I have a bunch of the old fashioned ditch lilies that were sent to me in a trade about three years ago. They bloomed last year and have taken off and started spreading like crazy this year. I want them gone and plan to dig out what I can and use brush killer on the ones I cannot get to with my shovel ( they have migrated to the neighbors through the chain link fence). Any other advise you can give on this matter would be greatly appreciated!