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Salvinia molesta

Giant salvinia

Photographer: Keith Bradley
Source: Botanist/Conservation Biologist,


Salvinia is a rootless, floating aquatic fern. Emergent groups of leaves (fronds), oblong and flat (smaller growth forms) or semi-cupped/folded (larger growth forms), grow in chains and float on the water surface forming dense mats. Leaves grow in pairs and grow to approximately 1/2 inches wide and 1 inch long. Brown, thread-like leaves hang underwater, joining at a node along a horizontal, underwater stem and are similar in appearance to a root system. The upper surface of the green leaves is covered with rows of white, coarse hairs, acting as a water repellent. The hairs of giant salvinia are joined at the tips in an egg beater shape.

If you believe you have found giant salvinia in Texas, please report it here.

Photographer: Barry Rice,,

Close-up of the fern frond, showing the "egg beater" shape of the hairs on the upper surface.

Photographer: Ted D. Center, USDA Agricultural Research Service,

Extensive infestation covering the entire surface of this body of water.