Perennials, 20–50(–60) cm, strongly aromatic (rhizomatous, fibrous-rooted). Stems 3–20, erect, light brown, simple or branched, glabrous. Leaves cauline, dark green; blades lanceolate, 1.5–5 × 1–2.5 cm, 2-pinnatifid (primary lobes 5–9, 0.4–1.5 cm; cauline smaller, pinnatifid to entire), faces tomentose (abaxial) or glabrous (adaxial). Heads (peduncles 0 or to 3 mm) in usually paniculiform, sometimes racemiform, arrays 5–20 × 1.5–4 cm. Involucres campanulate to hemispheric, 2.5–3.5 × 2–4.5 mm. Phyllaries broadly ovate, glandular (at least at bases). Florets: pistillate 3–8; bisexual, sometimes functionally staminate, (15–)20–35; corollas bright yellow, 1.3–2.2 mm, glandular. Cypselae (light brown) ellipsoid (± arcuate, ribs 4, prominent), ca. 1 mm, glandular. 2n = 18.
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