Giant Pine Scale

The Hon. J.M.A. LENSINK (15:08): I seek leave to make a brief explanation before asking the Minister for Primary Industries a question regarding the management, or lack thereof, of giant pine scale outbreaks.

Leave granted.

The Hon. J.M.A. LENSINK: In 2023, giant pine scale was detected at the Hope Valley Reservoir Reserve resulting in the loss of approximately 120 trees. Despite assurances that containment efforts were underway, subsequent detections occurred at Silverlake Reserve and the Highbury Aqueduct Reserve leading to the felling of hundreds of additional trees.

The minister has previously advised that a multilevel agency working group was established in response to the outbreak. However, the advice that the Liberal opposition has received is that confusion persists in the community regarding which agency is responsible for leading the efforts to manage the infestation and what proactive surveillance measures were in place prior to these outbreaks.

Residents have also expressed concerns regarding the lack of a coordinated recovery plan to restore the environmental damage caused by the large-scale loss of mature trees. My questions for the minister are:

1. What are the immediate containment actions that were taken following the initial detection to specifically prevent spread into other parts, including into Highbury?

2. Is it her agency or, if not her agency, which agency is responsible for the coordination of management of outbreaks in public reserves?

3. What outcomes have been achieved by the giant pine scale working group so far?

4. What surveillance activities were undertaken by PIRSA or associated agencies prior to the detection at Silverlake Reserve? I note the trees have now been felled next to the kindergarten.

5. Will the government commit to funding, replanting and environmental restoration for all areas affected by giant pine scale outbreaks in this vicinity?

6. At what other sites has the pest been detected and what is the plan to address these issues?

The Hon. C.M. SCRIVEN (Minister for Primary Industries and Regional Development, Minister for Forest Industries) (15:11): I thank the honourable member for her question. Giant pine scale is native to the Eastern Mediterranean region and causes branch dieback, gradual desiccation and tree death. It does feed exclusively on plants from the pine family, such as pines, furs and spruces. Giant pine scale presents a threat to softwood forestry and wood processing industries in South Australia, with the sector directly and indirectly producing more than $1.46 billion of economic activity annually.

Giant pine scale was first detected in Victoria and South Australia back in 2014. At that time it was affecting what we call amenity trees, so not commercial plantations but amenity trees in streets, parks and gardens. In 2017, it was determined nationally that it was not possible to eradicate giant pine scale from Australia, in part because it is a difficult pest to detect in the early stages of infestation because it does manifest in the tops of trees and because chemical control treatments were shown to be ineffective at that time. I remember that, prior to that 2017 decision, when I was working in the forest industry, it was of course a big part of discussions across the nation because it obviously has a significant impact on softwood trees of the pine variety, and clearly an eradication would have been beneficial but was not considered to be possible.

At that time a one-year transition to management program was enacted to assist industry to manage giant pine scale in Australia broadly. Due to that now endemic status of giant pine scale in Australia, management of the pest rests with land managers, landowners and industry where it is in a commercial plantation. In South Australia, people are obliged to report infestations to PIRSA, as doing so allows affected stakeholders to assess new detections and to act.

In Victoria, there is an active containment program underway. Here in South Australia, we are aiming to eliminate all known detections of the pest. However, I would note that, where trees are in private gardens, for example, there is no legislated way that we can force the removal of those trees. In 2023, detections were made in pine trees within SA Water's Hope Valley Reservoir Reserve, which was an area not accessible to the public. It was also in nearby Elliston Reserve and in the Highbury Aqueduct Reserve. Tree removals for all detection sites, I am advised, are now complete.

The interagency GPS response team was formed following that 2023 detection. Members include representatives from PIRSA, from SA Water, ForestrySA, City of Tea Tree Gully, Australian Forest Products Association, University of South Australia, National Parks and Wildlife Service SA, and an independent expert from ArborCarbon. PIRSA's role in the response included: providing technical support; convening response team meetings; responding to some public queries when they came through the Exotic Plant Pest Hotline; and coordinating communications.

As we know, there has also been a detection at Silverlake Reserve in Highbury as well. The priority of the response program is really twofold: it's to protect amenity tree plantings through the urgent removal of infested trees, as well as to protect, to the extent possible, our forest industries. The removal includes the infested trees but also the adjacent trees to create a buffer, because the pest can move through the adjoining crowns of the trees.

Removal of the affected trees remains the best known option for eliminating giant pine scale and is regarded as the quickest and most effective eradication method against the pest. Tree removal also assists in preventing the pest from spreading to other unaffected pines. As the opposition perhaps isn't aware, Minister Champion announced $1 million in funding for revegetating the area around the Hope Valley Reservoir, which was affected by GPS.

On 6 June last year, PIRSA and AFPA hosted a GPS stakeholder workshop to continue building a shared understanding of the potential risks of GPS and to define the roles, responsibilities, key actions and resources required in the event of an outbreak. The key message to participants was that South Australia's biosecurity system relies on a partnership approach between government, industry and the community. I think we have talked about it here on a number of occasions, that biosecurity generally is everyone's responsibility. Whether you are a landowner, producer, manufacturer, transporter, tourist or indeed a member of the community, we all have a role to play.

The workshop was well attended, with participants from various local councils, Green Adelaide, industry and government agencies. An outcome of the workshop was the establishment of a wider GPS network for stakeholders to stay informed and the beginning of the collaboration of GPS surveillance with a local council.

Members interjecting:

The Hon. C.M. SCRIVEN: If you are not interested in the answer, you shouldn't have asked the question.

The PRESIDENT: I am sure the minister is almost ready to conclude.

The Hon. C.M. SCRIVEN: This is an opposition question; it's not a government question—

Members interjecting:

The PRESIDENT: Order!

The Hon. C.M. SCRIVEN: —and yet we have complaints from the opposition because we are giving a fulsome answer.

Members interjecting:

The PRESIDENT: Order!

The Hon. C.M. SCRIVEN: You would think they would want to hear a fulsome answer, but apparently not. So it comes back to, essentially, the issue that addressing giant pine scale is complex because it is dependent on the ownership of the land. In some of the areas that we have been talking about, it might be owned by one agency but under the care and control of council or of a different agency, and there is also of course the issue of private property.

So we continue to work through this. The eradication is something that is being worked through across, as I said, industry as well as councils and government agencies. If there is a further update that I can provide, I will be happy to do so in the future.