Scientific name: Cestrum parqui L’Hērit.

Common names: Green cestrum, green poisonberry

Family: Solanaceae

Origin:

Native of South America.

Habit:

Erect, perennial shrub usually growing 1-2 m tall, but occasionally reaching 5 m in height. It tends to form clumps as it produces suckers.

Habitat:

A common weed of urban and rural areas. It thrives along watercourses and is also found in many parks and gardens.

General description:

Stems and leaves

Young shoots are often hairy and green in colour. Newer stems are whitish, while older stems become woody with striated bark at the base. Leaves are alternately arranged with leaf stalks (petioles) 3-12 mm long. Leaf blades are oval or elongated (2-10.5 × 0.5-2.4 cm in size), with a pointed tip and tapering at the base.

Flowers and fruit

The flowers are borne in clusters at the end of the branches. They have greenish yellow petals fused into a  tube (1.2-1.7 cm long) with triangular lobes (3-5 mm long) at the tip. The flowers that are borne near the base of the inflorescence may have thin bracts underlying them. Flowering occurs all year round, but is particularly abundant in spring. The fruit are ovoid berries (1-1.5 cm long) that are glossy black when ripe. Each contains numerous prism-shaped seeds.

Distinguishing characteristics:

Shrub with alternately arranged leaves with a distinctive unpleasant odour. Roots are yellow and woody and the flowers are yellow-green, tubular, and very elongated.

Noxious status:

This species is declared noxious in Queensland, Victoria, New South Wales and Western Australia. It is toxic to stock.

Sources:

Anonymous. (2000). Noxious Weed List for Australian States and Territories. National Weeds Strategy Executive Committee, Launceston.

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.

Stanley, T.E. and Ross, E.M. (1983-1989). Flora of South-eastern Queensland. Volume 2. Department of Primary Industries, Brisbane.