Cestrum parqui

Cestrum parqui, commonly known as green cestrum, green poison berry, Chilean cestrum or willow-leaved jessamine, and is sometimes incorrectly referred to as deadly nightshade, is a species of flowering plant in the family Solanaceae that is native to central and South America.

It is an upright, straggly, woody deciduous or semi-evergreen shrub 2–3 metres (6 ft 7 in–9 ft 10 in) tall with one or more brittle green stems. Light green leaves are alternate and shiny green to 12 cm (5 in) long, giving off a foul rubbery smell when crushed. It has sprays of small, fragrant, tubular yellow-green flowers approximately 2.5 cm long on the ends of the stems, flowering from late spring to autumn. These produce clusters of small, black egg shaped berries during summer to autumn.
Green cestrum is highly attractive to birds, and seedlings are often found growing under perching trees, along fence lines and on creek banks. It is also dispersed by water.
Spread by birds, it invades gardens, rural lands and bushland. It has a deep and persistent taproot. This weed is considered a major problem because of its toxicity to livestock (especially cattle) and poultry which eat green cestrum when there is a shortage of other feed. All parts of the plant material, stems, leaves, berries and even partly burnt roots pose a serious threat to livestock. Death is usually rapid and painful. The plant is also known to be toxic to other livestock and humans.

This species is defined as a noxious plant in New South Wales under the Noxious Weeds Act, 1993 and all plants must be destroyed.

In cultivation in the United Kingdom, this plant has gained the Royal Horticultural Society's Award of Garden Merit.