Gentianella amarella (L.) Börner
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Plants 1.5–6 dm, seldom branched; lvs sessile, lanceolate or lance-ovate; fls solitary in the middle axils, several in a close cyme from the upper axils, the pedicels seldom 1 cm; fls 4–5-merous; cal-lobes linear-oblong, 3–5 mm; cor blue or bluish, 10–15 mm, tubular funnelform to subsalverform, the obtuse or acute lobes 3–5 mm, bearing at base a fringe of hairs 2 mm; 2n=36. Moist rocky or gravelly soil; interruptedly circumboreal, s. to Me., Vt., w. S.D., and Mex. July, Aug. (G. acuta; Gentiana amarella) Highly variable, with some geographic correlation, but only doubtfully divisible into vars.
northern gentian, felwort