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Calcium and magnesium are extracted from the soil by shaking a 1-gram scoop of air-dried soil with 10 milliliters of 1 N (pH7) ammonium acetate (NH4OAc) for 5 minutes. The filtered extract is analyzed via inductively coupled plasma optical emission spectrometer (ICP-OES). The results are reported in parts per million (ppm) calcium (Ca) and magnesium (Mg) in the soil.