how far have you gotten on your analysis???? i hate doing someone elses homework or project ... but wouldnt mind pointing out a wrong presumption in a sequence of thought as to ID ... ken

I agree with floral_uk; it does look like loosestrife. here in Oregon is is a noxious weed that carries disease. Without being able to see it up close, it's tough to be sure. It is a possibility that it might be Epilobium (fire weed), but the shape of the inflorescence leads me to believe it's Lythrum salicaria.

Thank you Kristin for your advise. I plant only non-invasive species in my garden so I am going to plant the new butterfly Molly (dwarf the non-invasive one) instead - it has similar look and flowers and it is the most compact out of all the butterfly bushes and supposedly non-invasive. Here are some photos from my garden. Love to mingle with nature and study all the deer resistant non-invasive species and help others with my gardening experience. Happy gardening season!. :-) Eva

Leucanthemum vulgaris, the meadow ox eye daisy type, would have a basal rosette, and they don't grow rhizomes (IME). Symphyotrichum (aka Asters), would be my bet too, I planted/ handled some several times, this foliage reminds me of S ageratoides, only problem there are several species, sub-species and cultivars, so really tricky to be sure which it is, plus I have no clue whether they could prosper without winter dormancy, good luck, Lin