Scientific Name
Cestrum parqui L'Her.
Common Names
green cestrum, green poison berry
Origin
Central and South America
Family
Solanaceae
Distinguishing Characteristics
This can be a large woody shrub. Its new shoots and leaf axis may have some hairs. Mostly this plant is hairless. Small leaves/leaflets may also be found at the leaf axis. When crushed this plant has a strong, distinctive and somewhat unpleasant smell.
Leaves are alternate, narrow and lance shaped, 2-7 cm long, usually 1-3 cm wide; the leaf stem (petiole) can be up to 1 cm long. Leaves are a grey/green colour and are a paler shade underneath.
Inflorescences (groups of flowers) are formed at the end of the stems. Flowers are funnel-shaped, either sessile (have no stalk) or on pedicels (on the stalk) and greenish yellow in colour. Flowers can be found on this plant throughout the year.
Fruit is egg-shaped, to about 10-15 mm in length and is a black berry when ripe.
This plant is very difficult to kill. It usually responds best to herbicide (such as Roundup) when it is applied at 100% strength, to long scrapes along the stem. To scrape the stem: take a knife and drag it up and down the stem revealing the white inner layer. Depending on plant size, scapes could be 10cm - 30cm in length. Herbicide should be applied to the wound within 10 seconds.
Other plants easily confused with this plant
This plant is very distinctive, especially when a leaf is crushed and smelt.
Sources & References
"Weeds - an illustrated botanical guide to weeds of Australia" by B. A. Auld and R. W. Medd
"Plantnet FloraOnline" (2005) http://plantnet.rbgsyd.nsw.gov.au/
South Coast Weeds www.esc.nsw.gov.au/weeds
Prepared by Justin KY Chu, July 2005
Checked by IEWF, January 2006
Checked by Barbara Wiecek, Botanic Gardens Trust, Sydney, June 2006