Great Basin Naturalist 27: 178. 1967.
Perennials; (cespitose, caudex thick, woody, numerous-branched, with persistent petiolar remains); puberulent. Stems simple or few from base (caudex), erect to ascending, unbranched or branched distally, (0.3–)0.5–1.5(–1.7) dm. Basal leaves not rosulate; petiole 0.3–0.8 cm, (papery); blade linear, (0.5–)1–7(–8) cm × 10–36 mm, margins entire. Cauline leaves sessile; blade linear, base attenuate, not auriculate, margins entire, (similar to basal, smaller distally). Racemes slightly elongated in fruit; rachis puberulent, trichomes straight. Fruiting pedicels divaricate-ascending, straight, (terete), 3–8 × 0.3–0.4 mm, puberulent throughout. Flowers: sepals (sometimes somewhat persistent), oblong-obovate, 1.8–2.8 × 1.3–1.8 mm; petals white to pale yellow, suborbicular to broadly obovate, 3.2–4.6 × 2.5–3.2 mm, claw 0.5–1.5 mm; stamens 6; filaments 1.8–2.6 mm, (glabrous); anthers 0.5–0.8 mm. Fruits ovate, 4–5.5(–6.2) × 3–3.8 mm, apically winged, apical notch 0–0.2 mm deep; valves thin, smooth, not veined, glabrous; style 0.5–1.2 mm, exserted beyond apical notch. Seeds ovate, 2.2–2.8 × 1.4–1.6 mm.
Phenology: Flowering May–Jun.
Habitat: Pinyon-juniper and sagebrush communities, white sandy shale
Elevation: 1800-2000 m
Of conservation concern.
Lepidium barnebyanum is known from the Green River and Uinta Shale Formations in Duchesne County. It is in the Center for Plant Conservation’s National Collection of Endangered Plants.