The following access keys are available throughout the Pittwater Council site. "m" will take you to the main content, "n" will take you to the site navigation, "s" will take you to the site search form and "t" will take you to the top of the page.

Main Content


Botanical name: Senna pendula
Noxious Weed Category: Class 4

Cassia   Cassia
Photos: Ku-ring-gai Council 


Also known as Senna and Arsenic Bush. Originating in South American, Cassia is a perennial sprawling multi-stemmed shrub or tree up to 5m tall. Stems and leaves are hairless.

Compound leaves divide into 3-5 opposite pairs of oval leaflets. Leaflets are dark green with a yellow coloured edge. Bright yellow flowers with 5 petals, clustering at branch ends. Flowers in autumn. Hard black seeds in bean-like pods, 5- 10 cm long, narrow and rounded. Ripening in winter.


The large seed pods are eaten by birds and other animals.

Impact on bushland

It replaces native vegetation and establishes in a wide range of native plant communities, including coastal heath and scrubland, hinddunes and riparian corridors.

Control Measure

The growth of the plant must be managed in a manner that continuously inhibits the ability of the plant to spread and the plant must not be sold, propagated or knowingly distributed.



  • Dispose of the large seed pods. 
  • Cassia is easily dug out, removing all roots. 
  • Cassia may also be treated using the cut and paint technique.

See Manual Weed Control Techniques.

Chemical: Please contact your local control authority for advice on chemical control.

Similar species

Cassia is often confused with a native shrub Breynia (Breynia oblongifolia) as their leaves are similar, but Cassia leaflets grow in opposite pairs, while Breynia leaves are alternate. See the Look-a-likes booklet

Updated: 18 Jul 2016