re: Water Hybiscus (Hibiscus Coccineus)...pretty sure, unless
someone else knows for sure.
The stems & leaves also look like it.
It's tall (mine gets up to 8ft), deciduous, grows in shallow water or bog.
It produces seed pods, and I've had several volunteer around
our little pond where it has happily lived for the past 10yrs (at least).
I originally found one by accident at a place that sold pond plants,
and bought a ~30lb clump of it. It may be in nurseries, but haven't looked.
Easy to grow. Highly recommend it.
Here's a good article
