Cakile maritima (sea rocket) is a succulent, annual herb to 0.5m. The petals are 8-14mm, purple, pink or white. The fruit is a silicula 12-27mm long, divided into an upper and a lower segment. It is common on beaches from Shark Bay to Esperance. Native of Europe and Africa. C. edentula (American sea rocket) is similar to the previous species in habitat, stature and flower colour. It differs in its smaller petals, 4.5-8mm long, less deeply lobed leaves and the shape of the fruit (see diagram). Only recorded to date from the extreme south-east of the State, near Eucla. Native of North America.
Cakile
maritima
, RR
Capsella bursa-pastoris (shepherd's purse) is an erect herb, growing up to about 40cm under fertile conditions. The flowers are white, with petals 2-3mm long. It can be recognised by the distinctive shape of its fruits, siliculas, roughly triangular in outline, but depressed at the top. A native of Europe, this species is found occasionally in lawns, gardens, market gardens and disturbed sites around Perth and in the south-west. Flowers from June to November.
Capsella
bursa-pastoris
, PH
Cardamine sp. (hairy bittercress, common bittercress, flickweed). The separation of species in this genus is difficult and taxonomic revision is needed. In the past, most plants have been loosely identified as C. hirsuta, although most are almost hairless, except at the very base. They are slender annual herbs, up to 30cm tall (though often much shorter), with pinnate leaves in which the terminal leaflet is the largest. The petals are white, about 3mm long. The fruit is a narrow siliqua up to 2.5cm long, that bursts open at the slightest touch when ripe, sometimes flicking the seeds further than 50cm. Commonly found in well watered sites, such as plant nurseries and gardens in Perth and the south-west. A native of Europe.
Cardamine
hirsuta, SE
Cardaria draba (hoary cress) DP is an upright perennial to 40cm spreading from rhizomes, with stem-clasping leaves and heads of small white flowers. It is an occasional weed of cropping areas in the southern wheatbelt, subject to eradication efforts. Native to the Mediterranean.
Cardaria
draba
, CG
Carrichtera annua (Ward's weed) is an annual herb up to 40cm, covered in bristly hairs. The leaves are very finely divided. The petals are about 8mm long, yellow with purple veins. The fruit is a silicula, 6-7mm long, at least half of which is a characteristic spoon-shaped beak. A native of the Mediterranean, this weed is now abundant in the Goldfields and Nullarbor shrublands, often dominating mine rehabilitation sites, from Laverton to Eucla.
Carrichtera
annua
, RR
Coronopus didymus (lesser swinecress) is a prostrate annual with pinnate leaves, smelling strongly when crushed. The whitish petals are either very short and hidden by the sepals, or absent. The rounded fruits are siliculas, 1.5mm long and 2-3mm wide, compressed at right angles to a narrow septum. A common weed of disturbed sites, gardens, lawns and islands, from Meekatharra south. Its origin is uncertain, possibly South America.
Coronopus
didymus
, GK
Diplotaxis species in Western Australia are difficult to distinguish, however, the following two species have been recorded. D. muralis (wall rocket) is an annual or biennial, upright or often spreading, up to 50cm high. The leaves, that have a more lobed appearance than Brassica species, smell strongly when crushed. This, and the following species, can be distinguished from other yellow-flowered crucifers with siliquas by having two rows of seeds on each side of the septum. The petals are 4-9mm long and the fruits mostly 2-4cm long, with a beak of about 2mm. It flowers January to August and is an occasional weed of verges and wasteland from Shark Bay to Hopetoun. Native to central and southern Europe. D. tenuifolia (Lincoln weed, sand rocket) is a more erect perennial than D. muralis, to 1.3m. The petals are larger, 8-12mm long, and also yellow. The fruits are 2-6cm long. It is found in wasteland in a few places near Perth and Bunbury. Native to Europe.
Diplotaxis
tenuifolia, RR
Heliophila pusilla A slender, spring-flowering annual, up to 0.5m with white petals 2-3mm long. The fruit (siliquas) are up to 2cm long, flattened and constricted around the seeds. It is found in dunes, banksia woodlands and shrublands, in coastal areas from Perth to Albany. Native of South Africa.
Heliophila
pusilla
, RR
