Here are some USGS Web pages with more information on ferns and fern allies and Anywhere:
Salvinia molesta, Salvinia weevil, Savinia minima
Life history and identification of Salvinia species, a floating, rootless tree fern and a noxious aquatic weed. Site includes posters, instructions on submitting sightings, how to subscribe to a listserv on the weed, and a bibliography.
(Score: 0.690)
Definition:
Any of numerous flowerless, seedless vascular plants having roots, stems, and fronds and reproducing by spores. [American Heritage Dic. of the English Language, 4th ed.]
