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.



Robert Ornduff

Annual to tree
Leaves compound (palmate, pinnate, or leaflet 1), alternate, often ± basal in rosettes or in clusters at stem or rhizome tips, generally petioled; stipules generally 0; leaflets generally sessile
Inflorescence: cyme, sometimes umbel- or raceme-like, or flowers solitary, generally in axils; peduncle bracted
Flower generally bisexual, radial; sepals 5, free or fused at base; petals 5, free or fused above base; stamens 10 or 15, fused below, of 2 lengths; pistil 1, ovary superior, chambers 3–5, placentas axile, styles 1–5, generally ± free
Fruit: generally capsule, loculicidal
Seeds generally with aril
Genera in family: 8 genera, 575 species: especially temp. Often heterostylous.


Annual, perennial herb, shrub; roots fibrous or woody; bulbs, tubers, or rhizomes often present
Stem sometimes 0 or very short
Leaf petioled: stipules 0 or small; leaflets 3, generally ± obcordate in CA, generally entire, generally green
Flower: petals clawed; stamens 10; ovary chambers 5, styles 5, free, erect or curved
Fruit cylindric to spheric, explosively dehiscent
Seeds flat, often ridged; aril translucent
Species in genus: ± 480 species: especially temp
Etymology: (Greek: sour)
Reference: [Eiten 1963 Amer Midl Nat 69:257–309; Lourteig 1975 Phytologia 42:57–197]
Generally heterostylous; many (especially aliens in CA except O. laxa ) fine ornamental; some noxious weeds; contained oxalates may be toxic to livestock.


O. oregana Nutt.


Perennial; rhizome creeping, fleshy, scaly; bulbs 0
Stem 0 or very short
Leaves < 10, clustered at rhizome tips; petiole < 20 cm, hairy; leaflets < 4 cm, lower surface often purplish, upper often marbled
Inflorescence: flowers solitary; peduncle < 15 cm; bracts 2, near peduncle tip
Flower: sepals < 1 cm, lanceolate; petals < 2.5 cm, white to deep pink
Fruit < 12 mm, ± ovoid
Ecology: Moist conifer forests
Elevation: < 1000 m.
Bioregional distribution: North Coast, Outer North Coast Ranges, Central Coast, San Francisco Bay Area
Distribution outside California: to Washington
Fls spring to summer
Horticultural information: SHD: 17 &IRR: 4, 5, 6, 7, 8, 9, 14, 15, 16, 20, 21, 22, 23, 24; GRCVR, CVS.

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