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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.
Shrub, tree. stipule spines generally 2 per node; roots long, spreading. Leaf: even-2-pinnate, alternate, deciduous; 1° leaflets generally 2–4, opposite; 2° leaflets generally many, opposite. Inflorescence: axillary, head or spike-like raceme, many-flowered. Flower: radial, small, green-white or yellow; calyx shallowly bell-shaped, lobes short; petals generally inconspicuous; stamens 10, exserted, free; style exserted, generally appearing before stamens. Fruit: indehiscent, ± flat, ± narrowed between seeds or tightly coiled, pulpy when young, then woody. Seed: several.
± 44 species: especially America (also southwestern Asia, northern Africa). (Greek: burdock, for obscure reasons) Cult, naturalized worldwide.
Unabridged references: [Burkhart 1976 J Arnold Arbor 57:220–524; Holland 1987 Madroño 34: 324–333]
1. Fruit tightly coiled; petals fused
2. Inflorescence spike-like raceme, 4–8 cm; leaf hairy ..... P. pubescens
2' Inflorescence head to spike-like raceme, < 4 cm; leaf glabrous or short-hairy ..... [P. strombulifera]
1' Fruit not coiled; petals free
3. Plant ± glabrous; 2° leaflets (10)15–25 mm, length 7–9 × width ..... P. glandulosa var. torreyana
3' Plant with short, dense hairs; 2° leaflets 4–15 mm, length 3–4 × width ..... P. velutina
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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