Marty’s photo of the day #4104: I photographed these unusual flowers last month, along the Judith River in the American Prairie Reserve (Montana). Note that they have both green and purplish petals. My wife and I went through multiple books and websites that featured Montana wildflowers and couldn’t come up with an ID, but I know some brilliant follower of my posts will figure it out.

I will post an update when I have an ID.

***Thanks to a reader, I have an update: it’s a trifid bur-marigold.