Rosa palustris and the first F2 to bloom from bracteata X (rugosa x palustris)

First picture shows Rosa palustris topping out at around 7 feet tall (see yardstick in the foreground)after being hacked back pretty hard last year. It's just starting to bloom. Second picture is close-up of the bloom. I included these two pictures because the first F2 from Rosa bracteata X (rugosa x palustris) is in bloom and it sure takes after palustris a lot. Makes me wonder if it might be a backcross to palustris.

Below is that F2 seedling. See the foliage that looks a lot like palustris. The flowers are a lot like palustris too but a little more pale. If I didn't know it, I wouldn't even suspect bracteata was a part of this one's ancestry - not much apparent influence from that species is showing. And the rugosa part isn't really obvious either.