I took those pics after evicting some volunteers from my Mom's yard. That was a lovely novelty potted plant when we lived in OH, but not welcome here after she got an outbreak of it all around her yard from one potted plant. You're in the same zone as me, Kathy. Probably hardy where you are too if it gets loose in the ground (so I would trim the bloom things off, if it makes any, so it won't then make berries that drop & are moved by birds all over the area & sprout.)
You could (carefully, so the thorns don't get you) feel around the base of your plant and see if it feels like more than 1 area where the leaves are emerging. If so, you should be able to unpot & pull them apart.
