Mount Eliza Escarpment Project
Necessary changes to the Mount Eliza escarpment will soon see the area reimagined.
Updated April 2024.
A necessary biosecurity response
Ongoing surveillance at Kings Park identified trees on the escarpment displaying signs of the invasive pest Polyphagous shot-hole borer (PSHB).
What does this mean? Explained by our arborist
What is PSHB?
2021 saw the arrival of the declared pest Polyphagous shot-hole borer (PSHB) to the Perth region. PSHB is a beetle native to Southeast Asia. The beetle attacks a wide range of trees by tunnelling into trunks, stems and branches.
About the size of a sesame seed, PSHB excavates tunnels in trees where they cultivate a Fusarium fungus as a food source. This fungus spreads in the tunnels blocking the flow of water and nutrients in the tree. This blockage causes trees to become unsafe, and eventually die. If not removed, trees infested by PSHB can become a constant source of beetles that disperse and impact neighbouring trees.
There are no effective chemical treatment options available.
What is the risk to Kings Park and our flora?
The risk to our Western Australian Botanic Garden, natural landscape features across Kings Park and to the safety of visitors is real if we don't take action.
The Mounts Bay Road location of the trees identified with PSHB is in close proximity to the Western Australian Botanic Garden and the many rare and endangered flora protected in its collection.
Unless decisive action is taken, these infested trees will spread the beetles beyond the escarpment boundary, putting at risk the vital Perth asset of Kings Park and also the urban canopy of the surrounding suburbs.
The progression of the infestation also poses a future risk to visitors from dead and dying branches if the infested trees are not removed promptly.
A special place
Mount Eliza escarpment is a special place in the hearts of Kings Park visitors and locals. The escarpment rises steeply from the Swan River to a high point in the landscape of 65 m, with popular features including the Kokoda Track and Lover's Walk. The area is recognised for its significance to Whadjuk Noongar Traditional owners as well as its post-colonial landscape features.
The Botanic Gardens and Parks Authority (BGPA) has maintained the escarpment and landscape values over many decades for the enjoyment of our community.
Taking action to protect Kings Park
Sadly, the severity of the infestation requires the removal of all infested trees.
Mounts Bay Gardens - current status
Works to remove infested Moreton Bay and Port Jackson Figs from Mounts Bay Gardens (located adjacent to the Kokoda Steps) have now been completed.
The area is sectioned off and not available for public access.
Ongoing surveillance – current status
Surveillance is ongoing at Kings Park and along Mount Eliza escarpment. Any additional infested trees will continue to be managed as appropriate, including removal if required.
Restoration for the future
The tree removals are not the end! BGPA will work to restore the Mount Eliza escarpment.
These necessary landscape changes have provided the opportunity to ‘reimagine’ this popular area with a focus on culture, native plantings and greater visitor amenity.
Putting the focus on culture
BGPA and the Department of Primary Industries and Regional Development (DPIRD) recognise the significance of this site to Traditional Owners. All efforts are being made before, during and after the project to consult Whadjuk Noongar Traditional Owners and protect cultural heritage.
The next step seeks to create an environment that reflects Whadjuk Noongar culture, history, and values and reestablish Mount Eliza escarpment as a meaningful connection between Kings Park and the Swan River.
Why native plantings are so important
Biosecurity and climate change are becoming greater challenges every day. Local flora species are much more resilient to threats as well as vital habitat and food for our native animals and birds. Once the trees are removed, we're putting our focus on restoration for our future.
Frequently Asked Questions
What Traditional Owner engagement has been undertaken?
BGPA and DPIRD recognise the significance of Mount Eliza and Mounts Bay Gardens (Goonininup) to the Whadjuk Noongar people and all efforts will be made to preserve the traditional heritage of the site.
- Goonininup – The freshwater spring is of significant spiritual heritage as it is associated with the home of the Rainbow Serpent, the Waugal. Its waters are considered sacred.
- Mount Eliza – The area was used as a gathering place for water, food, ceremony, communication, and trade.
BGPA engaged South West Aboriginal Land and Sea Council (SWALSC) to provide advice on the project operations. Through SWALSC, representatives from the Whadjuk Noongar community were, and continue to be, consulted by BGPA and DPIRD prior to the tree removals commencing. BGPA will continue to engage with Traditional Owners as we look to the future of Mount Eliza and Mounts Bay Gardens (Goonininup) and protecting and celebrating its cultural heritage.
Is PSHB local to Kings Park?
DPIRD is responding to the confirmed detections in the Perth metropolitan area. BGPA is coordinating an internal response to limit spread of PSHB in Kings Park and Bold Park. This involves a response by BGPA staff and volunteers, and working closely with our colleagues at DPIRD, DBCA and other key stakeholders.
The removal of infested trees is key to containing PSHB spread and minimising further impact on neighbouring trees.
We encourage everyone to be on the lookout for PSHB damage in their communities and to report observations of suspect borer activity.
Will there be closures?
Mounts Bay Gardens (Goonininup) is closed to pedestrian and vehicle access.
Will this affect the slope stability?
Recent assessment of the escarpment has indicated that the slopes have undergone relatively minor erosion and deterioration. BGPA is managing the increased instability risk presented by tree removals through ongoing consultation with GHD (geotechnical engineers), as well as regular assessments. Public safety measures will be in place for the duration of the project, including exclusion zones and rock catch fences. An exclusion zone will remain in place at Mounts Bay Gardens (Goonininup) following the works to manage public safety.
What will happen to the fauna?
The majority of the tree removals will affect Moreton Bay Figs, which mainly support lorikeets and foxes. Reimagining the area with Western Australian plantings provides the opportunity for us to provide greater support for our native fauna into the future.
What will Mount Eliza and Mounts Bay Gardens (Goonininup) look like in future?
The first stage of the project is to control the immediate threat of PSHB. Once tree removals have been completed, BGPA will begin a process of assessment, planning, consultation and co-design to create a new vision for this much-loved area. This webpage will be updated as the project progresses.
What is being done to combat PSHB?
The Department of Primary Industries and Regional Development is managing the response to confirmed detections of PSHB.
Visit the DPIRD website for information on the beetle and biosecurity response.
How do I report PSHB?
Suspected PSHB sightings can be reported:
DPIRD Pest and Disease Information Service
MyPestGuideTM