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Key to families | Table of families and genera

Specimen numbers are hyperlinked to records in the Consortium of California Herbaria data view where possible. Taxa are hyperlinked to entries in the Jepson Interchange via the "[Online Interchange]" link.

 

ARCTIUM BURDOCK
Biennial. Stem: 1–several, branched distally. Leaf: basal and cauline, alternate, long-petioled, widely ovate; base deeply cordate; margin entire or toothed; gradually reduced distally on stem. Inflorescence: heads discoid, in leafy-bracted clusters; involucre ± spheric; phyllaries graduated in many series, ± linear, bases appressed, tips stiffly radiating, hooked-spiny; receptacle ± flat, epaleate, bristly. Flower: many; corolla pink to ± purple, lobes narrowly triangular; anther base tailed, tips ovate, acute to obtuse; style branched just above distal hairy ring, branches oblong, obtuse. Fruit: ± compressed, rough or ribbed, glabrous, attachment basal; pappus several series of rough bristles, readily deciduous.
10 species: Eurasia, northern Africa. (Greek: bear) [Keil 2006 FNANM 19:168–171]
Unabridged references: [Duistermaat 1996 Gorteria Suppl. 3:1–143]

Key to Arctium

1. Heads generally 25–40 mm diam, generally long-peduncled in ± rounded or flat-topped clusters; inner phyllaries generally green, margins minutely hairy; pappus 2–6 mm ..... A. lappa

1' Heads generally 10–25 mm diam, sessile to short-peduncled in raceme- or panicle-like clusters; inner phyllaries generally purple-tinged, margins minutely serrate; pappus ± 2 mm ..... A. minus

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Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
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