Stems to 1.5 m, glabrous and shining, often glaucous or purplish, varying to finely puberulent; cauline lvs narrowly oblong or lance-oblong to narrowly triangular, the larger 10-15 cm, glabrous or finely puberulent (especially along the midvein) beneath; infl 1-3 dm, with erect or strongly ascending branches, often glandular; cal 3-7 mm at anthesis; cor 1.5-3 cm, white or very faintly suffused with violet, usually marked with purple lines inside, the tube abruptly and strongly dilated into a wide throat; anthers pubescent or sometimes glabrous; 2n=96. Moist open woods and prairies; N.S. and Me. to Minn. and S.D., s. to Va., Ala., and Tex. May-July. (P. alluviorum and P. deamii, with relatively small fls and often puberulent stems)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
This species is somewhat frequent throughout the state in both moist and dry soils in various habitats. It often forms large colonies, especially in fallow fields in the Illinoian drift area where it is most frequent.