McDude,I can't believe how invasive that stuff is.There is a rafting area a mile upwind from us and it's loaded with milfoil.The boat traffic dislodges it and a lot of it ends up around my beach and dock.It requires constant attention and if I miss a strand it takes root pretty quickly.It even grows on shore! If it washes up on the beach it will root within a week and each 12' strand will sprout 4 or 5 new plants.I've also noticed that if it remains in the water it will sink after a few days and take root on the bottom.It's like some creature from a cheap science fiction movie.I have nightmares about thousands of slimy milfoils invading my house at night and strangling me as I sleep.