Home
About Us
Weeds
Weed Alerts
Declared Noxious Weeds
Herbs
Trees
Grasses
Shrubs
African boxthorn
Bitou Bush
Blackberry
Boneseed
Cape or Montpelier Broom
Gorse or furze
Green Cestrum
Groundsel bush
Harrisia Cactus
Karoo thorn
Kochia other than Summer or Mock Cypress
Koster's curse
Lantana
Mysore thorn
Prickly Pear other than Indian Fig
Scotch or English Broom
Siam Weed
Spanish broom
Sweet briar or briar rose
Tropical soda apple
Vines
Aquatic
Noxious Weeds Act
Plans and Strategies
News
Links
Weed Resources
Contact
 

Green Cestrum

Green cestrum flowers

Green cestrum bark

Green cestrum fruits

Green cestrum plant

Red cestrum

Yellow cestrum flowers

   



family

Solanaceae

status

Green cestrum (Cestrum parqui) is declared noxious in Bega Valley, Bombala, Eurobodalla, Goulburn-Mulwaree, Palerang, Queanbeyan, Shoalhaven, Southern Slopes, Upper Lachlan and Wingecarribee LCAs in class 3.

Description

A straggly evergreen shrub 2-4m high with arching stems. The bark has prominent raised pale dots (lenticels) which are obvious on young stems. Leaves are alternately arranged on the stems, dark green and slightly shiny above and paler below, with slightly wavy margins and a pointed tip, 7-14cm long. The prominent central vein on each leaf is yellow and strongly raised on the underside, particularly near the leaf base. The leaves have a very unpleasant smell when crushed, although it is possible to find the odd specimen without this characteristic. Flowers are tubular, about 2cm long, with the petals flared at the tip. They are yellow-green in colour and occur in dense elongated clusters at the branch tips. Fruits are succulent, about 1cm across, and round or oval. They ripen from green to black.

PREFERRED HABITAT AND IMPACTS

More common in the north of the region, but occasionally found as far south as the Bega Valley. Found in dry and wet eucalypt forest and rainforest, where it can dominate the understorey and prevent regeneration by native plants. The plant is poisonous to both livestock and humans. Handling cestrum may cause contact dermatitis in some people.

Dispersal

Birds, dumping of plants carrying seed.

Look-alikes

The foliage of cestrum is not particularly distinctive and could probably be confused with some native shrubs of wet eucalypt forests and rainforest, but if the flowers are present the plant should be recognisable. The strong unpleasant smell of the crushed leaves is unmistakeable, but the occasional plant can be found which does not have this smell.
The flowers of green cestrum are sweetly scented at night. A related and very similar species, lady-of-the-night (Cestrum nocturnum ) is promoted as a garden plant for its strongly perfumed flowers, and the two plants could easily be confused. Lady-of-the-night has larger leaves (10-15cm by 4-7cm wide compared with 2-7cm by1-3cm in green cestrum) and white rather than purple berries. It has not been found to naturalise as readily as green cestrum, but being a bird-spread species should be avoided in the garden.
Two other Cestrum species are also occasionally naturalised in the northern part of the region, from garden plantings. They are red cestrum (Cestrum elegans) which has red flowers and berries, and orange cestrum (Cestrum aurantiacum) which has orange-yellow flowers and white berries. They should not be planted in the garden.

Control

Seedlings may be hand pulled or dug out. Cut and paint or stem inject mature plants, preferably before they begin to develop seed. To improve the effectiveness when using the cut and paint method, peel the bark back all around the stump and apply herbicide quickly to both the cut face and the exposed outer wood. Spray with selective herbicides. Follow-up treatment will be needed on seedlings.