Plants to 4 m; stem and infl strigose to partly villous or hirtellous; seeds 2-4; self-incompat- ible, with 90+ percent stainable pollen; mainly w. of the Mississippi R., but also common throughout Ill. (G. longiflora)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.