Locals join fight against invasive arum lily

Ann Ward in an area she is revegetating following steps taken to control arum lily on her property. Photo supplied.
Ann Ward in an area she is revegetating following steps taken to control arum lily on her property. Photo supplied.

Landholders across the Margaret River region are closing in on the invasive arum lily, with hundreds of properties and thousands of hectares treated and an open invite for everyone to join a newly-launched State Government-funded control effort.

With $340,360 in funding from the WA Government's State Natural Resource Management Program, the Arum Lily Blitz is bringing together local and State Government agencies, environmental organisations and private landholders in a coordinated, concerted and sustained push aimed at controlling this toxic weed.

Nature Conservation has already worked with more than 300 landholders across 3500ha in recent years, and are inviting more to take part.

Blitz participants will be joining the likes of Ann Ward, who purchased an arum lily-riddled property on the Margaret River in 2017.

"At first it seemed overwhelming, until I realised there was a simple solution," she said.

The following year, Dr Ward enlisted the help of Nature Conservation for a single spray event that proved "very, very successful". "About 95 per cent didn't come back," she said.

"Small follow up sprays will be needed over the next few years but the hard work is done. Now I'm able to replant the area to encourage biodiversity and hopefully help restore some health to this part of the country."

Dr Ward believes more people would get involved if they understood why it was important, the nature of the problem and how easily the plant could be combatted.

Arum lily was introduced from South Africa and now runs rampant across the region, choking native vegetation, reducing the availability of food for wildlife, and forming thick, unsightly monocultures where diverse native plant communities should be.

It is a major threat to the South West's biodiversity and is also poisonous to pets, livestock and people.

Despite being a hardy species that reproduces and spreads easily, the plant itself is easy to kill.

Few know this better than Bill Castleden, who has been battling arum lily for 20 years.

At first, he tried slashing the whole plant to the ground during flowering - a technique that proved to be "a complete failure" - but then turned to Nature Conservation for help.

Mr Castleden said he was motivated to get rid of the lilies because he was concerned about the noxious weed spreading into bushland.

But while arum lily is easy to control, Mr Castleden conceded localised action was only effective long-term with everyone on board.

"I think others fail to get involved because they are unaware of the threat, or that there is help available," he said.

Keith McLeod is another local who has been battling arum lily and - like Mr Castleden - said all landholders needed to come together.

"The issue is, you might have one property trying to control lilies, but across the boundary line, they might be everywhere," he said.

"And birds don't see fence lines as a boundary; they just perch in a tree, drop the seeds and you've got arum lily spreading again," he said.

Mr McLeod undertakes yearly maintenance on his property, but was optimistic that a coordinated approach could stop the spread in its tracks.

"This is a really great program they've got going and I hope, that with everyone chipping away and doing their part, we'll be able to make a difference," he said.

Nature Conservation project officer Genevieve Hanran-Smith said landholders could undertake spraying themselves - with free herbicide and easy-to-follow instructions to be provided - or hire an experienced, recommended contractor for a subsidised fee.

"There are numerous reasons some people haven't acted yet," she said. "It might be because they're time poor, don't live locally, are unsure what to do, or perhaps aren't aware how their lack of action is affecting their neighbours.

"But we aim to make it easy for people to get involved and have all the resources they need to get started. The first step is heading to natureconservation.org.au to register and get further information."