Effects of Multiple-Year Gypsum Applications On Alfalfa Yield and Root Growth On Non-Sodic Ohio Soils.

Gypsum is a relatively common mineral that is widely available in agricultural areas and has a number of specialized agronomic uses, principally as a Ca source on legumes and as a soil conditioner on sodic soils. Large amounts of gypsum are produced as a by-product of electricity generation from coal-fired power plants. With the increased availability of synthetic gypsum, applications to non-sodic soils in Ohio and the rest of the Midwest are increasing. Several studies have concentrated on analysis of the effects of gypsum on surface structure, crusting, infiltration, and erosion. However, few studies have analyzed hydrologic effects of gypsum below the surface, especially in the root zone. The purpose of this study was to determine and compare the effect of gypsum amendment on alfalfa yield production and root growth on non-sodic soils with different drainage class (Celina-well drained and Brookston- poorly drained), and different gypsum application regimes (control, short term application (3 years) and long term application (12 years) in no-till fields. The study was conducted using 18 undisturbed soil columns (30.5 cm diameter and 80 cm depth) sampled from fields near Eaton, Ohio.