There are several species of the gentian family that grow in Eastern North America. As its name indicates this species has paired very slender leaves, the major distinguishing feature. The flowers are vase-like with fused petals and occur in clusters at the top of the stem. They are blue and violet and sometimes white in color. The flower lobes are rounded on the top. Some gentian species remain closed. This one normally has a narrow opening, though it may sometimes be closed. Pollinating insects must be strong enough to push their way through the opening. This makes the bumblebee a common pollinator.

The plant grows 6-24 inches tall in wet meadows, bogs, wet conifer, and mixed conifer-hardwood woodlands.  Another common name for the narrow-leaved gentian is bog gentian. This species is found from Lake Superior to Labrador and south, mostly in the mountains, to West Virginia. There are small local populations in the mountains of Tennessee in Virginia.