As a comment about
Wild Blue Phlox (Phlox divaricata),
jmorth wrote:
Common wildflower in Illinois and Indiana found in partial shade of rich, moist or rocky woodlands. Often in patches or colonies along streams. Perennial root system is tough, fibrous, and stringy. Flowers noted for their color, beauty, and fragrance.
Pioneers made a leaf tea to treat eczema and to purify the blood. A root tea was used to treat venereal disease.