Loss of Playa Wetlands Caused by Reclassification and Remapping of Hydric Soils on the Southern High Plains

Historically, playas in the Southern High Plains (SHP) were identified by the presence of hydric soils. The United States Department of Agriculture (USDA) has begun a reclassification and remapping of upland and depressional soils for the playa region of Texas. For eight counties in Texas, we compared the occurrence of playas, as indicated by soils designated as hydric in original soil surveys, to designations in remapped soil surveys. We estimate a 65% decrease in playa numbers and 50% decrease in area as defined by the presence of hydric soil. Anthropogenic impacts, resulting in an altered hydrology and masking of hydric soil are proposed as primary factors responsible for reduction in playa numbers. Other potential factors include current USDA methodology and correction of historical survey errors. Playas on the SHP being considered for inclusion under USDA conservation programs must be individually and independently assessed on-site for wetland criteria, rather than reliance on revised USDA-NRCS Soil Survey maps. During on-site evaluations, effects of anthropogenic alterations on the playa soil to develop and maintain hydric characteristics must be considered. Until completion of the remapping effort, confusion will ensue with the use of the online USDA-NRCS Soil Survey maps during interpretation by those unfamiliar with the status of soil survey reports for the Texas SHP