Floating Pondweed, Floatingleaf Pondweed, Floating-leaved Pondweed
Potamogeton natans

The photo above shows the floating leaves and spike of floating pondweed as seen in a slow-moving stream. The base of the leaves of this species are rounded to cordate (heart-shaped) as seen here.

Floating pondweed as seen in a slow-moving stream.

The photo above shows the floating leaves and spike of floating pondweed as seen in a slow-moving stream.

The photo above shows a close-up of the floating leaves of floating pondweed aas seen in a slow-moving stream. Note again the rounded to slightly heart-shaped base to the leaves of this species.
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The photo above shows a close-up of the floating leaves of floating pondweed as seen in a slow-moving stream.
Paul Slichter