Mojave cottonthorn, more...
Shrubs, 30-120 cm. Stems 1-5+, erect, spiny, pannose but for tomentose to glabrescent streaks. Leaves: primaries forming straight, ascending spines, 20-30 mm; secondaries oblanceolate to spatulate, 10-30 mm, tomentose to sericeous. Heads 4-7. Peduncles 5-12 mm. Involucres turbinate, 8-10 mm. Phyllaries 4-5, narrowly ovate. Florets 4-5; corollas pale yellow, 10-12 mm. Cypselae 5-8 mm, densely pilose or villous; pappi of 100-150 bristles 9-12 mm. 2n = 60. Flowering spring-summer. Sandy and gravelly places, Joshua tree woodlands, creosote bush scrub; 600-1500 m; Ariz., Calif., Nev.
Plant: shrub, < 12 dm, spiny; stems unevenly tomentose, becoming ± glabrous in stripes below spines Leaves: alternate and generally clustered in axils; main leaves 2-3 cm, tomentose or becoming glabrous, forming ± straight spines; clustered leaves 10-30 mm, ± oblanceolate, tomentose or silvery-hairy INFLORESCENCE: primary inflorescence a head, each resembling a flower; heads discoid, generally 4-7, axillary or in ± rounded, terminal clusters; peduncles generally 5-12 mm, tomentose, bracts 0; involucre 8-10 mm, narrowly obconic; phyllaries (4)5, narrowly ovate; receptacle naked Flowers: (4)5; corollas 10-12 mm, pale yellow, lobes long, spreading; anther bases ± sagittate, tips obtuse or acute; style branches papillate to short-bristly, tips truncate to conic Fruit: achenes, 5-8 mm, ± short-soft-hairy, obconic or fusiform, often angled; pappus of many fine bristles, 9-12 mm Misc: Joshua-tree woodland, creosote-bush scrub; 600-1500 m.; May-Aug