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Cassia
Environmental Weed
Botanical name: Senna pendula
Photos: Ku-ring-gai Council
Description
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.
Dispersal
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
Manual:
- 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