A conservation charity claims the survival of iconic native trees like Pohutukawa and Rata depend on the use of 1080.
It says if New Zealand were to stop aerial drops, it would change the country's eco-system forever.
It's known as the Kiwi Christmas tree but 30 years ago possums and other pests had almost wiped the country clean of Pohutukawa trees.
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"1080 has been a game changer for protecting the trees," Project Crimson CEO Adele Fitzpatrick told Newshub.
"Possums devastate our native trees when left to their own devices.
"They're just their favourite delicacy and possums can go through 20,000 tonnes of foliage in a night. That's equal to around 450 fully laden logging trucks every night."
Project Crimson is concerned that if 1080 wasn't used any more our native plants would suffer.
"We would lose our native wildlife and our trees. Without our native trees there's no habitat for our native birds, three's no forests, there's no insects," Ms Fitzpatrick said.
But Nelson-based environmental lawyer and 1080 opponent Sue Grey disagrees.
"There are many better ways of protecting our native plants and our animals than aerially depositing 1080 into our rivers onto our riverbeds where there is a lot of by-kill of species."
Ms Grey says that relies on being able to have open discussion.
"How can we do this better? How can we make a sustainable solution so we can have a clean-green New Zealand that we can all be proud of, instead of this civil war going on between pro-poisoners and the anti-poisoners?"
However long that may take, Project Crimson says we can't stop using 1080 in the interim, because despite it being a blunt tool, it's the only one that works.