Rigid Goldenrod
Oligoneuron riddellii
Notes:
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.
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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