E-Flora BC: Electronic Atlas of the Flora of British Columbia

Barbarea orthoceras Ledeb.
American winter cress (American yellowrocket)
Brassicaceae (Mustard family)

Introduction to Vascular Plants

© Rosemary Taylor  Email the photographer   (Photo ID #38441)

E-Flora BC Static Map
Distribution of Barbarea orthoceras
Click here to view our interactive map and legend
Details about map content are available here
Click on the map dots to view record details.

Species Information

Click on the image below to view an expanded illustration for this species.

Biennial (occasionally perennial) from a taproot and a simple stem-base; stems stiff, erect, angled, branched, (10) 20-60 cm tall.
Basal leaves pinnately lobed, long-stalked, less than 12 cm long, with 1-5 pairs of lateral lobes, terminal lobe largest, egg-shaped and entire or irregularly toothed; stalks and sometimes leaflets long-fringed or sparsely short-hairy; lowermost stem leaves with 2-10 pairs of lateral lobes, upper pinnately cleft with the terminal lobe the largest, often clasping the stems.
In single and terminal racemes or more often in compound, reduced racemes in lower leaf axils; flower stalks not stout, less than 1 mm thick, 2-3 mm long; petals pale yellow, broadly spoon-shaped, 3-5 mm long; sepals pale yellow-green, about 2 mm long.
Erect to spreading-ascending siliques, (1.5) 2.5-5 cm long, straight; styles 0.5-1.5 mm long, not beaklike; seeds in 1 row, finely pitted, about 1.5 mm long.

Source: The Illustrated Flora of British Columbia

Habitat / Range

Moist streambanks, meadows and forests in the lowland, steppe and montane zones; common along the coast, less frequent elsewhere in BC; N to AK, YT and NT, E to NF, and S to MN, NH, CO, AZ and CA.

Source: The Illustrated Flora of British Columbia


Ecological Framework for Barbarea orthoceras

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class




Elevation (metres) 61 587 1044
Slope Gradient (%) 0 12 100
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
171 195 240
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
5 6 7
Modal Nutrient Regime
Number of field plots
 species was recorded in:
Modal BEC Zone Class
All BEC Zones (# of stations/zone) species was recorded in: BG(1), BWBS(2), CDF(1), CWH(1), PP(1), SBS(1), SWB(1)


The climate type for this species, as reported in the: "British Columbia plant species codes and selected attributes. Version 6 Database" (Meidinger et al. 2008), is not evaluated, unknown or variable.

Synonyms and Alternate Names

Barbarea americana Rydb.
Barbarea orthoceras var. dolichocarpa Fernald

Taxonomic and Nomenclatural Links

Additional Photo Sources

General References