Tuesday, November 6, 2007 - 1:45 PM
196-2

Gypsum Soils from a Soil Survey Perspective.

Susan Casby-Horton1, David Hammer2, Thomas Reinsch1, and Nelson Rolong1. (1) USDA-NRCS, 101 South Main Street, Temple, TX 76501, (2) USDA-NRCS, NSSC, 100 Centennial Mall N, Fedrl Bldg Rm 152, Lincoln, NE 68508-3866

Assessment of gypsum soils has gained in importance with progressive soil mapping in the western United States.  Physical and chemical properties of these soils, including low water and nutrient retention capacity, tendency to corrode iron and concrete, and dissolution leading to structural shifting and collapse, suggest that gypsum soils are marginal for production agriculture and costly for urban expansion.  Important steps in this assessment are determination of the appropriate laboratory techniques to produce these properties and qualities and assignment of accurate soil properties and qualities to generate valid interpretations.  Equally important is an understanding of soil genesis and soil-landscape processes, particularly in relation to hydrology, surface stability, and landscape evolution.