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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. congesta Hook. subsp. nemorosa D.D. Keck


Plant tufted or rosetted, ± grayish green, ± odorless; caudex 0–few-branched
Stem 15–30 cm, densely glandular above
Leaf 4–8 cm; leaflets 2–5 per side, separated, 5–12 mm, ± elliptic, < 5-toothed < 1/4 to base, very hairy
Inflorescence: clusters 1–several, head-like, generally 5–15-flowered; pedicels generally ± 2 mm
Flower: hypanthium width generally 3–4.5 mm, < or = 2 X length; bractlets < 0.5 mm wide, linear; sepals 2–4.5 mm; petals 2.5–4 mm, generally widely obovate; filaments 0.5–2 mm, bases 0.2–0.5 mm wide, anthers ± 0.5 mm; pistils ± 10, styles 2–3 mm
Fruit ± 2 mm
Ecology: Vernally moist, rocky clay, generally serpentine
Elevation: 300–800 m.
Bioregional distribution: nw Klamath Ranges (Del Norte Co.)
Distribution outside California: sw Oregon
See the CNPS Inventory for information about endangerment and rarity.
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