Controlling Kunzea in Halls Gap

Project dates: June 2019 - December 2023

Kunzea (Kunzea leptospermoides, also known as Yarra burgan), is a tall (2-5 [<15]m) native shrub originating from eastern Victoria and the NSW coastal hinterland. It is not indigenous to Halls Gap or Gariwerd (the Grampians Ranges). Kunzea was introduced to the region as an ornamental garden plant and has since spread through Halls Gap, forming dense thickets which are a biodiversity threat and potential fire hazard. Unchecked, there is potential for this pest plant to spread from private property into the surrounding National Park.

We are teaming up with the Halls Gap Landcare to map and remove the infestations, and replant affected areas with locally native species. We are working to eradicate Kunzea in Halls Gap.

The site

Halls Gap is a popular tourist town in Western Vic, nestled in Gariwerd (the Grampians Ranges), which is considered an extremely significant floristically diverse region that has been protected as the Grampians National Park. It contains a whopping one third of Victoria's total plant biodiversity, including many species that are found nowhere else. With a small population of around 400-450, many of the properties in Halls Gap are tourist accommodations or are owned by absentee landholders.

What we are doing

Mapping

The first critical step in our approach involved detailed mapping of the Kunzea infestations within the Halls Gap township. This mapping is essential for ensuring that our efforts are efficiently focused on the areas presenting the greatest risk to biodiversity and fire intensity. Kunzea was first flagged as a species of concern by Parks Victoria, and after discussions with Parks and other stakeholders, Project Platypus received a Biodiversity On-Ground Action (BOA) grant which allowed for initial mapping in the Halls Gap area to be conducted. All sites identified control were photographed, to allow evaluation of success after Kunzea removal and revegetation was complete.

Community empowerment

Project Platypus' early discussions with community members while planning this project led to the establishment of our newest Landcare group - the Halls Gap Landcare! This new Landcare immediately put their local knowledge about the occurrence and extent of this invasive species and their local networks to use. They led the charge on landholder outreach, in particular focusing on securing permissions from absentee landholders for weed control works at priority sites, as well as providing education to the community on biodiversity friendly landscaping choices. Now the Landcare group plays a pivotal role in rallying their community to embrace their role as stewards of the unique and beloved biodiversity of Gariwerd (the Grampians Ranges).

Removal of infestations

The largest component of this project has been the physical removal of several significant infestations of Kunzea within Halls Gap. At over 30 sites, mature Kunzea plants were hand cut and painted with herbicide, while smaller plants were controlled with herbicide (using a foliar spray) where possible. All removed vegetation was chipped and mulched back over the treated area. This technique effectively suppresses regrowth/regeneration of the Kunzea plant.

Revegetation

Our work was not done after the removal of the Kunzea plants. Weed removal can leave large bare patches behind that are perfect for further establishment of weedy species, if no intervention is made. We take a proactive approach of replanting the areas cleared of Kunzea with locally native species, restoring the natural habitat while also prevent the re-emergence of the invasive species.

The images below show the impressive outcomes of these Kunzea removal, and native revegetation efforts. You can see the immediate reduction in fire risk. Through time, as the newly planted native plants mature, you will also see the increase in biodiversity that results from replacing an infestation of a single weed species with a more balanced mix of native species.

Funding acknowledgements

Funding provided by the R E Ross Trust through their Biodiversity Conservation Smart Grant program

Controlling Kunzea in Halls Gap

Protecting Gariwerd/Grampians National Park from an invasive weed

We are teaming up with the Halls Gap Landcare to map and remove the infestations, and replant affected areas with locally native species. We are working to eradicate Kunzea in Halls Gap.

The site

What we are doing

Funding acknowledgements