Stopping the spread of the highly invasive coral cactus is one of the priorities in a Rangelands NRM project currently rolling out on Tarmoola Station near Leonora in the WA goldfield region.
The project, funded by Rangelands NRM through the Australian Government’s Caring for Our Country program, is being delivered by the Goldfields Nullarbor Rangelands Biosecurity Association (GNRBA) working with St Barbara Mining, the current lessee of the Tarmoola pastoral lease.
Rangelands NRM Program Manager – Southern Rangelands Jane Bradley said the coral cactus () infestation started quite innocently with a few plants down at the Tarmoola station tip.
“Over the past 10 years, the core infestation has spread to approximately three hectares, with isolated clumps and individuals spread across an area of 66 square kilometres,” Ms Bradley said.
The coral cacti’s ability to shed segments and reproduce rapidly has ensured its rapid spread at Tarmoola. Infestations of the same species of cacti can also be found at Mertondale, to the north east of Leonora.
Ross Wood from the GNRBA developed the idea of fencing out the core infestation to prevent further spread by stock.
“Although currently destocked, Tarmoola regularly has visits from cattle from neighbouring stations, with animals walking straight through the core infestation on their way to a watering point to the east of the homestead,” Ms Bradley said.
St Barbara’s Steve Charley, PhoebeSampson and Daniel Gibbons have also previously been involved in trialling different herbicides on the coral cactus in an attempt to determine the best herbicide option for killing the invasive species.
“The project will ensure the core infestation is fenced out, thus prevent further spread by cattle, kangaroos and other vectors, with outlier populations mapped and treated,” Ms Bradley said.
As part of the project, a cactus forum was recently held in Leonora 27-28 May 2013. Twenty-one people from local agencies, industry, pastoralists, local government and NRM attended to hear Helmuth Zimmerman from South Africa talk about the history and role of biological controls for cactus, and the opportunities that a coming up for their use in Western Australia. Henry Rutherford, Weeds of National Significance (WoNS) Co-ordinator also attended the meeting and presented information from the Cactus Forum.
Ms Bradley said there is a cochineal insect currently in quarantine that has been proven to work effectively on coral cactus.
“Rangelands NRM, GNRBA and St Barbara are keen to see the biological control released in the core infestation at Tarcoola,” she said.
Image: Brett Lewis, Mac Jensen and Ross Wood inspecting the coral cactus at Tarmoola: (© J Bradley)