Arum Lily Blitz engages over 1000 landowners

Excellent progress has been made in the second year of the three year Arum Lily Blitz with over 1000 landowners engaged in the project. The level of interest and commitment we’ve seen in the last two years inspires us to believe we can achieve the vision of arum lily being controlled in our region to protect biodiversity, agriculture and visual landscape values.

A quick snapshot of the progress made so far:

  • 1020 properties are currently registered as actively controlling arum lily across 16,100 hectares.
  •  479 people collected free herbicide in 2019 and 2020. We have so far had 357 reports from landholders providing data on their work which totals an impressive 2428 hours of arum lily control completed by landholders. At $35/hr that equals nearly $85,000 of landholder effort. And this data only represents a proportion of the work done! A huge effort and commitment across the region.
  • 90 landholders have been supported on a cost share basis to control arum lily in high priority areas. This has involved a total of 1700 hours of contractor work demonstrating a huge commitment from landholders to invest in managing arum lily on their properties.
  • We continue to work in close partnership with the Department of Biodiversity, Conservation and Attractions to share the cost of control in some areas of the Leeuwin-Naturaliste and Wooditjup National Parks. Areas of focus in 2019 and 2020 have been Wooditjup, Calgardup, Cowaramup, Prevelly, Moses Rock and Yallingup. 395 hours spraying has been completed in the National Park in the last two years. This strategic work is protecting vegetation quality in some areas of the National Park but there is a lot more work to be done to better understand the presence and extent of arum lily and to undertake control to reduce the impact on the many varied and beautiful native vegetation communities in the Park.
  • The Shire of Augusta Margaret River, City of Busselton and Margaret River Busselton Tourism Association continue to implement arum lily control programs. In the last two years these organisations have completed 1025 hours arum lily control.

Community volunteers working in the National Park
The Arum Lily Blitz project has encouraged and supported volunteers to undertake arum lily control in the Leeuwin-Naturaliste National Park. DBCA has been open to volunteers spraying in the National Park provided they are trained and meet requirements for OH&S, approvals and reporting. DBCA staff, especially Renee Ettridge, have provided excellent support to enable this to happen.

In 2018 Yallingup LCDC volunteers mapped arum lily density across 242 ha of National Park surrounding the Yallingup townsite. The mapping provided direction for control effort in 2019 and 2020. In 2020, 10 Yallingup volunteers spent 284 hours spraying arum lilies. They sprayed 2910 litres. This incredible volunteer effort equates to someone undertaking spraying as a full time job for over 7 and a half weeks.

In 2019 the Friends of the Cape to Cape Track volunteers mapped arum lily along the 124 km length of the Cape to Cape track. This year 18 volunteers did 152 volunteer hours work to control arum lily along the track. The Friends of the Cape to Cape Track also raised funds through donations to fund contractor control of larger infestations on the track at the Moses Rock campsite and other areas in this stretch.

We would like to acknowledge and thank the volunteers for this incredible effort. They are communitychampions.

Demonstrating effective arum lily control
The need for an arum lily control monitoring site to evaluate and demonstrate successful arum lily control was identified early in the project. A site in the National Park was identified, approvals given by DBCA and funding successfully sought from the community.

Density mapping using 20 x 20 quadrats, vegetation transects and photo point monitoring were established prior to spraying. In 2019 control was undertaken across approximately 13 ha. In 2020 the density mapping, vegetation transects and photo point monitoring were replicated. Follow up spraying was undertaken and the area of control extended to cover the rest of this infestation.

The follow up data showed an enormous reduction in arum lilies. It also sadly demonstrated the significant reduction in abundance and diversity of native flora once the density of an arum lily infestation crosses a threshold.

Thank you to Adrian Fini, Gavin Bunning, Bill Castelden, Penny Bower, Grant Johnston, Janet Holmes a Court, Gilbert George, Bill Breidhal and Phil Finch for contributing funding to make this work possible.