Plants 10–150 cm . Stems erect to ascending, pale green when young, becoming whitish, fastigiately branched, glabrous, resinous at and distal to nodes. Leaves usually ascending, recurved when older; blades filiform (adaxially sulcate), 15–35 × 0.5–2 mm, midnerves obscure, apices acute, often mucronate, faces glabrous, gland-dotted (in pits and sessile); axillary leaf fascicles often present. Heads in rounded, cymiform arrays (to 5 cm wide). Peduncles usually less than 10 mm (ebracteate). Involucres turbinate, 6–10 × 2–4 mm. Phyllaries 15–20 in 3–4 series, green to tan, ovate to lanceolate, 1.5–6 × 0.7–1.5 mm, unequal, outer herbaceous or herbaceous-tipped, inner mostly chartaceous (bodies truncate or tapering gradually or abruptly to bases of herbaceous appendages), midnerves faint (margins membranous, usually ciliate), apices (outer and mid) cuspidate (tips squarrose), abaxial faces glabrous, resinous. Ray florets 0. Disc florets 5–7; corollas 4.7–7 mm. Cypselae tan, narrowly turbinate to subcylindric or narrowly ellipsoid, 4–5 mm (5-ribbed), moderately hairy to sericeous, often gland-dotted (glands spheric, glistening) distally; pappi whitish, 4.5–5.5 mm. 2n = 18.
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