Lepidium austrinum
Fl. S.E. U.S., 468, 1331. 1903.
Annuals or biennials; often densely hirsute, (trichomes cylindrical). Stems often simple from base, erect, branched distally, (1.5–)2–6.7(–9.4) dm. Basal leaves (later withered); rosulate; petiole (0.7–)1.5–4.5 cm; blade pinnatifid, 2–8.3 cm × 9–26 mm, margins (of lobes) entire or dentate. Cauline leaves shortly petiolate; blade oblanceolate to nearly linear, 1–4.5(–6.2) cm × 3–10(–17) mm, base attenuate to cuneate, not auriculate, margins entire or dentate. Racemes much-elongated in fruit; rachis pubescent, trichomes curved, with fewer and longer, straight ones. Fruiting pedicels usually divaricate, rarely horizontal, straight or slightly recurved, (terete), (2.5–)3–4.1(–4.7) × 0.2 mm, puberulent adaxially. Flowers: sepals oblong, 0.8–1 × 0.2–0.4 mm; petals (sometimes absent), white, oblanceolate, 0.4–1.6 × 0.1–0.8 mm, claw absent; stamens 2, median; filaments 0.8–1 mm; anthers 0.1–0.2 mm. Fruits elliptic-obovate to obovate-orbicular, 2.4–3.2 × 1.8–2.5 mm, apically winged, apical notch 0.2–0.5 mm deep; valves thin, smooth, not veined, sparsely puberulent, (trichomes often antrorsely appressed, sometimes restricted to margin); style 0.05–0.1 mm, included in apical notch. Seeds ovate, 1.4–1.6 × 0.7–0.9 mm.
Phenology: Flowering Mar–Jun.
Habitat: Disturbed grounds, railroad tracks and embankments, fields, knolls, stream banks, waste areas, open banks, roadsides, sandy terraces
Distribution
Kans., La., Miss., N.Mex., Okla., Tex., Mexico (Coahuila, Nuevo León, San Luis Potosí).
Discussion
Selected References
None.