Smaller, narrower leaves than its larger relative. It is truly prairie, not requiring as much water as the Common Sunflower.
When in doubt, one way to distinguish the Prairie Sunflower from the Common is that the sepals tend to cup the base of the flower. The sepals on the Common are flat and tend to curl away from the flower.
Small, narrow leaves.
Hit their peak in middle to late August. The pink plants are Rocky Mountain Bee Plant.