Weeds creeping in on headlands
RECENT wet seasons have seen an unprecedented growth of introduced weeds on Coast headlands, threatening the native grasses and herbs which grow there.
Coffs Coast national park manager Glen Storrie said introduced pasture and lawn species such as paspalum and kikuyu were invading the natural kangaroo grass sward on headlands such as Woolgoolga, Look at Me Now and Sapphire.
“We have a control program in place, through contractors such as EnVite, to spray and remove the kikuyu as far as the mown strip along headland roads such as Woolgoolga, which council maintains,” he said.
“We will also be discussing with council a mowing regime which would favour the natural kangaroo grass over the kikuyu.”
As anyone with a lawn knows, kikuyu requires frequent regular mowing, especially after wet weather when it grows especially vigorously, out-competing the more sedate kangaroo grass.
Kangaroo grass requires much less mowing, perhaps never, and varieties have been developed for suburban lawns which require very little maintenance and are also drought-free.
The problem is, regular fortnightly mowing by the council on road verges on the headlands ends up encouraging the kikuyu at the expense of the natural kangaroo grass and flowering herb sward, which consists of at least 19 different native species.
This has the effect of steadily increasing the area that needs to be mowed and eventually the native vegetation will disappear and constant maintenance will be required.
Mr Storrie said the native sward on Muttonbird Island was different.
“Muttonbird Island is not a headland, it is the same as the Solitary Islands and the difference is the muttonbirds,” he said.
“Muttonbirds need islands to breed on. They won’t normally breed on the headlands, and this results in a different mix of species.
“The weed problem on Muttonbird Island is also different, and at this time of year is dominated by farmer’s friend, which is going to seed.”
Alex Groot, of Woolgoola Back Beach Dunecare, said the kikuyu followed the new paved path installed a few years ago and had spread halfway to the beach.
“People using the path spread the seeds,” Mr Groot said.
“As well, the bobcat work, like any disturbance, allows the introduced pasture plants to establish before the native grasses can come back.
“Dunecare is particularly concerned about bitou bush growing on Flat Top.”