Salvinia minima (aquatic plant, fern)

Ecology Distribution Management Info Impact Info References and Links Contacts

Management Information Mechanical: S. minima is vulnerable to conditions of salinity. In central North America along coastal sites, S. minima is found only during wintertime, when freshwater outflow is high and salinity measurements decline to 4 - 7 ppt. S. minima is regularly controlled by opening gates to allow saline water from the Gulf of Mexico into the bayous (Jacono, 2003). If the water level can be dropped several feet, research has shown that this has a proven effect at salvinia control. However, in order to be effective, water levels must remain low long enough to allow for the desiccation or freezing of stranded plants (McKinney and Durocher, Undated). Booms and other barriers may be useful in confining infestations or restricting entry into sensitive areas. However, in areas with significant current or wind action their utility is limited without frequent clearing and maintenance since plants will accumulate against barriers until pressure forces them over or under the barrier (McKinney and Durocher, Undated). Chemical: The following herbicides have been reported giving successful control of S. minima with multiple treatments: Diquat, Fluridone, and Glyphosate. Unfortunatly, due to the extremely large number of individual plants that can be present, applying herbicide to each plant is difficult. The dense pubescence on the leaf surfaces can negatively impact the effectiveness of certain types of herbicide applications. These thick hairs can impede herbicide penetration when using any type of foliar spray application. (McKinney and Durocher, Undated). Biological: Cyrtobagous salviniae is an accidentally introduced species found primarily in Florida. Scientists have hypothesized that the presence of the C. salviniae in Florida may account for the less aggressive growth of S. minima in this area, when compared to troublesome growth that occurs in Texas and Louisiana where the weevil is not found (Center et al. 2001).              Location Specific Management Information Texas All Salvinia species are on the state's "Harmful or Potentially Harmful Exotic Fish, Shellfish, and Aquatic Plants" list, which means they are prohibited in the State of Texas (McKinney and Durocher, Undated). S. minima is vulnerable to conditions of salinity. In central North America along coastal sites, S. minima is found only during wintertime, when freshwater outflow is high and salinity measurements decline to 4 – 7 ppt. S. minima is regularly controlled by opening gates to allow saline water from the Gulf of Mexico into the bayous (Jacono, 2003).          Management Resources/Links 1. Center, T.D., Davern, T.R., and Jacono, C.C. 2001. The adventive status of Salvinia minima and S. molesta in the Southern United States and the related distribution of the weevil Cyrtobagous salviniae. Castanea 66 (3): 214-226. 2. Jacono, C.C. 2003. Salvinia: Salvinia minima - Common Salvinia Nonindigenous Aquatic Ferns in the United States (Salvinia molesta - Salvinia minima ) and their Biological Control, Cyrtobagous salviniae, the Salvinia Weevil - USGS.         Summary: Available from: http://salvinia.er.usgs.gov/ [Accessed 26 April 2006] 3. McKinney, L. D., and P. P. Durocher. Undated. Aquatic Vegetation Management In Texas: A Guidance Document. Texas Parks & Wildlife Department INLAND FISHERIES.          Results Page: 1