Rigid Goldenrod
Oligoneuron riddellii
From what I've read, Goldenrods are one of the best caterpillar host plants. In the photos, you can see they are also popular with the adult pollinators.
The old Lakota was wise. He knew that man's heart away from nature becomes hard; he knew that lack of respect for growing, living things soon led to lack of respect for humans too.
Chief Luther Standing Bear