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Lab Services: Soil testing

Lab Services: Soil testing

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Test Method Title

Standard Test Methods for Moisture, Ash, and Organic Matter of Peat and Other Organic Soils.

Reference Number

ASTM D2974



Test Property

Moisture content, ash content, organic matter content

Description of Test

Test Method A—Moisture is determined by drying a peat or organic soil sample at 105°C. The moisture content is expressed either as a percent of the oven dry mass or of the as-received mass. Test Method B—This is an alternative moisture method which removes the total moisture in two steps: ( 1) evaporation of moisture in air at room temperature (air-drying), and (2) the subsequent oven drying of the air-dried sample at 105°C. This method provides a more stable sample, the air-dried sample, when tests for nitrogen, pH, cation exchange, and the like are to be made. Test Methods C and D—Ash content of a peat or organic soil sample is determined by igniting the oven-dried sample from the moisture content determination in a muffle furnace at 440°C (Method C) or 750°C (Method D). The substance remaining after ignition is the ash. The ash content is expressed as a percentage of the mass of the oven-dried sample. Organic matter is determined by subtracting percent ash content from one hundred.

Preferred Test Sample Size

Number of Test Specimens


Test Specimen Size

At least 50 grams


Moisture content, Ash content, organic content

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