Salvinia Natans

Salvinia natans, commonly called salvinia or water fern, is a deciduous, free-floating, rootless, aquatic perennial fern that forms rapidly expanding mats of foliage (to 1” tall) on still water surfaces. It is distinguished from the similar Azolla filiculoides (mosquito fern) by having longer leaves (to 3/4”) which are unlobed and hairy, simple mostly unbranched stems and no true roots. Leaves are in whorls of three. Two elliptic, light green leaves appear on the water surface and the third leaf (which performs root functions) is heavily dissected and submerged. It is a popular addition to water gardens and ponds. This fern is native to Europe, Asia and northern Africa. Plants in the genus Salvinia are sometimes commonly called water spangles.