Flue gas desulfurization (FGD) gypsum is a by-product of the process that removes sulfur from the gas emissions stream of coal fired electric power plants. FGD gypsum is currently being soil in Wisconsin to producers as a soil amendment and sulfur source. Most of the current work on FGD gypsum for row crop production in the Midwest is taking place in Ohio on soils that are very different from those in Wisconsin (Chen et al., 2008). The goal of this study was to better understand the effect of gypsum on corn production and soils under no tillage and conventional tillage cropping systems with six different rates of nitrogen fertilizer in Wisconsin.