Herbs 25-90 cm tall, perennial. Roots tuberous. Stems erect, unbranched or branched above, ribbed, unwinged, with sparse long multicellular hairs apically mixed with sparse felt. Leaves discolorous, surface smooth, abaxially white and densely felted, adaxially green and with sparse multicellular hairs. Lower cauline leaves petiolate; leaf blade lanceolate to elliptic-lanceolate, 6-20 × 2-3 cm, undivided, fringed with ca. 1 mm spinules, apex obtuse to acuminate. Middle and upper cauline leaves similar but auriculate semiamplexicaul. Capitula 1 to few, corymbose, erect. Involucre narrowly ovoid, ca. 2 cm in diam., glabrous or sparsely cobwebby. Phyllaries imbricate, in ca. 7 rows, lacking marginal spinules, wings, and scarious appendage, abaxially with a dark resinous gland; outer and middle phyllaries triangular to lanceolate, 5-11 × ca. 2 mm, apex acute and tipped with a spinule less than 1 mm; inner phyllaries broadly linear, ca. 2 × 0.2 cm, apex acuminate and scarious. Florets bisexual. Corolla purple, ca. 1.7 cm, tube ca. 7 mm. Achene brownish striate with brown, ca. 4 mm. Pappus bristles ca. 1.5 cm. Fl. and fr. May-Sep. 2n = 28, 34.
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