I once stole this plant from a ditch at the community College. No really, I really did do that. I wasn't arrested either. It almost tops the time I took cattail from the ditch at the hospital. I wasn't arrested then either.
Actually I didn't know what this was until it made a pretty white flower, and now I love it. I had wanted to buy duck potato because I had read that it's edible to, well, ducks. Possibly rabbits? Not sure. But now that I have this plant, all I have to do is propagate it, and I will have unlimited duck food! Mwa haha.
Supposedly the underground tubers are eaten by ducks and snapping turtles. It sounds like a great plant to grow. Supposedly it can be propagated by transplanting the tubers. Also supposedly, it was a major food source for the Native Americans that lived in the Okeechobee area.