
American Rocket, American Yellowrocket
Barbarea orthoceras
NATIVE
Description (Jepson, PlantID.net)
- Eudicotyledon
- Eudicots are a major lineage of flowering plants; see family for general characteristics
- Mustard Family (Brassicaceae)
- Perennial herb
- Stems are erect, with ridges
- Leaves
- Form a basal rosette and occur along the stem, reducing upward
- Each leaf is divided into 1-4 leaflet pairs (pinnately compound), with a larger terminal leaflet
- Leaflets may be wavy edged and sparsely toothed
- Stem (cauline) leaves attach directly to the stem (sessile)
- Form a basal rosette and occur along the stem, reducing upward
- Flowers
- Inflorescence (flower arrangement) is a raceme (unbranched stem with stalked flowers opening from the bottom up)
- Each flower with 4 yellow petals forming a cross
- 6 stamens (male flower parts), 4 long and 2 short
- Sepals (outer flower parts) yellow to yellow green
- Ovary superior (above the attachment of other flower parts)
- Fruit is an upright silique (long, narrow pod) with a horn-shaped tip
- Height to 20 in.

Distribution
- Native to California
- Grows predominately in moist areas
- See Calflora for statewide observations of this plant
- Outside California, grows in Western North America, and in parts of central and eastern Asia
- Grows at elevations to 11,000 ft.
Uses (San Mateo County Parks prohibits removal of any natural material)
- Wildlife
- Visited by flies, bees, and beetles
- Larval food source (host) for several butterfly species, e.g. Sara orangetip (Anthocharis sara) and checkered white (Pontia protodice)
- Human
- Leaves can be eaten raw or cooked
Name Derivation
- Barbarea (bar-BARE-ee-a) – named after St. Barbara, a 3rd-century Greek Christian martyr
- orthoceras (or-tho-SER-as) – from the Greek órthios, “straight, upright” and kéras, “horn,” referring to the horn-tipped fruit
- Wintercress – common name for plants in this genus
- Cress is a name associated with cruciferous plants (Mustard family)
- Rocket – common name for many plants in the Mustard family
- From the Italian ruchetta or rucola, a diminutive of the Latin eruca, once a name for a kind of mustard plant and now a genus in the Mustard family, which includes the leafy vegetable arugula or rocket (Eruca vesicaria)
Notes
- Crushed plant tissue of most Mustard species release peppery-smelling, pungent-tasting isothiocyanates (cyanide compounds), derived from glucosinolates (Ishida 2014); see Mustard family for more details
ID Tips
- May be confused at Edgewood with 2 yellow-flowering, non-native mustards — short-podded mustard (Hirschfeldia incana) and hedge mustard (Sisymbrium officinale)
American Wintercress | Hedge Mustard | Short-podded Mustard | |
Growth Habit | perennial herb | annual herb | perennial herb |
Height | ≤ 20 in. | ≤ 24 in. | ≤ 31 in. |
Hairy Stem | no | sometimes | yes |
Basal Leaf Terminal Lobe | broad-rounded tip | acutely-pointed tip | broad-rounded tip |
Flower Stalk | erect, compact | laterally sprawling | laterally sprawling |
Fruit | not appressed to stem | appressed to stem | appressed to stem |
Habitat | woodland | disturbed areas | disturbed areas |
At Edgewood
- Found in woodlands
- See iNaturalist for observations of this plant
- Flowers March – July
Specific References
Ishida, M., et al. 2014. Glucosinolate metabolism, functionality and breeding for the improvement of Brassicaceae vegetables. Breeding science, 64: 48–59. J-STAGE.