Thank you! I think you are right; I was wracking my brain trying to remember what I might have planted last year (several things have emerged after seeming to die, which I had forgotten about) and I think there WAS a baptisia among them. I am sure you're right, matter of fact. I'll have to try to find what kind exactly.
I was pretty sure it wasn't "just a weed."
And googling quickly, I now recall I did plant Baptisia australis, or blue false indigo!