Thanks Maryl. Hetty IDed it for me and it IS an invasive from Asia:
THANK YOU, Hetty!
We were all stumped and as I feared, it is an import that spreads seeds by air. No wonder I have so many growing in my front garden bed!!! Yikes!!
Here is some interesting read about it:
http://www2.fiu.edu/~kopturs/p...
