Giant pine scale, or GPS, has been detected in Adelaide’s north-eastern suburbs following ongoing surveillance of an area where infected trees were removed in the Highbury Aqueduct Reserve and Hope Valley Reservoir Reserve last year. These sap-sucking pests have the potential to impact the state’s $1.4 billion forest industry. Source: Timberbiz
The Department of Primary Industries and Regions is currently working with the Department for Environment and Water, SA Water, the South Australian forest industry and the City of Tea Tree Gully in managing this latest outbreak.
Trees are being removed in the Highbury and Hope Valley areas, in order to protect both local street trees, surrounding urban forests and the South Australian forestry sector.
Any wildlife found to be present, including protected animals and the eggs of protected animals, is being managed appropriately in accordance with relevant legislation.
A spokesperson for the State Government said that they understood the loss of mature trees would have an impact on the Highbury community, and that the decision to undertake tree removal had not been made lightly.
“Given the risk giant pine scale poses, it is important that all steps are taken to eliminate this pest insect,” the spokesperson said.
“To protect street trees and the parks and gardens within the Highbury and Hope Valley areas, as well as South Australia’s $1.4 billion forest industry, there is an urgent need to contain the pest insect through the removal of affected and surrounding trees.
“Other eradication options have been trialled in the area in an effort to reduce the impact of tree removal, however they have not been successful in full eradication of giant pine scale. As a result, the removal of trees remains the best-known option for eliminating the pest.
“Previous giant pine scale detections at Dernancourt and North Adelaide in 2014 and Highbury in 2018 were successfully controlled through using this same approach and we are confident that the removal of these final known GPS-infected trees in SA will be again successful in mitigating this pest.”
With human activity a known key driver of giant pine scale spread, particularly through the pest sticking onto shoes, clothing or equipment, a restricted area has been established around the infestation site, including the closure of the Aqueduct Trail.
Visitors to Highbury Aqueduct Reserve are advised not to enter the restricted area or remove any wood material from the reserves.
Once the tree removals are complete the restricted area will remain in place for up to three months to ensure that there are no live giant pine scale remaining onsite prior to re-opening for public access.
The tree removal site will be remediated including revegetating with local native species of trees, shrubs and grasses when seasonal conditions are optimal for planting.
Native to the eastern Mediterranean region, giant pine scale (Marchalina hellenica) causes branch dieback, gradual desiccation and tree death. It feeds exclusively on plants from the pine family, such as introduced pines, firs and spruces.
“With surveillance so critical to this stage of the response, all agencies involved are calling on the public, particularly local residents, to report anything that looks suspicious,” the spokesperson said.
Giant pine scale can be detected by looking for masses of the characteristic white cotton-like secretions on the trunks and branches of pine trees.
If you see or suspect giant pine scale, report it to the Exotic Plant Pest Hotline on 1800 084 881. Further information on the pest is also available at www.pir.sa.gov.au/giant-pine-scale
For enquiries regarding the management of giant pine scale at Highbury Aqueduct Reserve, email [email protected]
For enquiries regarding the management of giant pine scale at Hope Valley Reservoir Reserve, contact SA Water on 1300 SA WATER (1300 729 283).
