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©Copyright 1993 by the Regents of the University of California
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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.



Willard W. Payne

Annual to shrub, monoecious
Leaves often opposite below, generally alternate above, generally petioled, hairy, glandular
Inflorescence: staminate heads generally many in ± spikes or racemes, phyllaries fused into shallow cup; pistillate heads generally clustered below staminate, generally spiny, bur-like; involucre ± 0; receptacle chaffy; chaff scales spirally arrayed, fused below, tips generally becoming spiny; each pistillate flower in separate chamber
Staminate flowers ± many; corolla yellow or translucent; anthers free; style unbranched
Pistillate flowers 1–5; corolla 0; style branches long
Fruit enclosed in bur; pappus 0
Etymology: (Greek: early name for aromatic plants; the mythic food of the gods)
[Payne 1976 Plant Syst Evol 125:169–178] Closely related to (indistinct from) Hymenoclea [Miao et al. 1995 Amer J Bot 82:924–932; Baldwin et al. 1996 Madroño 43:15–27] Wind-blown pollen often highly allergenic.


A. confertiflora DC.

Perennial 3–18 dm, from rhizome-like roots
Stems green to brown, bristly, ± puberulent
Leaves: petioles with lobed wings; blade < 16 cm, ± ovate, 2–4-pinnate
Inflorescence: staminate heads 3–9 mm diam, involucre lobes 5–9, green above; pistillate heads 1(2)-flowered
Fruit: bur 2–5 mm, 1.5–5 mm diam, ovoid, base ± tapered; spines few (sometimes vestigial), scattered, short, cylindric, hooked, pitted at base on upper surface
Chromosomes: 2n=72,108
Ecology: Disturbed areas
Elevation: < 350 m.
Bioregional distribution: Sierra Nevada Foothills, San Joaquin Valley, San Francisco Bay Area, South Coast
Distribution outside California: to c US, n Mexico
Synonyms: Franseria c. (DC.) Rydb
Often forms large colonies.

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