"Waste" Gypsum Could Help Boost Crop Yields

By Don Comis
May 27, 1999

Instead of going to a landfill, gypsum from electric power plant smokestacks can be sold to farmers to raise corn and soybean yields while protecting soil from erosion. The tactic is still in the research stage, but it’s being applied on hundreds of thousands of acres in Indiana and Illinois, according to soil scientist Darrell Norton at the Agricultural Research Service, USDA's chief scientific agency.

Norton is scheduled to present his research findings today at the 10th International Soil Conservation Organization Conference, held May 23-28 in West Lafayette, Ind. The conference theme is “Sustaining the Global Farm: Local Action for Land Stewardship.”

Norton has shown that gypsum “waste” from power plants helps soil hold more water, by preventing soil from crusting so more rainwater enters the soil instead of running off the field. In the past, gypsum from quarries has been used to loosen soil, to treat soils high in sodium or toxic aluminum, and to fertilize soils deficient in calcium or sulfur, according to Norton.

Norton leads ARS' National Soil Erosion Research Laboratory in West Lafayette. The laboratory is co-hosting the conference along with Purdue University and USDA’s Natural Resources Conservation Service.

Ralph Woodward, a corn and soybean farmer who works with Norton, farms in an area where most soils are low in calcium and sulfur. The discovery of soil and water benefits from gypsum from power plants is icing on the cake. Woodward believes these benefits will increase over time and show significant yield increases. He believes so strongly in the potential economic and environmental benefits of power plant gypsum that he has a Purdue graduate student doing gypsum research on his farm, in cooperation with Norton and the Indianapolis Power and Light Company.

Ken Curtis, of Prairie City, Illinois, another farmer who works with Norton, also runs a business applying power plant gypsum on other farmers’ fields. Trucks that used to return from the grain elevator empty now return full of gypsum.

Since the Clean Air Act of 1990 and subsequent revisions, scrubbers added to power plant smokestacks are generating increasing amounts of gypsum.

Scientific contact: Darrell Norton, ARS National Soil Erosion Research Laboratory, West Lafayette, Ind., phone (765) 494-8673, fax (765) 494-5948, nortond@ecn.purdue.edu.