Department of Primary Industries, Parks, Water and Environment, Hobart, 2011
Scientific name: Barbarea australis Hook.f., Fl. Nov.-Zel. 1: 14 (1852)
Common Name: native wintercress (Wapstra et al. 2005)
Group: vascular plant, dicotyledon, family Brassicaceae
Status: Threatened Species Protection Act 1995: endangered
Environment Protection and Biodiversity Conservation Act 1999: Critically Endangered
Distribution: Endemic status: Endemic to Tasmania
Tasmanian NRM Region: Cradle Coast, North, South
Description and taxonomy
Barbarea australis is an annual or short-lived perennial in the Brassicaceae family (Curtis & Morris 1975, Hewson 1982). It is an erect plant up to 50 to 100 cm high. The lower stem leaves are 8 to 10 cm long and form a basal rosette or radiating cluster. They are stalked, broader at the ends and develop 2 to 3 small lateral lobes on the leaf stalk below the main part of the leaf. The leaves on the upper stem are simple with wavy margins. The flowers are yellow with 2 to 8 mm long petals and the many seed capsules or pods are 20 to 40 mm long and 2 to 2.5 mm wide. The seeds are broad and oval, 1.5 mm long and have irregular edges or narrow wings.
Three species of Barbarea occur in Tasmania (Buchanan 2009), two of them being introductions from the northern hemisphere (Barbarea intermedia and Barbarea verna). The introduced Barbarea species can be distinguished from Barbarea australis by their deeply-divided upper stem leaves and by seeds that lack a defined edge and that are relatively rounded.
The Brassicaceae family has its greatest concentration of species in the temperate regions of the Northern Hemisphere (Hewson 1982). In Australia, the Brassicaceae are represented by 375 genera. There are two species of Barbarea endemic to Australia, Barbarea australis and Barbarea grayi, the latter being an alpine species in Victoria and New South Wales.
The Brassicaceae family is represented in Tasmanian by sixty-eight taxa (Buchanan 2009). Twenty-one of these are considered to be native to Tasmania, including two endemics (Barbarea australis and Cheesemania radicata). The Brassicaceae is a family with a relatively high concentration of rare and threatened plant species in Tasmania, with seven species listed on schedules of the TSP Act in 2009.