USDA released data showing soil loss in Iowa fields of 5.2 tons per acre per year – slightly higher than the 5 tons per acre government officials consider sustainable without reducing productivity. But, analysis of Iowa State University data by the Environmental Working Group, heavy rains and the incentive of higher prices encouraging fence-row-to-fence-row planting practices, have contributed to soil erosion rates of up to 12 times that amount. At 64 tons per acre, both ISU scientists and EWG researchers are concerned about the ability of farmers to maintain sustainability and increase production. They also are concerned about the impact of increased erosion contributes to expansion of the so-called "dead zone" in the Gulf of Mexico - an area along the southern U.S. coastline where oxygen depleted water incapable of supporting marine life.

The environmental watchdog has been pushing USDA to tighten enforcement of a law requiring farmers to protect highly erodible land from soil loss or risk losing federal subsidies and loans.

USDA officials point out they already provide funding for erosion control projects like buffer strips and encourage farmers to follow best management practices to keep soil in the field and out of America's waterways.

Tags: agriculture erosion news oil USDA