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©Copyright 1993 by the Regents of the University of California

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  • Up-to-date information about California vascular plants is available from the Jepson eFlora.

ASTERACEAE

SUNFLOWER FAMILY

David J. Keil, Family Editor and author, except as specified

Annual to tree
Leaves basal or cauline, alternate to whorled, simple to compound
Inflorescence: 1° inflorescence a head, each resembling a flower, 1–many, generally arrayed in cymes, generally subtended by ± calyx-like involucre; flowers 1–many per head
Flowers bisexual, unisexual, or sterile, ± small, of several types; calyx 0 or modified into pappus of bristles, scales, or awns, which is generally persistent in fruit; corolla radial or bilateral (rarely 0), lobes generally (0)4–5; stamens 4–5, anthers generally fused into cylinder around style, often appendaged at tips, bases, or both, filaments generally free, generally attached to corolla near throat; pistil 1, ovary inferior, 1-chambered, 1-seeded, style 1, branches 2, generally hair-tufted at tip, stigmas 2, generally on inside of style branches
Fruit: achene, cylindric to ovoid, generally deciduous with pappus attached
Genera in family: ± 1300 genera, 21,000 species (largest family of dicots): worldwide. Largest family in CA. Also see tribal key to CA genera: Strother 1997 Madroño 44(1):1–28. See glossary p. 25 for illustrations of general family characteristics.

CARDUUS

PLUMELESS THISTLE

David J. Keil and Charles E. Turner

Annual to perennial herb
Stems erect
Leaves alternate, reduced upward, decurrent as spiny wings, spiny-dentate and pinnately lobed, glabrous to tomentose; basal tapered to winged petiole; cauline sessile
Inflorescence: heads discoid, 1–20 at branch tips; involucre cylindric to spheric; phyllaries overlapping in several series, spine-tipped; receptacle flat, whitish bristly
Flowers: corollas white to pink or purple, tube long, slender, throat abrupt, short, lobes linear; anther bases short-sagittate, tips oblong; style with slightly swollen node, cylindrical above node, branches very short
Fruit ovoid, slightly compressed, glabrous; base slightly angled; pappus of many flat, minutely barbed, persistent bristles
Species in genus: ± 90 species: Eurasia, e Africa
Etymology: (Latin: ancient name)
Reference: [Howell 1959 Leaflets W Bot 9:17–29]

Introduced

C. nutans L.

MUSK THISTLE

Biennial
Stems 4–15 dm, glabrous to woolly, narrowly spiny-winged
Leaves: basal 10–40 cm, 1–2-pinnately lobed; cauline glabrous or sparsely hairy
Inflorescence: heads generally solitary, often nodding; involucre 2–7 cm diam, spheric; phyllaries spreading, lanceolate to ovate, spine-tipped
Flowers: corollas 20–25 mm, purple; tube 12–14 mm, throat 4–5 mm, lobes 4–6 mm
Fruit 4–5 mm, golden to brown; pappus 13–25 mm
Chromosomes: 2n=16
Ecology: Roadsides, pastures, waste areas
Elevation: 100–1200 m.
Bioregional distribution: Klamath Ranges, Cascade Range, n High Sierra Nevada, South Coast, Modoc Plateau, Mojave Desert
Distribution outside California: N.America.; native to Europe
Flowering time: Jun–Jul
Synonyms: var. leiophyllus (Petrovic) Arènes
Weedy.

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