Annuals (viscid and unpleasantly aromatic), 30–100 cm; taprooted. Stems persistently white-tomentose and stipitate-glandular. Leaf blades (crowded, internodes mostly 1–3, sometimes to 10, mm) linear-lanceolate, (2–)4–8 cm × 3–10 mm, bases not clasping, usually (at least the proximal) decurrent 3–10 mm, margins strongly revolute to revolute-undulate, faces bicolor, abaxial densely white-tomentose, adaxial densely stipitate-glandular. Heads in corymbiform arrays. Involucres campanulate, 5–6 mm. Phyllaries in 5–6 series, tawny-silvery to silvery white (hyaline, shiny), ovate-lanceolate (not keeled or thickened along midribs, not apiculate), glabrous. Pistillate florets 200–250. Bisexual florets (13–)16–29. Cypselae not ridged, papillate-roughened. 2n = 28.
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