Stems stout, smooth, I to 2 feet high, and usually unbranched, from a perennial root. Leaves opposite, ovate to lanceolate, three to seven-nerved, pointed at the apex, narrowed or rounded at the sessile base, rough-margined. Flowers 1 to 11/2 inches high, sessile in dense, terminal clusters and usually with one or two in the axils of the upper leaves. Each flower with two bracts beneath the calyx. Calyx lobes five, ovate-lanceolate, ciliate, somewhat spreading. Corolla blue, rarely white, club-shaped, nearly or quite closed at the summit, its lobes indistinct, the intervening appendages very broad and light colored. Stamens five, their anthers united into a tube.
Memoir 15 N. Y. State Museum
Closed Blue Or Blind Gentian - Dasystephana andrewsii
In moist soil and damp thickets, Quebec to Manitoba, south to Georgia and Nebraska. Flowering from late in August to October.
The Soapwort Gentian (Dasystephana saponaria (Linnaeus) Small) closely resembles the Closed Gentian, but the leaves are usually pointed at each end and the corolla lobes distinct, and longer than or equaling the intervening plaits. The Yellowish Gentian (Dasystephana flavida (A. Gray) Britton) has a greenish or yellowish white corolla, distinctly open at the summit, and ovate-lanceolate leaves.
The Narrow-leaved or Bog Gentian (Dasystephana linearis (Froelich) Britton) possesses an open, blue corolla and linear-lanceolate leaves. These, together with the rare Gray's Gentian (Dasystephana grayi (Kusnezow) Britton), are all natives of New York, but not so common as the Closed Gentian, although the Narrow-leaved or Bog Gentian is frequent in the Adirondacks.