Might be a North American native, but some of the weedy Polygonum's are not. If you want to know the species it could probably be determined from clear closeups of the flowers and stems.

Well, my "Gay Butterflies" has been blooming for about a week now, and low and behold, it's light orange. I too also have the regular orange tuberosa. I can feel your pain, lol. I had purchased my seed from Swallowtail Garden Seeds. There are some soon-to-be-blooming stalks and the foliage looks a bit different. I'm hoping I'll see some red. If I'm fortunate enough to get red, I'd gladly save you some seed ;) But, that's a big if at this point. I had purchased A. incarnata "Soulmate", which is supposed to be a deep rose pink, yet it bloomed light pink. I also purchased "Red Swamp Milkweed" seed from Pinetree, supposed to be pink to purple (their picture shows a beautiful purple), and of course it bloomed (what else?) light pink. My A. syriaca just bloomed too, light pink! Now I really hate light pink!!!!!!!!!!!! I have loads of A. incarnata "Cinderella", which is what, light pink... It's frustrating indeed...

Not invasive for me, maybe it is the cold here? I planted out HOS's but last year I was given the advice to wait until they are a couple inches high or so. I bet you can search for my old post. I have some coming back from last year but not all of them. I think for some people they are invasive but this has never happened to me. I sowed more this year and plan to transplant them into small pots to give some growing room. I did HOS last year directly in the garden and they did just fine. (they were 2 inches tall or so) Good Luck!

If you have Buckeye butterflies there, they will LOVE your Autumn Fire. I often see a dozen or more at a time on both my Autumn Joy and Autumn Fire which are very similar. I also see lots of teeny butterflies (don't know their name) and I think I've seen Painted Ladies on my sedum too. Your member page doesn't say what state you live in but if you need drought tolerant plants you'll love it. They're easy to grow and easy to root and look good all through the summer and fall. The foliage looks nice before and after they bloom. You will probably need to pinch them back in the spring after they mature to keep them from getting floppy. If you leave the dried flower heads on, they'll give you some winter interest too. The drawbacks are, they don't attract swallowtails or monarchs and they don't bloom for an extremely long time or at least they don't have nectar for an extremely long time. They also attract wasps but those are somewhat fun to watch too. I stand pretty close to mine and they haven't come after me yet. The link below has good photos of brushfoot butterflies and includes the Buckeye and Painted Lady Here is a link that might be useful: Brushfoot butterflies - Wild Utah