Jepson Flora Project: Jepson Interchange    

link to manual TREATMENT FROM THE JEPSON MANUAL (1993) previous taxon | next taxon
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.


Perennial, glabrous
Stem generally simple, < 2 m, ± coarse
Leaves simple, entire to pinnately lobed, sometimes dissected underwater
Flower: sepal bases not sac-like; petals short-clawed, white; filaments wider toward base
Fruit: septum generally incomplete; stigma bilobed
Seeds 2 rows per chamber; wing 0; embryonic root at edges of both cotyledons
Species in genus: 4 species: 3 Eurasia, 1 North America
Etymology: (Latin: horseradish)


A. rusticana P. Gaertn., B. Mey. & Scherb.


Perennial, generally erect; roots deep, swollen, spongy
Stem often branched, 6–10(20) dm
Leaves: basal long-petioled, 3–5 dm, widely ovate to ovate-oblong, crenate to ± toothed; cauline petioled or not, lowest like basal, middle and upper often lobed
Flower: petals 5–7 mm
Fruit ± round, ± flat perpendicular to septum, generally abortive; style ± 0.3 mm, stigma prominent, persistent
Seeds 4–6 per chamber, generally abortive
Chromosomes: 2n=32
Ecology: Ditches, roadsides, moist places
Elevation: < 200 m.
Bioregional distribution: Central Coast, Great Central Valley, San Francisco Bay Area, expected elsewhere
Distribution outside California: temperate N.America; native to Eurasia

previous taxon | next taxon
bioregional map for ARMORACIA%20rusticana being generated

Retrieve Jepson Interchange Index to Plant Names entry for Armoracia rusticana
Retrieve dichotomous key for Armoracia
Overlay Consortium of California Herbaria specimen data by county on this map
Show other taxa with the same California distribution | Read about bioregions | Get lists of plants in a bioregion
Return to the Jepson Interchange main page
Return to treatment index page

University & Jepson Herbaria Home Page |
General Information | University Herbarium | Jepson Herbarium |
Visiting the Herbaria | On-line Resources | Research |
Education | Related Sites
Copyright © by the Regents of the University of California