Cardinia Reservoir giant pine scale removal


Melbourne Water is committed to preserving and protecting our water catchments and the local environment in your area. We are removing the infestation of ‘giant pine scale’ from Cardinia Reservoir and replanting the affected areas with native plants. These works will protect the local environment from further damage from giant pine scale and ensure the long-term biodiversity of the area.

What is giant pine scale?

Giant pine scale is a tiny scale insect that feeds on the sap of pine, fir and spruce trees and spreads by crawling to nearby host trees. Trees infested with giant pine scale display a white wax secretion resembling cotton wool on the trunks and branches. Infested trees will typically dry up and die as a result of the insects feeding on the tree’s sap. Giant pine scale is notoriously very difficult to manage – the insects have no known predators in Australia and there are no effective chemical treatment options available.

Giant pine scale at Cardinia Reservoir

Giant pine scale was confirmed in Melbourne for the first time in 2014, and first detected in Cardinia Reservoir in 2017 in approximately 20 trees. Our efforts to contain this spread have had limited impact, with the estimated number of infested trees at more than 500, covering approximately 14 hectares. We anticipate all of these infested trees would die in the next 5 to 10 years.

There are 15,000 to 20,000 pine trees growing in the Cardinia Reservoir catchment. Removing the trees infested with giant pine scale and those at risk is necessary to prevent the broader risk of infestation across the region. Dying trees are also a safety hazard as they increase the available fuel in the event of a bushfire, as well as having the potential to fall on land managers working in the catchment.

Giant pine scale insect, image courtesy of David Smith, ArborCarbon
Giant pine scale insect

Cardinia Reservoir pine infested with giant pine scale
Cardinia Reservoir pine tree infested with giant pine scale. Images courtesy of David Smith, ArborCarbon








Safe tree removal and catchment replanting

Melbourne Water has worked closely with experts including the Department of Environment, Energy and Climate Action (DEECA) to build a Biosecurity Plan for safe treatment and removal of the pine trees. The highest standard of equipment hygiene is being used to avoid spreading giant pine scale further within the catchment or surrounding area.

To ensure the long-term biodiversity of Cardinia Reservoir, the affected areas will be revegetated and replanted with more than 33,000 native trees and plants, commencing in Autumn 2024.

Minimal local impact

There is unlikely to be any direct local impact to people outside the closed catchment during these works. There may be some increased vehicle movement around the catchment and possible noise from machinery operating on site.

Visitors to the area and particularly to Cardinia Reservoir Park will see some areas in the closed catchment where the works are occurring. These areas where the pines are being removed will look bare for a while until the native replanted trees can develop.

By managing this infestation of giant pine scale, we continue to protect our important catchment forests and supply the community with a safe and reliable water supply, now and for generations to come.

Map of giant pine scale in Cardinia Reservoir

June 2023

Works commenced to remove the infestation of giant pine scale

Not Started

Autumn 2024

Revegetation and replanting of the affected areas commences with more than 33,000 native trees and plants

More information on giant pine scale

Agriculture Victoria website - Giant pine scale | Priority pest insects and mites | Pest insects and mites | Biosecurity | Agriculture Victoria

Watch the video Giant pine scale management in Victoria (

Contact us

Melbourne Water via 131 722 or [email protected]

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