7. Caulanthus crassicaulis (Torrey) S. Watson, Bot. U.S. Geol. Survey 40th Parallel 5: 27. 1871; Streptanthus crassicaulis Torrey in Stansbury, Exped. Utah 383. 1852. TYPE: United States, Utah, mountains W shore of Great Salt Lake, 30 May 1850, H. Stansbury s.n. (lectotype designated by Payson (1923: 292), NY!).

Caulanthus crassicaulis var. glaber M. E. Jones, Zoe 4: 266. 1893; C. glaber (M. E. Jones) Rydberg, Fl. Rocky Mts. 364. 1917. TYPE: United States, Utah, Summit near Sink Valley, 7000 ft, 23 Jun 1890, M. E. Jones s.n. (holotype, POM!).

Caulanthus senilis A. Heller, Muhlenbergia 8: 137. 1913. TYPE: United States, Nevada, Mineral Co., lower slopes of White mountains, 7500 ft, 25 Jun 1912, A. A. Heller 10506 (holotype, RENO; isotype, NY!).

     Herbs, perennial, with a woody caudex, glabrous or sparsely pubescent with simple trichomes, glaucous. Stems 2–10 dm, erect or ascending, simple or rarely branched, glabrous or rarely sparsely pubescent, hollow, strongly inflated and to 3 cm in diam. at the middle. Basal leaves rosulate; petiole 0.5–9 cm; blade obovate to oblanceolate in outline, 1–12 x 0.3–4.5 cm, glabrous or sparsely pubescent, margin entire, dentate-sinuate, lyrate, runcinate, or pinnatifid; uppermost cauline leaves short petiolate, linear to narrowly oblanceolate, entire. Racemes with a terminal cluster of sterile flowers, ebracteate, densely flowered, elongated in fruit; fruiting pedicels ascending, 1–5 mm, glabrous or pubescent with flattened trichomes. Sepals creamy white, purplish, or greenish, ovate to lanceolate, 7.5–14 ´ 2.5–4 mm, erect, equal, not keeled; petals brown or purple, 10–15 mm; blade 3–5 x 1.2–2.5 mm, not or hardly crisped; claw oblanceolate, 7–10 x 2—2.5 mm; filaments tetradynamous, free, median pairs 3–8 mm, lateral pair 2–7 mm; anthers narrowly oblong, 3–6.5 mm, equal; ovules 98–126 per ovary. Fruits 4.5–14 cm ´ 2–2.5 mm, erect to ascending, terete or slightly latiseptate; valves with an obscure midvein; style obsolete or rarely to 0.6 mm; stigma strongly 2-lobed, lobes to 1 mm, connivent, opposite valves. Seeds 1.5–4 x 1.5–2 mm; cotyledons entire.

Flowering: Apr–Jul.

Habitat: sagebrush scrub, pinyon-juniper woodland.

Elevation: 1200–2900 m.

Distribution: United States (N and W Arizona, E-C California, NW Colorado, S Idaho, Nevada, Utah, SW Wyoming).