Potamogeton pusillus L.: Narrowleaf pondweed, small pondweed, baby pondweed. Potamogetonaceae (pondweed family). Native perennial/annual. Growing submersed, from fibrous roots, or rarely very slender rhizomes, in ponds and streams. Has numerous submersed leaves of a single shape; there are no floating leaves. The slender, sometimes flattened, much-branching stems are held erect underwater, to 3.3 ft (1 … Continue reading Narrowleaf Pondweed