my thoughts were ... since daylilies are historically invasive, at least in part, and considered in the weed category in Asia, perhaps this luscious green that the water hyacinths is emitting is a beacon to action. Could be, if invasive, it needs to be brought forth to attention and reinvented as we struggle to contain and transform its damage into more beneficial forms?
Self contained ponds sounds right. :D
... reminds me that I need to go pull out the rest of the primrose and foxtail in my garden ... the first was a pretty but overwhelming presence, the second a dangerous and persistent reseeding threat to my dogs' noses and lives ... helpful to learn about all these things ...
So, thanks for the educational banner that is also so easy on the eyes, and the educational question about its possible growing habit and status as invasive!