The power of partnership in McLaren Vale is demonstrating how feral olive trees can be punted from our roadsides for good.
Feral European olive trees are a major pest plant that spread and displace native species and damage habitat for native wildlife, as well as being a significant bushfire hazard because they’re rich in oil.
But Biodiversity McLaren Vale (BMV), the City of Onkaparinga and SA Power Networks (SAPN) are fighting back, joining forces to not just clear the pests from rural roadsides but replace them with native species so the olives don’t come back.
Branson Road (just east of Pethick Road) is ground zero for a new demonstration site. More than 80 BMV volunteers, council staff and elected members came together last Sunday 4 August, planting more than 570 metres of southern roadside with around 1,200 native seedlings provided by BMV.
The planting day was the culmination of years of work from the council and SAPN to remove hedge-like feral olive trees that lined the 1.1-kilometre length of Branson Road, plus several hundred metres along Pethick Road adjacent to the Maslin Creek Reed Swamp crossing.
The City of Onkaparinga has employed cutting-edge spatial-mapping technology over the past 15 years to chart woody weed infestations and prioritise their removal to improve biodiversity outcomes, improve sight lines for drivers and reduce bushfire risk.
Information is shared with Biodiversity McLaren Vale to help it remove feral vegetation from creek lines and replace this with native plant species for the betterment of the region’s native flora and fauna, vineyards, farms and community.
SA Power Networks is also on board with roadside feral olive removals because of its desire to keep powerlines clear of vegetation.
These shared goals were realised at last Sunday’s planting site, with the native species planted chosen to increase the biodiversity value of the local area and while reaching mature heights lower than the powerlines.
The efforts mean four ‘spans’ (the distance from one Stobie pole to the next) of roadside beneath power lines on Branson Road have now been revegetated – a fitting way to mark 100 years of the Stobie pole.
Jock Conlon, City of Onkaparinga Coordinator of Natural Areas Conservation, says the project demonstrates what can be achieved when everyone comes together to do their part.
“The removal of these feral olives and the subsequent planting day is a win-win-win,” he says.
“It’s really pleasing to see a community engaged in removing feral olive trees from private property, joining forces with a council to revegetate roadsides under SAPN powerlines with more appropriate species.
“There’s still a lot of work to do across Onkaparinga, but the Branson Road site is an example of how we could tackle infestations in other parts of our city.
"We are currently controlling and removing olive trees along the Coast to Vines Trail between McLaren Vale and Willunga and planting local native tree species. Feral olive trees, be warned!”
Biodiversity McLaren Vale chair and co-founder Geoff Hayter said Branson Road, between Pethick and Gilbert Roads, was “almost hedge-like” eight years ago.
“The feral olives are now all gone thanks to the council’s Free the Tree initiative and SAPN’s under-powerline clearance, along with advocacy and roadside management assistance from Lot 50-Kanyanyapilla,” he said.
“A great job by all concerned. Long may it last. Now, to ice the cake, we’ve planted out some of the cleared roadside to celebrate what’s been achieved and to demonstrate to the rest of the world what can be done.
“We’re planning and planting for a feral olive-free Willunga Basin.”
PHOTO: Planting roadside natives at the August field day
Photo courtesy of Biodiversity McLaren Vale