Prairie remnant next to railroad track in Southwest Louisiana.

Coastal prairie in Louisiana once covered an estimated 2.5 million acres. As a result of rice and sugarcane production, oil exploration, and residential and industrial development, less than 500 acres of Louisiana’s coastal prairie remain. In 2002, USGS botanist Larry Allain, Louisiana Department of Wildlife and Fisheries Natural Heritage ecologist Pattie Faulkner, and U.S. Fish and Wildlife Service GIS specialist Robert Greco teamed up to calculate the acreage of known remnants of coastal prairie. Using Global Positioning Satellite coordinates, 1998 aerial photography, and extensive groundtruthing, the approximate acreage of each known remnant was calculated. We classified remnants, based on vegetation, as either upland or wet. Wet prairie is characterized by soils that are saturated for extended time periods and is dominated by plant species with a wetland affinity (e.g., switchgrass and eastern gammagrass). Upland prairie is dominated by more upland plant species (e.g., little bluestem and slender bluestem grass). In 2010 newly discovered prairie remnants were added and coverage was estimated from ground measurements.