FGD-gypsum is a soluble source of Ca and S, thus improving plant nutrition. FGD products, applied at rates sufficient to supply 30 lbs/acre of S, increased corn grain yields over a three year period from 113 bu/acre to 120 bu/acre. The relative yields of corn grain were greater at low N than at high N fertilizer rates suggesting improved N use efficiency. This will provide more profit to farmers and help reduce N pollution of the environment. In addition to improving nutrient levels in soil, FGD-gypsum applied at much higher rates (1,500-3,000 lbs/acre) also improves soil physical properties. This resulted in increased yield of corn grain under a no-tillage system, presumably by promoting soil aggregation and by increasing water surface infiltration rates and water movement into and through the soil profile. Chemical properties improved by application of FGD-gypsum include the mitigation of subsoil acidity and Al toxicity. Preliminary results suggest that the gypsum/no-tillage system had economic advantages compared to the no-gypsum/conventional tillage system for soybean production.

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