Shrubs, 100–400 cm (much branched, broomlike). Stems erect, striate, sharply angled, green distally, glabrous, resinous. Leaves cauline (proximal withered and/or sparse at flowering); sessile; blades (1-nerved) linear-lanceolate, 5–15 × 1–2 mm, reduced to scales distally, thick, bases narrowed, margins entire (often revolute), apices acute, faces glabrous, minutely gland-dotted, resinous . Heads borne singly (on nearly leafless branches) or (laterally on branchlets) in dense paniculiform arrays. Involucres cylindric to hemispheric; staminate 4–5.2 mm, pistillate 3–8 mm. Phyllaries ovate to lanceolate, 1–5 mm, margins yellowish, slightly scarious, medians green to yellow, apices rounded to acute (greenish, abaxial faces glabrous, resinous). Staminate florets 18–35; corollas 4.2–5 mm. Pistillate florets 19–31; corollas 2.5–3.5 mm. Cypselae 2–2.6 mm, finely 8–10-nerved, glabrous; pappi 7–12 mm. 2n = 18.
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