I teased the roots to free up several of the iris rhizomes and mystery plant "rhizomes". The iris is definitely not tridentata. I'm guessing fulva, now. Those rhizomes are just classic Louisiana type. http://www.badbear.com/dkramb/IRIS2.JPG Another plant I remember trying in my pond was Helonias bullata, but I don't think that's it. http://www.badbear.com/dkramb/WTF3.JPG Thanks for helping me brainstorm! Maybe the new pics will be more helpful?