Conservation planners associated with the Gulf Coastal Plains and Ozarks (GCPO) and Gulf Coast Prairie (GCP) Landscape Conservation Cooperative (LCCs) require contemporary and standardized vegetation maps from coastal Texas to Alabama. Marsh salinity zone maps are used by conservation planners to model habitat availability for priority taxa (e.g., waterfowl and alligator) and for understanding impacts to priority habitats. The USGS National Wetlands Research Center has been funded by the U.S. Geological Survey South Central Climate Science Center to map marsh vegetation salinity classes (i.e., fresh, intermediate, brackish, and saline) from Corpus Christi, Texas, to Mobile Bay, Alabama. Researchers from Texas A&M University-Kingsville and University of Louisiana-Lafayette collected ground reference data via helicopter surveys. Imagery from Landsat 5 TM and Satellite Pour l'Observation de la Terre (SPOT) 4 and 5 were combined with elevation data and other ancillary data (e.g., National Wetlands Inventory [NWI] maps, and the Coastal Change Assessment Program [C-CAP]). These data were classified into marsh salinity classes using classification and regression tree (CART) analyses and combined with existing classifications of marsh vegetation salinity in Louisiana to develop a contemporary and continuous coastal vegetation layer for much of the Gulf of Mexico coast.