Cassia

(Also known as Senna)

Senna pendula var. glabrata

Family: Fabaceae

Type of weed:

Flowering Months: , ,

Description

A multi-stemmed shrub that grows up to about 5 m tall.

Leaves grow in alternate formation, and are pinnate with 3–6 pairs of leaflets.

Bright yellow flowers, 30 mm across with 5 petals, in leafy clusters at the tips of the branches, appear in autumn.

Hard, black, irregular seeds are found in slender pods that are green, maturing to brown. There are around 5–40 seeds per pod.

Don’t confuse with…

Can be confused with native Breynia (Breynia oblongifolia); however the native plant has alternate leaves. Some Phyllota species also look similar.

Dispersal

The seed pods are eaten by birds and other animals.

Impact on bushland

Cassia smothers and replaces native vegetation and establishes monocultures in a wide range of native plant communities and disturbed areas including riparian corridors.

Distribution

. Mostly in mid and lower Mountains.

Alternative planting

Native plants

Local species of:

  • Phyllota spp.
  • Gompholobium spp.
  • Lambertia formosa
  • Hakea teretifolia
  • Banksia spinulosa

Council provides a tool, on its Mountain Landscapes website, to help you choose native alternative plantings. Choose your village, soil, vegetation community and the purpose of your planting, and the tool will give you suggestions.

There are native nurseries in several Blue Mountains villages, including Glenbrook, Lawson and Katoomba. Please also ask at your favourite local nursery.

Control

Because the berries are spread by birds, treat plants before they fruit.  Bag the large seed pods and if possible dispose of in a hot compost to kill the seeds. Other cut parts of the plant can be spread out to dry off the ground. Once dead, the material will decompose in place, or can be composted.

For more info

For key points on these techniques: