Stuckenia vaginata

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Stuckenia vaginata, commonly called sheathed pondweed, is a fully submerged aquatic plant that lives in fresh and brackish water. It occurs across Europe, northern Asia (except China), and North America, and it is considered rare. It has no floating or emergent leaves; all of its leaves grow underwater. The plant flowers are wind-pollinated and its seeds float. Tubers rich in starch form on its underground rhizomes. It can reproduce vegetatively through tubers and plant fragments or sexually via seeds. A key difference between Stuckenia and the related Potamogeton group is that in Stuckenia the stipule is attached to the leaf base and comes away with the leaf sheath when pulled, like a grass sheath. Stuckenia vaginata grows from 1 to 4 meters long and has long, narrow, linear leaves with long stipule sheaths. It belongs to the order Alismatales and the family Potamogetonaceae.