Volunteer co-ordinator Richard Pettinger said an infestation of wilding rowan or mountain ash (Sorbus spp) trees had appeared in the upper reaches of McQuilkans Creek, high on the northwest side of Flagstaff.
It is thought a specimen tree was planted in the garden of a TB sanatorium about 100 years ago on the Flagstaff-Whare Creek Rd.
A large number were now established on that road, and birds brought the seeds up the hill from there.
The species found in this area were very invasive and threatened native forest and grassland on land on the hill, he said.
Dunedin City Council’s Three Waters Dept, the Flagstaff Scenic Reserve and the Otago Tramping and Mountaineering Club (OTMC) own the land where the wilding trees were now found. The OTMC-owned land is a property known as Ben Rudd’s.
Passers-by spotted the obvious red berries that mature rowans produce in autumn and alerted the OTMC and the trust that manages Ben Rudd’s land to the emerging problem.
The trust has been making significant improvements to the amenity, landscape and biodiversity values of the OTMC’s land, with assistance from individuals and organisations including the DCC and Otago Regional Council’s biodiversity funds, Trees That Count, Dunedin Amenities Society, QEII National Trust, and most recently the Cleveland Charitable Foundation, Mr Pettinger said.
A group of volunteers will gather from 9am this Saturday to control the invasive pest plants as the rowans begin to show spring growth. The volunteers include members of OTMC, (Orokonui) Halo Project, QEII, Forest and Bird and Richard Forbes Gardening.
A herbicide benign enough to be used in a tributary that runs in several kilometres to part of Dunedin’s water supply catchment will be carefully applied to cut stems.
The DCC Three Waters team purchased the herbicide and gave permission for this urgent work to be carried out.
"We feel like a winning team, doing something important and positive."
Anyone from Dunedin was welcome to join. Contact Richard Pettinger on 027 950-4517.
Staff Reporter
