Soil Samples (72) were collected from the Delta, Hill, and Northeast Blackland areas of Mississippi. Chemical analyses for manganese, magnesium, and calcium were made using the Mississippi Soil Test Solution (MSTS) and several other extracting solutions chosen for comparison. For the determination of available soil manganese, the MSTS proved to be as effective as either the Double Acid (0.025NHCl in 0.05NH2SO4) or 0.1NH3PO4. The acid extractants removed more manganese than 1NNH4OAc (pH 7.0) and therefore included forms that are not exchangeable. The methods studied for magnesium determinations were equilibrium extraction with 1NNH4OAc, MSTS, Double Acid, 0.25NCaCl2, and leaching with 1NNH4OAc. All methods were highly correlated and therefore would be equally effective in determining available soil magnesium. Since MSTS and equilibrium extraction with 1NNH4OAc removed similar amounts of magnesium from the soil, the same calibration can be used. Calcium determinations were made using equilibrium extraction with 1NNH4OAc, MSTS, and Double Acid, and by leaching with 1NNH4OAc. All methods proved effective in measuring available soil calcium on acid soils.