The presence of this noxious little weed is nobody's fault but my own. Years ago (probably 1980s) I brought a couple of specimens home from the woods. They appeared to be a terrific addition to my rock garden. Actually this stuff performed superbly by forming little mats along the edges of the elevated rocks, then growing over the edges a bit. The flower stems (up to about 2" high) emerged along the outer edge of the mats, presenting just the effect I dreamed of with their tiny blue flowers. The stems never emerge from the inner portions of the mat.
Then one day I decided I wanted a pond with fishies right where the rock garden was located (not far from an outlet). So of course that excess soil had to be moved to another location and the rest is history.
