Abilene Soil Survey Office Provides Soil Samples for Chloride Study and Benchmark Soils

The Abilene Soil Survey Office was tasked to sample ten (10) soil pedons* and submit to the lab for full characterization and analysis. The team of soil scientists in the Abilene Office consists of William Shoup, Project Leader; Riley Dayberry, Soil Scientist; and Jo Parsley, Soil Scientist. The staff analyzed the best possible matches for the soil series locations to be sampled by using remote sensing, GIS data and products, and studying official soil series descriptions (and their locations). Soil Scientists spent numerous days in the field collecting the data, examining past transects and pedon descriptions from the immediate area, and reviewing the soil classifications. Cooperation from landowners to allow access to their lands, was essential in the collection of soils for analysis.

Nine very deep soils were selected, along with one moderately deep soil. A primary focus was placed on pedons that matched the descriptors for a soil chloride study, provided by a cooperator, Texas A&M University. One pedon (Lueders) was classified as a benchmark soil, but didn’t have any existing data, so the data collected will provide information for both the Soil Data Mart as well as the Benchmark Soils project.

The Chloride Study that is being conducted by Texas A&M University is thought to have relevant significance in the Rolling Red Prairies of Central and West Texas, of which the soils have the proper characteristics and precipitation levels. Essentially, the study is trying to understand the movement of chloride, as a function of land use, specifically rangeland with and without brush control. The hypothesis is that the more brush, the more difficult to move chlorides below the rooting zone as compared to sites without brush (grassland). The source of the chlorides is from atmospheric dust and rainfall. Cropping history of each site was recorded, for irrigation and fertilization additions to the system. Results will be published at a later date.

The Benchmark Soils Project is ongoing, and the Abilene Soil Survey office has responsibility for twelve benchmark soils. These benchmark soils have lab data history that range from zero (Lueders), to fourteen records (Leeray). The project plan consists of sampling at a minimum one of each series within the major land resource area (MLRA), in order to produce proper lab data and interpretations that are significant to the region. A priority has been placed on series with the least amount of data. The benchmark soils found in this area are Abilene, Hardeman, Hollister, Leeray, Lueders, Miles, Palopinto, Sagerton, Throck, Tillman, Truce, and Vernon.

Lab data for the individual pedons were sent to two separate National Soil Survey Cooperators, Texas A&M University (soil chloride study pedons), and Texas Tech University (benchmark status pedon). The lab data will provide insight not only for a graduate-funded research project, but also will populate a never before sampled benchmark series, and provide more useful data for all users of soil survey information. Overall, it helps to develop tacit knowledge of soils located within the major land resource area (MLRA), making soil scientists more knowledgeable of the soils.

Additional information on these projects may be available by contacting the Abilene Soil Survey Office.

Users can obtain the most up-to-date soils information on use and management, soil properties, soil characteristics, and soil potentials and limitations through Web Soil Survey at http://websoilsurvey.nrcs.usda.gov.

*A pedon is described as the smallest volume that can be called "a soil." A pedon is three dimensional and large enough to permit study of all horizons. Its area ranges from about 10 to 100 square feet (1 square meter to 10 square meters), depending on the variability of the soil.