Biennials or perennials; short-lived; apomictic; caudex present or absent. Stems usually 1 per caudex branch, arising from center of rosette near ground surface, 1.5-6 dm, densely pubescent proximally, trichomes sessile, 2-4-rayed, 0.15-0.4 mm, usually sparsely pubescent distally, rarely glabrous. Basal leaves: blade oblanceolate, 1.5-6 mm wide, margins usually entire, rarely denticulate, ciliate proximally, trichomes (simple), to 0.5 mm, surfaces sparsely to moderately pubescent, trichomes sessile, 3-5 (or 6)-rayed, 0.15-0.35 mm. Cauline leaves: 2-20(-38), often concealing stem proximally; blade auricles 0.3-2 mm, surfaces of distalmost leaves sparsely pubescent or glabrous. Racemes 5-20(-36)-flowered, usually unbranched. Fruiting pedicels erect to ascending, usually straight, 3-10 mm, pubescent or glabrous, trichomes appressed, branched. Flowers ascending at anthesis; sepals pubescent; petals white or lavender, 5-7 × 0.9-1.3 mm, glabrous; pollen spheroid. Fruits ascending, not appressed to rachis, not secund, straight, edges parallel, 2.5-7.5 cm × 1.2-1.8 mm; valves glabrous; ovules 46-100 per ovary; style 0.3-1 mm. Seeds uniseriate, 1.8-2.2 × 1-1.4 mm; wing continuous, 0.1-0.4 mm wide.
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