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, generally ± glandular, generally resinous-smelling; caudex generally branched
Stem generally ascending to erect
Leaves generally basal, odd-1-pinnate, generally ± flat; cauline alternate, reduced upward; uppermost lateral leaflets generally ± fused with terminal
Inflorescence: cyme, open or of dense clusters; pedicels generally straight
Flower: hypanthium a ± flat-bottomed cup, width ± 2 X length; bractlets 5, generally 2/3 sepals; sepals 5, often reflexed; petals 5, generally ± = sepals, blunt, white; stamens 10, filaments flat, often forming a tube; pistils 2–many, ovaries superior, styles jointed below fruit tip, ± thicker at base
Fruit: achene
Species in genus: 19 species: w North America
Etymology: (J. Horkel, German plant physiologist, 1769–1846)
Data apply to basal leaves, pressed hypanthia.


H. bolanderi A. Gray


Plant ± matted, grayish
Stem 10–30 cm; hairs ascending to appressed
Leaf 3–8 cm; leaflets ± 7 per side, generally ± crowded, 4–10 mm, wedge-shaped to obovate, ± 5-toothed ± 1/3 to base, densely hairy
Inflorescence ± dense to open, several–many-flowered; pedicels generally 2–4 mm
Flower: hypanthium width 2–4 mm, > 2 X length, inner wall ± hairy; bractlets 0.5–1 mm wide, ± elliptic; sepals ± 3–4 mm; petals 3–5.5 mm, oblong to oblanceolate; filaments 0.5–2 mm, bases 0.3–0.4 mm wide, anthers ± 0.5 mm; pistils generally 10–20, styles 1–2 mm
Fruit ± 1.2 mm
Ecology: UNCOMMON. Edges of vernally wet places in pine forest
Elevation: 450–1100 m.
Bioregional distribution: Inner North Coast Ranges (Colusa, Lake, Mendocino? cos.)
Horticultural information: IRR, DRN: 1, 7, 14, 15, 16, 19, 20, 21, 22, 23, 24 &SUN: 4, 5, 6, 17; GRCVR.
See the CNPS Inventory for information about endangerment and rarity.
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