Plant Industry - Plant Protection Section

Giant Salvinia

Since November 1998, the noxious aquatic weed Giant Salvinia (Salvinia molesta) has been detected in 20 counties in North Carolina. This floating aquatic fern, native to South America, is an aggressive invader of freshwater lakes, ponds, and slow moving streams. It has a very high growth rate and can double its biomass in less than a week under favorable conditions. It forms thick floating mats that clog waterways and interfere with navigation, irrigation, drainage, and recreational water use. When the mats sink and decay, dissolved oxygen levels can be severely depleted, endangering fish and other aquatic life.

Until recently, all detections of Giant Salvinia in North Carolina had been from aquatic plant nurseries and dealers, botanical gardens, ornamental ponds, or retention ponds, and the weed has been successfully eradicated from these sites. However, in September 2000, naturalized infestations of Giant Salvinia were found in New Hanover County and Pender County. NCDA&CS personnel currently are conducting delimiting surveys to determine the extent of these newly-detected infestations.

Please help us limit the spread of Giant Salvinia in North Carolina. If you see this weed, please contact the local NCDA&CS Specialist in your area or Bridget Lassiter, Weed Specialist NCDA&CS, 1-800-206-WEED.