You want to hear something real crazy??? Last fall I was on my last mowing for the year and as always I had my mower set as low as I can get it ,And while driving by my lily beds I said , What If? And guess what I did next? ___Yes I did" I got on my beds one by one and mowed my day lily's down to the dirt! some of the clumps you cold see the roots! I didn't sleep all last winter worrying about them!, But guess what ? This year they came back with a vengeance! I don't know what the moral of this story is but I'll never do it again!!