This vegetation classification and mapping effort encompasses 167,148 ha(413,031 acres ) within the San Luis Valley, west of the Sangre de Cristo Mountains in south central Colorado. The mapping boundary is made up of several management units from a variety of government and private agencies (and a small amount of private property). These include the National Park Service (Great Sand Dunes National Park and Preserve – 60,354 ha, 149,137 acres), U.S. Fish & Wildlife Service (Baca National Wildlife Refuge – 37,483 ha, 92,623 acres), U.S. Forest Service, Bureau of Land Management (Blanca Wetlands), and the Nature Conservancy (Medano-Zapata Ranch – 13,243 ha, 32,725 acres). The mapped area includes portions of Saguache and Alamosa Counties. The actual mapping boundary reflects the U.S. Forest Service fire management plan area and is thus an effort by the NPS-USGS mapping program to encompass not only lands within the NPS but also those that are in proximity and that have some type of ecological or management cohesiveness. The final map product was produced in two parts. The USFWS Baca National Wildlife Refuge was produced by USFWS personnel and the remaining portion by NatureServe, Colorado Natural Heritage Program, USGS, Bureau of Reclamation, and National Park Service staff. Constant communication between these parallel efforts allowed for consistency in both accuracy and classification. Both FWS and NPS information is presented in this ServCat Record.