SEDL / STP / STP1162-EB / STP23869S

Collection and Preparation of Soil Samples for the Federal Soil Survey Laboratory Program

Brown, LE
Staff leader, Soil Characterization Staff, and Section leader, Physical Analysis Section, USDA, Soil Conservation Service, National Soil Survey Center, Lincoln, NE

Reinsch, TG
Staff leader, Soil Characterization Staff, and Section leader, Physical Analysis Section, USDA, Soil Conservation Service, National Soil Survey Center, Lincoln, NE

Pages: 9    Published: Jan 1993

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Abstract

Field observations are employed in the soil survey process to develop concepts f representative soils within the mapped area. At least one site is selected to represent each soil component of each soil map unit. Time and budget constraints usually dictate that only a few sites may be sampled. Each soil horizon at a sampling site is described and sampled. The samples include bulk soil material and specimens of natural fabric. The method used to process the sample in the laboratory depends upon properties of the soil and upon the requested analyses. Rock fragments >20 mm in diameter are determined in the field, and rock fragments <20 mm are measured in the laboratory. The fine earth material is homogenized and saved for chemical, physical, and mineralogical analyses. The laboratory data are used to classify and characterize the soil.