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.



Reed C. Rollins, except as specified

Annual to subshrub
Leaves generally basal and cauline, alternate, generally simple; stipules 0
Inflorescence: generally raceme
Flower bisexual; sepals 4, free; petals (0)4, free, generally white or yellow, often clawed; stamens generally (2,4)6, generally 4 long, 2 short; ovary 1, superior, chambers generally 2, septum membranous, connecting 2 parietal placentas, style 1, stigma simple or 2-lobed
Fruit: generally capsule ("silique") with 2 deciduous valves, sometimes breaking transversely or indehiscent
Seeds 1–many per chamber
Genera in family: 300+ genera, 3000+ species: worldwide, especially cool regions; some cultivated for food (especially Brassica, Raphanus ) and ornamental
Recent taxonomic note: Recently treated to include Capparaceae [Rodman et al. 1993 Ann Missouri Bot Gard 80:686–699; Rollins 1993 Cruciferae of Continental North America. Stanford Univ Press]
Family description, key to genera by Robert A. Price.


Annual, biennial; hairs simple or 0
Stem generally erect, branched
Leaves petioled or sessile, variously lobed or dissected, green or glaucous
Inflorescence many-flowered; bracts 0
Flower: sepals erect to ± spreading; petals yellow, clawed
Fruit ascending to erect, linear to ± awl-shaped, generally cylindric, straight to ± curved, hairy or not; valves prominently veined; style conic or 0, stigma 2-lobed
Seeds many, generally 1 row per chamber; margin 0; not or ± gelatinous when wet; embryonic root at back of 1 cotyledon, sometimes obliquely so
Species in genus: ± 90 species: most continents
Etymology: (Greek: for various mustards)


S. irio L.


Stem 15–50 cm, branched from near base; hairs 0 or above, few, ± short, thin
Leaves: basal not clustered, petioled, pinnately lobed, terminal lobe > lateral, often hastate; upper cauline pinnately lobed to ± entire
Flower: petals 2.5–4 mm, barely > sepals, narrowly oblong, pale yellow, claws long
Fruit generally overtopping flowers, generally 3–4 cm, ± 1 mm wide; pedicel ascending, 5–11 mm, width < fruit width; style ± 0.5 mm
Seed < 1 mm, oblong, ± papillate; embryonic root obliquely at back of 1 cotyledon
Chromosomes: 2n=14
Ecology: Disturbed areas, orchards, roadsides
Elevation: < 800 m.
Bioregional distribution: Great Central Valley, Southwestern California, White and Inyo Mountains, Desert
Distribution outside California: to Texas, Baja California; native to Europe
Flowering time: Jan–Apr

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