Pioneers heading across the Iowa prairies in the mid-1800s before roads existed might have looked for this plant called a compass plant that has leaves oriented in a north-south axis. Somehow they became aware of this marvelous plant with yellow flowers and how it could guide them in their travels.
It is a member of the sunflower family that can grow 12-15 feet tall by late summer, with a taproot of 12-15 feet. Below is another view of this amazing perennial, which does not produce flowers until after the second or third year of growth.