Common Australian Garden Weeds

Coronopus didymus

Scientific name: Coronopus didymus (L.) Smith


Photo of the habit of bittercress (coronopus didymus) with inconspicuous green coloured flowers and small fruits.


Dissected leaves and greenish flowers of bittercress.


Young bittercress plant with highly divided leaves arranged in a basal rosette.


Very young seedling of bittercress.

Synonyms: Lepidium didymus L.; Senebiera didyma (L.) Pers.

Common names: Bittercress, lesser swine-cress, lesser wart-cress

Family: Brassicaceae

Origin:

Native of Europe.

Habit:

Annual or biennial herb, much branched and forming a slender taproot. First growing into a rosette, later growing prostrate or semi-erect stems to 30 cm.

Habitat:

Common weed of cultivation (especially cereal crops), disturbed areas and gardens.

General description:

Stems and leaves

Stems are usually hairy, prostrate or semi-erect and much-branched. Basal leaves are highly divided (pinnatasect) up to 8 cm long and have petioles. As leaves are produced further up the stem they tend to have shorter petioles and more entire margins stem leaves are alternate. Has an unpleasant odour.

Flowers and fruit

Flowers are small and greenish with four 1-2 mm long sepals, petals may be absent, if present there are four of them, 0.5 mm long and white. They are borne in racemes at the ends of short branches. Fruits have two globular green warty lobes that separate easily into 1-seeded articles. Flowering occurs mainly in winter.

Distinguishing characteristics:

Highly divided leaves forming a fairly prostrate rosette. Unpleasant odour and greenish flowers. Small, green, and globular 2-lobed fruit.

Noxious status:

Not noxious.

Sources:

Kleinschmidt, H.E., Holland, A. and Simpson, P. (1996). Suburban Weeds. 3rd Edition. Department of Primary Industries, Brisbane.

Parsons, W.T. and Cuthbertson, E.G. (1992). Noxious Weeds of Australia. Inkata Press, Melbourne.

Friend, E. (1983). Queensland Weed Seeds. Department of Primary Industries, Brisbane.

Anonymous. (1994). Queensland Vacsular Plants: Names and Distribution. Queensland Herbarium, Brisbane.