This project uses data from a 22-acre cropping systems experiment at the ISU Marsden Farm to investigate differences in crop yields, soil properties, pathogen dynamics, agrichemical and energy use, production costs and net returns and selected ecological impacts. The plots compare three rotations: conventional 2-year rotation of corn-soybean and two more diverse systems, a 3-year corn-soybean-oat + red clover rotation and a 4-yr corn-soybean-oat + alfalfa-alfalfa rotation. This project will provide new knowledge about weed seed bank dynamics and how herbicide regimes affect fossil energy inputs, greenhouse gas emissions, ozone formation and factors in Life Cycle Assessment (LCA). Leopold Center funds leverage other USDA grants related to this research.
Matt Liebman is the H.A. Wallace Endowed Chair for Sustainable Agriculture and a professor in the ISU Agronomy Department. He specializes in agricultural ecology, specifically ways to use ecological processes to reduce dependency on agrichemicals and fossil fuels. His research looks at diversified cropping systems, organic matter amendments to soils, weed ecology and management and the use of native perennials for soil and water conservation and biofuel production. In 2013, he was honored with the Spencer Award for Sustainable Agriculture and Practical Farmers of Iowa’s Sustainable Agriculture Achievement Award. He has degrees from Harvard and the University of California.
Ann Johanns, Iowa State University Extension and Outreach
Jason Hill, University of Minnesota-St. Paul