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Key to families | Table of families and genera
This text currently parallels The Jepson Manual: Vascular Plants of California, Second Edition that is now available at the University of California Press.
Text appearing in blue on this page will not appear in the printed book; it will be displayed only on the Web. 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, small tree, < 10 m.
Stem: branches alternate, stiff or flexible; twigs generally not thorn-tipped; winter bud scales present, generally ± 3 mm.
Leaf: scattered along branches or clustered on short- shoots, deciduous or evergreen; stipules generally deciduous; petioles generally glabrous; blade veins prominent or not.
Inflorescence: flowers 1 or in cyme-like clusters in axils.
Flower: unisexual ( bisexual), generally on separate plants, generally < 3 mm; hypanthium bell-shaped to cup-like, 2–3 mm wide; sepals 4–5, thin, spreading, not keeled adaxially; petals 0 or 4–5; disk thin, adhering to hypanthium; ovary appearing superior or partly inferior, chambers 2–4, each 1-ovuled, style 1, stigma 2–4-lobed.
Fruit: drupe, 2–3-stoned.
110 species: temperate, few tropics; some of value in medicine or as dyes. (Greek: name for plants of this genus) [Bolmgren & Oxelman 2004 Taxon 53:383–390] W.H. Brewer collected Rhamnus cathartica L., considered invasive in parts of US, in 1861, but it apparently never naturalized. Other taxa in TJM (1993) moved to Frangula.
Unabridged references: [Wolf 1938 Rancho Santa Ana Bot Gard Monogr 1]
1. Lvs deciduous; sepals 5; fruit black, 3-stoned ..... R. alnifolia
1' Lvs evergreen; sepals 4–5; fruit red, 2-stoned, or black, 3-stoned
2. Lf blade 20–60 mm, elliptic or ovate to lance-ovate; sepals 5; fruit black, 3-stoned — CCo (Monterey Co.), SCo (Newport Back Bay), expected elsewhere ..... [R. alaternus]
2' Lf blade 10–40 mm, elliptic to round; sepals 4; fruit red, 2-stoned (Rhamnus crocea complex)
3. Lf blade <= 15 mm, flat abaxially; branches spreading ..... R. crocea
3' Lf blade >= 15 mm, flat to concave abaxially; branches generally ascending
4. Lf blade elliptic; small tree; ChI ..... R. pirifolia
4' Lf blade elliptic to round; shrub; mainland
5. Lf blade glabrous or hairy abaxially, glabrous adaxially; twigs glabrous to finely hairy; CA-FP, DMtns ..... R. ilicifolia
5' Lf blade soft hairy; twigs densely hairy; s PR (San Diego Co.) ..... R. pilosa
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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