23. Lepidium latifolium Linnaeus, Sp. Pl. 2: 644. 1753.
Cardaria latifolia (Linnaeus) Spach
Perennials; (rhizomes thick, caudex woody); glabrous or pubescent. Stems simple from base, erect, branched distally, (2-)3.5-12(-15) dm. Basal leaves not rosulate; petiole 1-9 (-14) cm; blade elliptic-ovate to oblong, (2-)3.5-15(-25) cm × (5-)15-50(-80) mm, (leathery), margins entire or serrate. Cauline leaves sessile or shortly petiolate; blade oblong to elliptic-ovate or lanceolate, (1-)2-9(-12) cm × 3-45 mm, base cuneate, not auriculate, margins serrate or entire. Racemes (subcorymbose panicles), slightly elongated or not in fruit; rachis glabrous or sparsely puberulent, trichomes straight, cylindrical. Fruiting pedicels ascending to divaricate, straight or slightly curved, (terete), 2-5(-6) × 0.1-0.2 mm, glabrous or puberulent adaxially. Flowers: sepals suborbicular to ovate, 1-1.4 × 0.8-0.9 mm; petals white, obovate, 1.8-2.5 × (0.8-)1-1.3 mm, claw 0.7-1 mm; stamens 6; filaments 0.9-1.4 mm, (glabrous); anthers 0.4-0.5 mm. Fruits oblong-elliptic to broadly ovate or suborbicular, (1.6-)1.8-2.4(-2.7) × 1.3-1.8 mm, apically not winged, apical notch 0(-0.1) mm deep; valves thin, smooth, not veined, glabrous or sparsely pilose; style 0.05-0.15 mm, exserted beyond apical notch (when present). Seeds oblong, (0.8-)1-1.2 × 0.6-0.9 mm. 2n = 24.
Flowering Jun-Sep. Pastures, grasslands, disturbed places, fields, roadsides, slopes, saline meadows, stream banks, waste grounds, dry flats, sagebrush and pinyon-juniper communities, barren hillsides, ditch banks, edge of marshes; 0-2500 m; introduced; Alta., B.C., Que.; Ariz., Calif., Colo., Conn., Idaho, Ill., Kans., Mass., Mo., Mont., Nebr., Nev., N.Mex., N.Y., Oreg., Tex., Utah, Wash., Wyo.; s Europe; Asia; n Africa; introduced also in Mexico (Durango, San Luis Potosí), Australia.