.jpg)
Manual of the New Zealand Flora.
26. Sonchus, Tourn
26. Sonchus, Tourn.
Erect leafy annual or perennial succulent herbs, juice milky. Leaves alternate or radical, entire or toothed or pinnatifid; cauline often amplexicaul. Heads peduncled, in terminal irregularly branched corymbs or panicles, homogamous. Involucre ovoid, usually becoming conical after flowering; bracts imbricated in several series, the outer smaller. Receptacle flat, naked. Florets all ligulate. Anthers shortly tailed at the base. Achenes ovoid or ellipsoid, more or less compressed, ribbed and often transversely rugose, not beaked. Pappus-hairs copious, in many series, soft, white, simple. Species from 24 to 28, mostly natives of the temperate regions of the Northern Hemisphere; a few spread over the whole world, but probably naturalised in many districts. One of the New Zealand species is endemic, the two others are cosmopolitan.
* Annual.
| Upper leaves amplexicaul, with rounded auricles. Achenes longitudinally ribbed, not transversely wrinkled | 1. S. asper. |
| Upper leaves amplexicaul, with acute auricles. Achenes longitudinally ribbed and transversely wrinkled | 2. S. oleraceus. |
** Perennial.
| Leaves large, 1–2½ ft. long. Heads 1–1½ in. diam., purplish; pedicels cottony | 3. S. grandifolius. |
| 1. | S. asper, Hill, Herb. Brit. i. 47.—A tall succulent annual herb 2–3 ft. high, with a hollow grooved stem, glabrous or sparsely glandular above. Leaves lanceolate, entire or toothed or pinnatifid; page 388margins waved or crisped, spinous-toothed; lower ones petiolate, upper semi-amplexicaul with rounded auricles. Heads ¾–1 in. diam., crowded in a short; corymbose panicle, sometimes almost umbellate. Involucre glabrous, bracts acute. Achenes oblong, compressed, longitudinally ribbed but not marked with transverse wrinkles or asperities.—Kirk, Students' Fl. 362. S. oleraceus var.β, Hook. f. Fl. Nov. Zel. i. 153; Handb. N.Z. Fl. 166.
Var. littoralis, Kirk in Trans. N.Z. Inst. xxvi. (1894) 265.—Often biennial or perennial. Stems rather stout, 1–2 ft. high, sparingly branched; root thick and fleshy. Leaves mostly radical, spreading, 3–7 in. long, linear-oblong or linear-obovate, obtuse or acute, finely or coarsely toothed, rather thick, almost fleshy; cauline leaves few, acute, amplexicaul. Outer involucral bracts obtuse, inner acute. Achenes longitudinally ribbed, glabrous.—Students' Fl 362. North and South Islands, Stewart Island, Chatham Islands: Abundant throughout, from the North Cape southwards; the variety littoralis confined to maritime cliffs. Sow-thistle; Rauroroa; Tawheke; Puwha. Flowers from spring to autumn. As this was collected by Banks and Solander it must be regarded as indigenous. The variety littoralis is a very curious form, and may be entitled to rank as a species. |
| 2. | S. oleraceus, Linn. Sp. Plant. 794.—A tall erect annual herb 2–3 ft. high, glabrous or sparsely glandular above. Leaves lanceolate, entire or toothed or pinnatifid; margins flat or nearly so, not crisped; lower ones petiolate, upper semi-amplexicaul with sagittate acute auricles. Heads ¾–1 in. diam., crowded in a short corymbose panicle, often subumbellate. Involucres glabrous or slightly cottony at the base, sometimes with a few glandular hairs. Achenes linear-oblong, compressed, longitudinally grooved and conspicuously transversely wrinkled.—S. oleraceus var. a, Hook, f. Fl. Nov. Zel. i. 153; Handb. N.Z. Fl. 166; Kirk, Students' Fl. 362.
Kermadec Islands, North and South Islands, Stewart Island, Chatham Islands: Abundant throughout. Sow-thistle; Pororua; Rauriki. Flowers from spring to autumn. Perhaps not truly native. |
| 3. | S. grandifolius, T. Kirk in Trans. N.Z, Inst. xxvi. (1894) 266.—Rootstock stout, fleshy, creeping, sometimes 2½ in. diam. Stem tall, robust, succulent, corymbosely branched above, 2–5 ft. high. Radical leaves 1–2½ ft. long, 4–8 in. broad; petioles 6–9 in., stout, dilated at the base but not amplexicaul; blade oblong or ovate-oblong, irregularly pinnatifid or pinnate; segments 4–6 pairs, broad, overlapping, coarsely doubly serrate or dentate, almost spinous-toothed, subcoriaceous, scabrid above, veins finely reticulate. Upper cauline leaves sessile by a broad base. Heads large, 1–1½ in. diam.; pedicels clothed with white cottony wool. Involucral bracts in 3–4 series, broadest at the base, gradually tapering into page 389blunt points, the outer with a row of short spines down the median line. Florets numerous, purplish. Achenes large, broad, spongy, with 3–6 longitudinal ribs; margins broad.—Students' Fl. 362.
Chatham Islands: Enys! Cox! January–February. A very handsome and distinct species, endemic in the Chatham Islands. |