Bottle or Closed Gentian
Gentiana clausa
is a 1'-2' tall flowering plant in the Gentianaceae family. It is native to Eastern North American moist meadows and woods at higher elevations, from Quebec in the north, through the Appalachian range to North Carolina and Tennessee in the south. It has paired, lanceolate leaves, usually on unbranched stalks, and blue blooms which remain closed or nearly so (thus the Latin specific name). It flowers from late August to October.
Gentians are named after King Gentius of Illyria who is credited with discovering medicinal properties of the root. The flowers do not open and are pollinated by insects that are strong enough to force their way in.
For medicinal uses and description see Henriette,s Herbal