American Wintercress :

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)
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)

At Edgewood

Specific References