Effects of FGD Gypsum on Crop Yield and Soil Properties of an on-Farm Study.

Increasing the productivity of agricultural soils is important to sustainably supply food, feed, fuel, and fiber for a growing human population. Recent claims that gypsum, used as a soil amendment, can improve the productivity of some soils have sparked interest among producers, stakeholders, and researchers to evaluate the potential benefits. Thus, an on-farm study was conducted in the Tennessee Valley Region of North AL to evaluate the effectiveness of using flue gas desulfurization (FGD) gypsum to improve soil and crop production. FGD gypsum was applied at a rate of 0, 1.1, 2.2, and 4.4 kg ha-1to an agricultural field under row-crop production. The field was managed according to the farmer’s current cultural practices. Gypsum applications increased soil Ca and S concentrations, decreased water-extractable P concentrations, and had minimal effect on soil pH. There was no observable effect on crop yield. This study was evaluated on a highly productive soil. Future work will be conducted on less productive soils that have subsoil acidity problems.