Herbs, erect or ascending, rarely rooting at nodes. Stems 5--90 cm; internodes glaucous, glabrous. Leaves spirally arranged, sessile; blade linear-lanceolate, 5--50 ´ 0.2--3 cm (distal leaf blades equal to or narrower than sheaths when sheaths opened, flattened), apex acuminate, glaucous, glabrous. Inflorescences terminal, often axillary; bracts foliaceous. Flowers distinctly pedicillate; pedicels 0.8--3 cm, glandular-puberulent, rarely glabrous or glabrescent; sepals 4--11 mm, glandular-puberulent, usually with apical tuft of eglandular hairs, occasionally with scattered eglandular hairs among glandular, rarely glabrous or glabrescent; petals distinct, bright blue to rose or magenta, broadly ovate, not clawed, 6--16 mm; stamens free; filaments bearded. Capsules 4--7 mm. Seeds 2--4 mm. All of the chromosome counts cited by E. Anderson (1954) for this species are attributable to Tradescantia occidentalis var. occidentalis.
Stem slender, straight, often branched, 2-6 dm at anthesis, glabrous and glaucous; lvs firm, glabrous, involute, usually narrowly linear and under 1 cm wide; bracts like the lvs; cymes solitary and terminal, or with another one peduncled from an upper node; pedicels and sep sparsely pubescent with glandular hairs 0.5 mm; sep acute to acuminate, 6-10 mm; pet rose to blue, 12-16 mm; 2n=12, 24. Dry prairies and plains; w. Wis. and Minn. to La., w. to Mont., Utah, and Tex.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.