Sonchus wilmsii R.E.Fr.

Compositae, G. V. Pope. Flora Zambesiaca 6:1. 1992

Morphology General Habit

An erect perennial herb, up to c. 1 m. tall.

Morphology Stem

Stems simple, somewhat woody below, ± dilated hollow and stout above, glabrous sometimes glaucous, leafy throughout.

Morphology Leaves

Leaves sessile, 5–15 x 2.5–6(8) cm., oblanceolate to panduriform in outline, lanceolate-ovate and smaller towards the stem apex, the basal few leaves smaller and evanescent; cauline leaves variable, runcinate-dentate throughout, or remotely and narrowly-lobed pinnatisect throughout, acute mucronate at the apex, semi-amplexicaul or auriculate-sagittate below, denticulate to sharply and irregularly dentate on the margins, glabrous sometimes glaucous.

Morphology Reproductive morphology Inflorescences Capitulum

Capitula 2–7 in a much reduced corymbiform-cymose arrangement, or somewhat aggregated with stalked capitula subtended by subsessile immature capitula, or sometimes the capitula solitary on long branches.

Morphology Reproductive morphology Inflorescences Bracts Involucre

Involucres c. 20 x 12 mm. in fruiting capitula, cylindric-campanulate to spreading, ± persistently white-lanate below.

Morphology Reproductive morphology Inflorescences Bracts Phyllaries

Phyllaries imbricate, increasing from c. 4 mm. long on the outside to c. 20 x 2 mm. on the inside; the outermost narrowly ovate, becoming subcoriaceous with a thickened midrib, the basal portion eventually swollen; the inner phyllaries narrower, lanceolate-lorate, membranous, puberulous or glabrescent.

Morphology Reproductive morphology Flowers Florets

Florets numerous.

Morphology Reproductive morphology Flowers Corolla

Corollas yellow, c. 18 mm. long, pubescent about the junction of the tube and ligule; ligule often becoming pinkish outside, 4–5 mm. long, oblong.

Morphology Reproductive morphology Fruits

Achenes pale-brown, c. 4.5 mm. long, narrowly ellipsoid, slightly flattened, glabrous, ribbed; marginal and middle ribs well developed with c. 2 secondary ribs between, the main ribs becoming swollen and rugulose; pappus white copious, 12–14 mm. long, composed of minute barbellate setae and fine down-like hairs.