A few people thought it was a weed, the guy it was from really didn't know. I looked through my weeds of north central states book and couldn't find it. Now it is getting some sort of purple flowering along the stem near the top. Any ideas?

I have since found a patch of it growing elsewhere on my property near our tenant's house. Although our tenant teaches ecology he has no idea what it is and couldn't remember if it flowered or anything, although he knows it has been there for 3 years. ? Please advise if this is a weed or "real plant" and of course a name would be nice.

Thanks, Marcia

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