Golden bee-plant

Cleome platycarpa Torrey in C. Wilkes et al., U.S. Expl. Exped. 17: 235, plate 2. 1874; Celome platycarpa (Torrey) Greene

Annuals, 10-60 cm. Stems densely branched basally; purple-tinged; glandular-pubescent. Leaves: (stipules scalelike, minute, obscured by pubescence); petiole 1.5-4.5 cm; leaflets 3, blade flat, ovate to obovate, 1-3.5 × 0.5-1.3 cm, margins serrulate-denticulate or entire, apex obtuse, surfaces glandular-pubescent. Racemes 1-3.5 cm (5-40 cm in fruit); bracts unifoliate, obovate to spatulate, 3-25 mm. Pedicels 7-17 mm. Flowers: sepals deciduous, distinct, yellow, awl-shaped, (3-)4-5(-6) × 3-7 mm, margins entire, densely glandular-hairy; petals golden yellow, oblong, 6-12 × 0.3-0.4(-0.6) mm; stamens yellow, 10-17 mm; anthers 1.8-2 mm; gynophore 10-18 mm in fruit; ovary (compressed), 3.5-5 mm; style 1-3 mm. Capsules (pendent) not inflated, 12-25 × 8-12 mm, striate, (glandular-pubescent). Seeds 10-20, brownish black, spheroidal, 3-3.2 mm, (glossy) smooth. 2n = 40.

Flowering summer. Alkaline clay soils, volcanic tuff, dry foothills, among junipers, in sagebrush scrub, fields, railroads; 800-1200 m; Calif., Idaho, Nev., Oreg.

Peritoma platycarpa resembles some species of Cleomella in the absence of a nectary-disc, shape of the replum, and indument.