Effects of Liming Materials on Soil pH
Forage productivity and quality are related to soil pH and nutrient availability. Soil pH is the measure of acidity or alkalinity. In Mississippi, over 60% of the forage production acres are acidic with a pH of less than 5.8 in which remedial actions will be needed. Most nutrients are optimally available to plants within a pH range of 5.5 to 7.0, as this range is generally very compatible with healthy plant root growth. Soil pH of 6.5 is usually considered optimum for nutrient availability. Liming is commonly used to improve the productivity of acidic soils in pasture and hay systems by increasing the availability of nutrients and microbial activity that result in increased decomposition of soil organic matter decomposition to release mineral nitrogen, phosphorous, and carbon. Liming also increases root growth and reduces the elemental accumulation of aluminum (Al), manganese (Mn), and iron (Fe) which are toxic to plants in excess. At low soil pH nutrients such as calcium, phosphorus, and magnesium are less available to the plant.