Ribbonleaf Pondweed, Ribbon-leaf Pondweed, Ribbon-leaved Pondweed
Potamogeton epihydrus
Synonyms: Potamogeton epihydrus ssp. nuttallii, Potamogeton epihydrus var. ramosus
The photo above shows a close-up of ribbonleaf pondweed as seen in one of the slow-draining pools in Swampy Meadows on the western slopes of Mt. Adams...........September 6, 2008.< The submerged stem leaves are much different in shape than the floating leaves as seen here. The submerged stem leaves are long, narrow (but greater than 2 mm) and have a prominent midvein which runs their length (barely visible here).
The photo above shows a close-up of the floating leaves of ribbonleaf pondweed as seen in Swampy Meadows on the western slopes of Mt. Adams..........September 6, 2008.
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Close-ups of the floating leaves of ribbonleaf pondweed as seen in Swampy Meadows on the western slopes of Mt. Adams.........September 6, 2008.
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Ribbonleaf pondweed as seen in a shallow pond in upper Muddy Meadows south of the Muddy Meadows trail...........August 28, 2012. Note the long, narrow submerged leaves and the broader floating leaves.
Paul Slichter