Air dry moisture content (2A1)

This method is required to adjust soil chemical results based on air-dry samples to an oven-dry (105^oC)
basis. When the air-dry moisture content (M%) is known, the correction from air-dry
to oven-dry is as follows:

            Oven-dry result  =   [Air-dry result  x  (100+ M%)]/100

(9.00E+01)

Exchangeable Bases - Ammonium Acetate (15D3)

Exchangeable bases - 1M ammonium acetate at pH 7.0.

This rapid method for exchangeable cations in non-saline acidic through to slightly alkaline soils has no pre-treatment for soluble salts. It should yield similar data to those of method 15A1, except it can overestimate exchangeable Ca in soils containing calcium carbonate.