New uses for gypsum in agriculture will be highlighted at the Midwest Soil Improvement Symposium: Research and Practical Insights into Using Gypsum on Aug. 23.
The event will be held at the University of Wisconsin Arlington Agricultural Research Station.
The symposium will explore the impact of gypsum application on crop productivity, including for corn, soybeans, alfalfa and specialty crops, and its impact on soil and water quality. Research findings and application recommendations will be presented, as well as background on gypsum production and safety. In addition, there will be two panel discussions featuring growers experienced in using gypsum on their farms.
The benefits of using gypsum in agriculture were recognized more than 200 years ago. Because it was expensive to mine and transport, gypsum was limited to use in certain high-value specialty crops such as peanuts and potatoes. New, low-cost sources of gypsum are available now thanks to industrial processes that create gypsum as a by-product.
Many coal-fired utilities use advanced scrubbing systems to remove sulfur dioxide (SO2) from their emissions. These scrubbers produce high-quality and very pure FGD gypsum or calcium sulfate dihydrate (CaSO4 * 2H2O). According to utility industry surveys, annual production of FGD gypsum is currently approximately 18 million tons and could double in the next ten years. In addition to FGD gypsum, co-product gypsum is derived from fermenting corn for food products.
Applying by-product gypsum is a good method of recycling, says Dr. Richard P. Wolkowski, a University of Wisconsin-Madison senior scientist and extension soil scientist and co-host for the symposium. "What would normally be landfilled is now being used to supply plant fertility needs. Gypsum is an excellent source of calcium and sulfur for crops.
Furthermore, there is evidence to show gypsum has a positive effect on soil properties, and our trials have shown that applications of gypsum may reduce the concentration of soluble phosphorus in the soil which is important from an environmental standpoint, says Wolkowski.
When gypsum is applied at rates of one to two tons/acre per year, we are seeing that tight, compacted clay soils will loosen over time and become easier to work, says Ron Chamberlain, director of gypsum programs for Beneficial Reuse Management, marketer of GYPSOIL brand gypsum. Increased water infiltration, less soil erosion and evidence of an improved biological environment with more earthworms deep into the soil profile, are also evident.
Research trials highlighted
Dr. Wolkowski and Dr. Meghan Buckley of the University of Wisconsin-Stevens Point will discuss several gypsum research studies now underway in Wisconsin. One study at the Arlington facility is comparing the response of alfalfa to gypsum at rates of 1, 2, and 4 tons per acre. Alfalfa yield, tissue nutrient concentration, soil physical properties, and soil test are being measured.
A second study is being conducted at the Arlington site to examine the crop yield and leaf nutrient content response of corn fertilized with several rates of N to FGD gypsum. A series of on-farm studies located in heavy soils in the Green Bay and Superior, WI, area are examining the response of corn to FGD gypsum applied at several rates.
The symposium will highlight several other gypsum studies currently underway. Other researchers who will be presenting include:
Dr. Warren Dick, professor, environmental and natural resources, Ohio State University, Wooster, OH, will discuss gypsum benefits to crop productivity;
Dr. Dexter B. Watts, research soil scientist, USDA-Agricultural Research Service, Auburn, AL, will discuss soil and water quality and research on using gypsum on buffer strips to reduce soluble phosphorus in surface water runoff;
Dr. Darrell Norton, soil scientist, National Soil Erosion Research Lab, USDA-Agricultural Research Service, West Lafayette, IN, (invited) who discuss the impact of gypsum on the environment;
Dr. Rufus Chaney, research agronomist, Environmental Management and Byproduct Utilization Laboratory, USDA-Agricultural Research Service, Beltsville, MD, will deliver a risk assessment for beneficial use of FGD gypsum in agriculture via webinar;
Dr. Harry H. Schomberg, ecologist, J. Phil Campbell, Sr, National Resource Conservation Center, USDA-Agricultural Research Service, Watkinsville, GA, will describe evaluations of FGD Gypsums; Dr. Birl Lowery, professor, Soil Science, University of Wisconsin, will lead tours of gypsum research plots at the Arlington site.
The Arlington Research Station is located at N695 Hopkins Road, Arlington, Wis. The cost of the symposium is $15 in advance and $20 at the door. For more information or to register online visit http://www.gypsoil.com/symposium.