Jepson Flora Project: Jepson Interchange    

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Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California

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



Annual to tree
Leaves simple to pinnately to palmately compound, generally alternate; stipules free to fused, persistent to deciduous
Inflorescence: cyme, raceme, panicle, or flowers solitary
Flower generally bisexual, radial; hypanthium free or fused to ovary, saucer- to funnel-shaped, often with bractlets alternate with sepals; sepals generally 5; petals generally 5, free; stamens (0)5–many, pistils (0)1–many, simple or compound; ovary superior to inferior, styles 1–5
Fruit: achene, follicle, drupe, pome, or blackberry- to raspberry-like
Seeds generally 1–5
Genera in family: 110 genera, ± 3000 species: worldwide, especially temp. Many cultivated for ornamental and fruit, especially Cotoneaster , Fragaria , Malus , Prunus , Pyracantha, Rosa , and Rubus
Reference: [Robertson 1974 J Arnold Arbor 55:303–332,344–401,611–662]
Family description, key to genera by Barbara Ertter and Dieter H. Wilken.


Barbara Ertter

Perennial to shrub, often bramble-forming, often prickly, prostrate or clambering to erect
Leaves generally palmately lobed to compound; leaflets often stalked, toothed
Inflorescence various
Flower: hypanthium shallow; bractlets 0; sepals 5, generally reflexed, tips generally linear; petals 5; stamens generally > 20; pistils few–many, ovaries superior, jointed to slender to club-shaped styles
Fruit: aggregate of sweet, fleshy-coated achenes (drupelets) that generally separate jointly from receptacle (raspberry-like) or separate jointly with part of fleshy receptacle (blackberry-like)
Species in genus: 200–700 species: worldwide, especially n temp, Andes
Etymology: (Latin: ancient name for bramble)
Coastal forms often have smaller, hairier, rounder leaves; hybrids and other escapes from cultivated expected.


R. pensilvanicus Poir.

Arched to erect brambles, ± nonglandular
Stem 5–10 mm diam, 5-angled; prickles many, ± wide-based, generally ± curved
Leaf compound; stipules linear; petiole ± 3–9 cm; leaflets 3–5, ± ovate-elliptic, sharply toothed, green below; longest leaflet stalk ± 10–30 mm; longest leaflet blade ± 6–12 cm
Inflorescence: raceme, generally 5–10-flowered; bracts often leaf-like
Flower: sepal tips 1–8 mm; petals 10–20 mm, obovate-round, white; pistils generally > 15
Fruit blackberry-like, ± oblong, black, glabrous
Ecology: Disturbed areas
Elevation: < 1500 m.
Bioregional distribution: California Floristic Province
Distribution outside California: native to e N.America
Synonyms: R. almus (L.H. Bailey) L.H. Bailey
Glandular R. allegheniensis Porter of e North America a scattered waif in CA.

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