Senecio biserratus

Detailed description

Annual to short-lived subsucculent perennial herb up to 1 m tall but usually much less. Stems erect, basally sparsely or sometimes moderately coarse-hairy; indumentum reducing upwards. Mid-stem leaves more or less evenly spaced and sized, 50–150 mm long, width:length ratio 1.5–4, dark green to yellow green, elliptic to narrow-elliptic or lanceolate, coarse-dentate to deeply lobate; segments 3–9 per side extending along much of length, tending to be larger in proximal ⅔, antrorse, deltoid to near oblong; base usually auriculate, with auricles divided, semiamplexicaul; margin serrulate or denticulate, with denticulations frequent; both surfaces glabrous or sparsely hispid to scabridulous, rarely coarse-hairy; lower surface pale green to purple, more or less glabrous except on veins. Uppermost leaves similar, width:length ratio 1-2, sometimes widest at auricles. Unit inflorescences of many capitula; total number of capitula per stem often 50–200; not overtopping or only moderate; mature lateral peduncles mostly 5–10 mm long. Calycular bracteoles 3–6, 1.0–2.0 mm long; peduncle and margin of bracteoles more or less glabrous at anthesis; involucre 4.5–7.5 × 1.0–1.5 mm; involucral bracts predominantly 7–10, glabrous, apex erect; stereomes of dry material flat to slightly convex, thin, green, minutely purpled at apex. Florets 12–20, pale yellow, c. 70% female; corolla-lobes nearly oblong, thickened apically; corolla of bisexual florets 4.5–6.0 mm long, 4–5-lobed; corolla-lobes of female florets 3–4, 0.2–0.3 mm long. Cypsela 2.0–3.2 mm long, dark brown, narrow oblong to oblong-ellipsoid, with papillose hairs in dense bands, width:length ratio of hairs 1–3. Pappus 5–6 mm long.