The country's greenest farmers are concerned by Government plans to charge them for emissions.
That's because some have already spent thousands cleaning their land, and paying more could cripple their business.
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Ten minutes south of Matamata in Waikato is Dennley Farms. It's 200 hectares of land, home to dairy cows and beef cattle, owned by Pauline and Adrian Ball, recently crowned New Zealand's greenest farmers.
"It has become quite clear to us that our competitive advantage on the world stage is our natural resources and how we look after them," Adrian said.
The Balls are "early adopters" - farmers who acknowledged climate change early.
For example, a block of land is powered by solar panels. They've also put more beef cattle on it, which are less intensive than just dairy cows.
"Just the deintensification, using these dairy beef animals more efficiently helps with climate change."
They're also importing less harmful stock feed, recycle dirty water and plant trees to look after the Waihou River.
Over the last three years, the Balls have planted more than 6200 native trees. The idea is they'll filter the nitrate from the soil but they'll also stop the sediment running into the waterway.
They've managed a 40 percent reduction in CO2 emissions.
It's meant retiring a lot of land, but they say farming can't be all about earning money.
"We tend to look at all the bottom lines of sustainability so there's no point in us making a huge amount of money if we are destroying our natural resources."
It's cost them thousands though to turn green. They're now worried about having to pay more in coming years as the Government announced it will start charging all farmers for emissions by 2025.
They'll also all need to do more to reach the Government's zero-carbon goals.
"Yeah well early adopter have done it voluntarily, so if they have to scale back again, it almost compromises their business."
But after taking their concerns to Climate Change Minister James Shaw, the Balls have been told their efforts won't go unnoticed.
"In fact, this scheme as it gets designed should ensure those people see some financial benefit," Shaw said.
Shaw says just what that financial benefit looks like is still to be determined.
The Balls are pleased to hear that, but they'll continue to farm sustainably regardless.