Margo Sullivan feels lucky to call Mataranka home.
The small outback community in the Northern Territory, about 400 kilometres south-east of Darwin, attracts thousands of visitors each year and is famous for its thermal springs.
"It's somewhere that people can come, relax and be surrounded by Australian nature, rather than the sounds of cities," Ms Sullivan said.
For most of her life, the young pastoralist has lived on a small cattle station on the outskirts of town, along the banks of the Waterhouse River.
Now she feels the "pristine" natural beauty of the region could be lost if a rapidly spreading weed isn't controlled.
"You can really see the neem trees starting to take over … they grow really thick, choking out a lot of the native vegetation."
An invasive weed takes hold
Neem trees are widely spread across northern Australia, after being deliberately introduced as a shady ornamental tree that was also used to produce insecticide.
But in 2014, the trees were declared a class B weed in the Northern Territory.
That means the weed is required to be controlled, but there is no plan for its eradication.
Doris Baylis, from Mataranka Station, is the secretary of the Roper River Landcare Group.
"I don't know that people realise how invasive it is," she said.
"Once you get closer to the river, you start seeing monocultures – all you see are neems."
The pastoral landcare group is made up of property owners, land managers and local residents, and has won a national landcare award for its efforts to make the community of Mataranka "neem-free in 2023".
"In the community, we shouldn't have any problems … it's your river corridors where it's going to be much harder to get rid of [neem trees]," Ms Baylis said.
"But if [landholders] make an effort to get rid of neems on their properties, it is possible and we're doing it step by step.
"We do have to take control at some stage ... if we don't, we will end up with a much broader landscape of neem trees instead of a landscape that the Northern Territory is proud to say is pristine."
Below the Berrimah line
Margo Sullivan said neem trees, along with other weeds like bellyache bush, were sometimes overlooked by government.
"It does feel like sometimes if it's not impacting the greater Darwin region, it's not something the government's too interested in looking at," she said.
"A lot of these weeds get thrown in the too hard basket."
The NT government currently funds the Gamba Army's efforts to tackle gamba grass, mostly in Darwin's urban and rural areas, and the federal government has also committed almost $10 million to fight the highly invasive weed.
Ms Sullivan said it was difficult for landholders to manage weeds with limited time and resources, but the landcare group was working to support and educate locals about the impact of neem trees.
"It's a big ask for someone to outlay a lot of money, getting rid of a weed that probably doesn't affect their production so much – but it is really impacting the environment," she said.
"[But] you need everyone on board, because you only need one person not to engage with getting rid of neems, and their block acts as a seeding block for everyone else's – and you just end up with a continuous battle and you're never able to get rid of the source.
"If the same effort was put into resources for neems and some other weeds as it is for gamba grass, you'd really start to make a difference."
Fears of further spread
Local tourism operator and landcare member Des Barritt said neem trees would spread hundreds of kilometres along the river to communities in south-east Arnhem Land without further control.
"If you had a magic wand and the government had a heap of money, [the river corridor] is where you would be focusing efforts," Mr Barritt said.
"But [the landcare group] doesn't have the resources for that … and the government is never going to have the money to do it.
"We're just doing what we can do."
Ms Sullivan has already seen how neem trees have spread along the Waterhouse River.
"We're starting to find neems in areas we hadn't seen before," she said.
"They're working their way further and further up the river."
She said if the weed wasn't controlled, future generations would be left with a "sea of neems".
"They'll never get to see the rivers and the springs and all the native vegetation as it should be in all its glory," Ms Sullivan said.
"All the pristine Australian landscapes that are so stereotypical of this area, they won't exist anymore and that'd be sad."
