Cloncurry Shire Council has taken action against the "fast-spreading" weed leucaena, passing a local law to declare it as a pest in order to contain its growing impact on council and private land.
Leucaena leucocephala is a source of feed for cattle, but there are concerns it is quickly getting out of control across northern Queensland.
On December 12, council resolved to declare the weed as a local pest for the whole Cloncurry Shire area.
Mayor Greg Campbell said while council was already working to control it on council land, there was a need for management on state and private land.
"It's been around for a while, but the type of plant it is, it's a prolific seeder, therefore it spreads rapidly and strongly - especially around town in residential lots, areas around the rail corridor, the road corridor," he said.
"It's starting to be noticeable how thick it's getting.
"(We) strongly encourage...people to control it on private land before it gets into the Cloncurry River and essentially into the Gulf of Carpentaria. It has to be controlled and contained because it can escape and get away.
"If it's not controlled, it starts to have an impact on our natural ecosystems...the local law we passed was to give us the power to do more to control it around town."
Cr Campbell said council will target transport corridors like government-owned land along the railway line, where the core infestations have been located.
The law will allow council to clean up infestations on private land and pass on the cost to landowners if the weeds are privately managed.
"As a rural shire, we also see that there's a great potential to expand the efficiency of our grazing enterprises. It's recognised, especially where it's used in a rural enterprise, as a really worthwhile protein crop (for cattle)."
While the weed had not had a "huge impact on agriculture at the present", its fast-spreading ability and durability meant it was hard to manage once it had taken hold.
"There are not many plants where you can cut them off literally at ground level and after a big wet, they're as big as they were before," Cr Campbell said.
"The only way to control them is to poison but because it spreads and grows so quickly, we need to keep (on top of it) and keep it out of our essentially pristine waterways.
"It's an extremely tough plant...it can suffer the effects of the heat and dry, but every time we get a decent wet season, you see it spreading more and more. Unlike other weeds, it doesn't need a wet season to keep spreading."
Sterile variety research
Cr Campbell said for the last few years, council had been working with researchers from the University of Queensland, including Professor Christopher Lambrides, who are developing a sterile variety of leucaena.
"We'd like to see that come off and be commercially available because of the true benefits of what it does for weight gain with cattle...it'd be awesome for graziers not just in Cloncurry but in the north west in general," he said.
"UQ have got an open offers to do trials on council land. The potential, especially for the beef industry - if they can nail that, making a hybrid that is pretty much sterile, will be a game changer.
"Council is committed to leading the way...to facilitate and enable our landowners to make sure we are as weed-free as possible as a shire.
"We have lot less (weeds) than some of our southern neighbours, so want to keep on the front foot and kill as many as can."
Biosecurity obligations
A Department of Agriculture spokesperson said a general biosecurity obligation existed for leucaena, that required the person dealing with it to manage the biosecurity risks where reasonable and practical.
"Under local law a local government in Queensland can declare leucaena where a need exists at a local level to manage the spread of the leucaena from grazing pastures," they said.
Noting that it was a valuable legume fodder crop that provided high-quality feed for ruminant animals, they also commented that it was an invasive plant in parts of the state.
"The department supports the Leucaena Network "Code of Practice for Managing the Weed Potential of Grazed Leucaena Pastures" to help prevent the spread of leucaena outside areas used for grazing," a DAF statement said.
"The code makes it clear that leucaena should only be planted in areas for the purpose of highly managed and well-contained forage.
"It should not be planted in areas where rivers, creeks or flood channels could lead to seed dispersal and should be kept at least 20 metres away from external fence lines."
It said more details could be found in the code of practice.
