Lactuca praecox R.E.Fr.

Species

Angiosperms > Asterales > Asteraceae > Lactuca

Characteristics

Perennial herb, subscapose; root with creamy latex, root-crown with old leaf-bases, sometimes long-woolly; flowering stem(s) 1–several, erect, brown or purplish, 6–55 cm high, laxly branched or strongly contracted, glabrous or sparsely setose; proximal bracts sessile, narrowly triangular, to 4 cm long and 6 mm wide.. Leaves appearing after flowering, poorly known, in a rosette, lanceolate or ovate, 3–9 cm long, 1–4 cm wide, base cuneate, margins dentate and ciliate, apex acute, the purple midrib sparsely glandular-setose beneath.. Capitula precocious, many, in lax or contracted panicles 6–30 cm long; involucre cylindric or narrowly conical, 7–15 mm long; phyllaries brown or reddish green, ovate to lanceolate, 3–16 mm long, obtuse, glabrous except for a little hair-tuft at the very apex.. Florets 5–9 per capitulum; corolla yellow, tube cylindric, 2–3.5 mm long, pilose near the throat, ligules 10–14 mm long, 2.5–4.5 mm wide, distally papillose.. Achenes red-brown to dark brown, flattened ellipsoid, 6.5–9 mm long including a 1.5–3.5 mm long paler beak, 3-ribbed on each side, minutely puberulous; pappus white, 4–9 mm long.. Fig. 20/6 (achene).
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Leaves poorly known, appearing after flowering, radical, dark-brown lanate in the axils, up to c. 10 cm. long, linear-oblong and sessile, or elliptic to narrowly ovate and broadly cuneate to attenuate at the base, margins ciliate-denticulate with teeth up to c. 1.5 mm. long; petiole-like midribs up to 4 cm. long, persisting as polished golden-brown scales.
Flowering stalks 1-several ± diffusely branched, or much contracted and subpulviniform, glabrous or ± sparsely glandular-setose, bracteate; bracts foliaceous, sessile, up to c. 4 x 0.6 cm., very narrowly triangular, glabrous; branches mostly simple, up to c. 30 cm. long, divaricate-ascending, or much reduced, glabrous.
Achenes dark-brown to black, 8–9 mm. including a 2.5–3.5 mm. long paler beak, 1.5–1.75 mm. wide, narrowly ellipsoid, swollen-ribbed on the margins with 1 or sometimes 2–3 smaller ribs between, minutely antrorsely hispidulous; pappus several-seriate, copious, of fine white barbellate setae, c. 5 mm. long.
Florets c. 5 per capitulum; corollas yellow, 12–16 mm. long, tube narrowly cylindric, ± densely pilose near the throat; ligules 10–14 x 3–4.5 mm., oblanceolate, ± pilose below, lobes papillose above.
Phyllaries glabrous, guttulate, green sometimes purple-tinged, ciliolate above, the outer from c. 3 mm. long and narrowly ovate, the inner to c. 16 mm. long and lanceolate.
Involucre 7–10 x 2.5 mm. at time of flowering, increasing to c. 17 x 3.5 mm. in fruiting capitula, cylindric to narrowly conical, later narrowly campanulate.
Capitula precocious, numerous, sessile or stalked, solitary or in clusters of 2–4; stalks up to c. 5 cm. long, glabrous.
An erect subscapose perennial herb 7–55 cm. tall, from a narrowly turbinate rootstock.
Life form perennial
Growth form herb
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Sexuality hermaphrodite
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Mature height (meter) 0.07 - 0.55
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Environment

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Hardiness (USDA) 9-12

Usage

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Edible -
Therapeutic use -
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Cultivation

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Distribution

Lactuca praecox world distribution map, present in Malawi, Tanzania, United Republic of, and Zambia

Identifiers

LSID urn:lsid:ipni.org:names:228182-1
WFO ID wfo-0000019988
COL ID 8VCQD
BDTFX ID -
INPN ID -
Wikipedia (EN)
Wikipedia (FR)

Synonyms

Lactuca praecox