Lysimachia ciliata "Firecracker."

A fairly new plant with very attractive blackish- purple foliage and yellow flowers. I planted a group of three plants in a herbaceous border in 1998. By spring 1999, the plant reappeared three feet from where It was planted. Spring 2000 it had spread 8 ft all round . I had to lift the entire border and painstakingly remove every white root of little horror . Amazingly sharp root tips are designed for pushing their way through the densest clumps of perennial plant and shrub roots. This week I have noticed ......it is back!