Have you been for a walk up to the Point lately? Yes? How brilliant is the display of vibrant yellow flowers all over the northern side of the headland. Wow!
At this time of year those flowers light up the coastal reserve like wattles light up a dull winter woodland. And no, it’s not a wattle. And no, it’s not a native either. It’s called winter senna and it comes from South America. Bitou Bush and Singapore Daisy are also in flower and – ‘dang it’ – they’re all weeds.
Winter senna is also known as cassia, climbing cassia or the less than enticing moniker, arsenic bush. Birds and insects however love the abundant flower display despite Winter senna being one of our more intrusive weed species.
Those bright yellow flowers can be seen throughout the year but are prolific through March and April, hence its other common name, Easter senna. The plants produce a fruit that is actually a 10-20 cm long bean pod containing 20-40 seeds. Birds and other animals spread the seed and those that aren’t eaten drop to the ground and readily germinate so it spreads very quickly and easily.
Winter senna is a garden escapee and is regarded as an environmental weed in NSW and Qld. It’s found in warmer coastal districts in disturbed forests and along roadsides. It’s very important not to dump your garden waste in coastal reserves as this is another way senna and other weed species invade our bushland. Please use your green recycling bin for any cuttings or seedpods from senna or other garden plants. Council will compost it all for us.
Winter senna is a very hardy plant and will re-shoot from any root-stock left in the ground after removal or pruning so don’t be surprised if your hard work is rewarded by a flush of new growth. And a word of caution; winter senna and its cousin smooth senna can be easily confused with a similar native species, Senna acclinis (Brush or Rainforest senna).
Rainforest senna looks almost the same as the winter senna but it’s an Aussie native, and is endemic. It’s also host to a number of yellow butterfly species but is classified as rare and threatened in our area so please be careful before you remove any senna from your gardens.
Check out the differences below:
Winter senna (bad) 3-8 pair of rounded leaflets, round seedpods, flowers March to April.
Smooth senna (bad) 3-6 pair of pointy leaflets, round seedpods, flowers in spring and autumn.
Rainforest senna (good) up to 7 pairs of rounded leaflets, flat seed pods, flowers throughout summer.
Landcare Dates for May:
Times are 8.30 to 10.30 am
Wed 1st Lower Lennox Point – surfer’s car park
Wed 8th Boulder Beach – Coast Rd car park
Wed 15th Seven Mile Dunes – opp William St
Wed 22nd Boulder Beach – Coast Rd car park
Wed 29th Lower Lennox Point – surfer’s car park
For further info, visitlennoxheadlandcare.org
email firstname.lastname@example.org, phone Shaun on
0448 221 210 or find us on Facebook ‘Lennox Head Landcare’.