I wouldn't let anything go to seed that I couldn't identify/

Lobelia inflata, a good plant imo

I have never let mine go to seed. You may not have noticed the tiny flowers. Check to see if it is something you want, if not pull or at least cut the seed pods off.

Peren.all, I've tried direct sowing them a couple times with no germination, so I have no experience with inflata, so I'm just wondering how easy it is to pull up the seedlings, if it did go to seed? I think it be easy, like pulling up hewelweeds? After seeing some of the rarer and more beautiful native Lobelia like kalmii, puberula, ect, inflata becomes quite bland in comparison.

Pretty easy I would say Jay, I was able to just pull them, no digging required. Some had seeded in and I let them be and must have missed getting them before they went to seed. I had quite a few the next year! I did end up pulling them all. I will have to keep my eyes open for L. kalmii and grab a seed pod if possible. Odd that L. puberula is shown both north and south of me but not in my area.

I have hundreds of siphilitica, both blue and white. I adore them but if I do not get them before they seed I have thousands! Cardinalis is my favorite of them, it never wants to stay where I want it so I let it grow any where it wants!