Easter cassia (Senna pendula var. glabrata) in flower with its prolific, bright yellow blooms and pairs of opposite leaflets.
(Source: http://commons.wikimedia.org/wiki/File:Starr_070111-3261_Senna_pendula.jpg)

The showy, bright-yellow flowering Easter cassia (Senna pendula var. glabrata) can grow to around 5m in height and is dotted throughout the Dawn Road Reserve, particularly where there are sunny clearings or openings in the overhead canopy.

You have probably seen this eye-catching plant, alongside roads and waterways, or even in domestic gardens.

After it flowers densely in Autumn, the Easter cassia produces hundreds of slender green pods measuring up to 12cm in length. These are filled with very fertile, persistent seeds. When the pods mature they turn brown and their seeds are spread by birds, insects, water and gravity.

However, when it comes to identifying Easter cassia, an invasive weed species – especially when it’s not in flower – great care has to be taken not to confuse it with a beneficial native plant called the coffee bush (Breynia oblongifolia).

A Bushcare volunteer carefully positions a coffee bush (Breynia oblongifolia) where once Easter cassia (Senna pendula var. glabrata) plants were establishing along the embankment of a Dawn Road Reserve waterway.

The difference between the two is subtle but important, especially for Bushcare volunteers.

Easter cassia’s rounded leaflets are paired, opposite one another along the shrub’s stems, whereas the coffee bush’s very similar-looking leaves are alternate (offset) along its stems. When the coffee bush is flowering, it bears dull red fruit along its stems, between its leaves.

Notice the alternate leaves on the coffee bush (Breynia oblongifolia).

Notice the opposite leaves on Easter cassia (Senna pendula var. glabrata).

There is another dense, yellow-flowering tree you can see in some parts of the Dawn Road Reserve and it is called Dogwood (Jacksonia scoparia). Growing to around 4m in height, this drought-tolerant tree is a beneficial species. It has pea-shaped flowers in November and December and rather unusual branchlets which, when mature, have no leaves. While it produces prolific seed pods – unlike Easter cassia – its pods only contain one seed.

Keep your eyes out for this yellow-flowering shrub, Dogwood (Source: http://commons.wikimedia.org/wiki/File:Jacksonia_scoparia.JPG)

Sources:
Australian National Herbarium
Queensland Department of Agriculture and Fisheries 

———–

Images:
Trina McLellan, Wiki Commons