Trial looks at putting whenua first

The Mangatea Stream that passes through the farm of the same name has always been a food source for Maori of the area, yet its significance runs even deeper than its ability to sustain the people.

The 200ha Mangatea farm is owned by Tainui Group Holdings and is milking 580 cows. TGH owns over 4000 hectares of Waikato land that supports dairy, sheep, beef, and forestry operations on behalf of its tribal owners.

Mangatea is among 10 Waikato and Bay of Plenty farms entering a new era through a $2.7 million trial called Rere ki Uta Rere ki Tai.

A science-based research project, it merges indigenous knowledge and regenerative agriculture principles to test if soil and waterway health can be improved, while maintaining profitable dairy farming.

The whenua, the land, is the life blood of the people, says Ngati Wairere kaumatua George Hopa, who embraced the trial at Mangatea farm.

"It feeds us, it takes care of us, without the whenua we wouldn't survive, none of us. I'm looking at it from a global way, and with farming, that's what it still means to me."

Hopa has lived on the whenua all his life and is a recipient of the Ahuwhenua Trophy for excellence in Maori farming,

He says the land and river here was rich in resources - birds, plentiful freshwater aqua life, fertile soil and clean waters.

"In the Mangatea, there was the tuna, there was the koura, there was the kokopu and all the aqua life that lived there. We are fortunate that they are still there today. Even I, three weeks ago, had a smoked tuna so we are fortunate that our awa, our river, the Mangatea, still provides … it's like a market garden.

"The whenua, the land, is the life blood of our people.

"I think it's up to everybody to make sure that they look after their waters, the waterway. It doesn't matter where you are, whether you turn the tap on in Auckland and let it go to waste. It's the life force, the water, and the whenua."

At the heart of Rere ki uta Rere ki Tai is the mana and mauri of the soil.

Research aims to find out whether using farming methods that move away from synthetic fertiliser and sewing a more diverse pasture crop among other changes leads to more resilient, profitable farms that better withstand environmental, societal and regulatory pressure.

The health of the soil, of waterways on farms and the wellbeing of farmers themselves will be monitored over two years, as will the costs or savings of replacing synthetic fertiliser with seaweed-based biostimulants in some areas on farm.

The project is led by AgriSea, a seaweed innovation company in Paeroa in the Hauraki.

Mozz Trueman is implementing the changes on the ground after consulting with manawhenua about aspirations as soon as he arrived as dairy and support operations manager for TGH in late 2021.

"I met George, and he was like a living encyclopaedia who knows every blade of grass, so I've turned to him for guidance," Trueman says.

"It was a push from George as one of his big visions to get their people back into the whenua and harvesting like they used to."

Tied into the significance of the land is the history of tribes that trace their ancestry back to the voyagers on the Tainui waka.

Half-a-million hectares of Waikato land was confiscated by the Crown in 1865 from those who had settled in this part of the North Island for hundreds of years. The Mangatea stream is the boundary line marking the small amount that was returned to its tribal owners.

Hopa's great-great grandfather and a Rangatira chief Pirihi Tomanui tried to negotiate with the Crown in 1865 to get back 8000ha but only 650ha was returned. The opportunity to farm the lands began in the 1930s through Maori Affairs. Dairying has intensified over the decades since.

Trueman said the vulnerabilities of this system became obvious to him during the pandemic when importing feed became a challenge.

"The big goal is to keep everything in-house and not bring anything in. Part of this means reducing stock levels, while trying to increase productivity through nutrition in the soil and pasture," he says.

"I'm quite excited about the new road we're taking starting from next season. We're a high input farm, we bring maize in and decreasing the stocking rate means we'll have less cost and better fed cows with less competition, it's just tweaking the system to be more sustainable."

The herd is not only being reduced in number but switched from the big Friesian to a KiwiCross breed cow.

TGH is setting a big 10m buffer zone around the waterways with native planting beginning shortly in a programme partly supported by Waikato Regional Council.

High-risk areas of land such as 60ha of a steeper hillside where effluent and standard nitrogen fertiliser can wash off into the Mangatea stream will be set aside for aerial application of AgriSea biostimulants, as part of the trial.

Rather than cutting into the soil, seed will be direct drilled, meaning the seed is sewed directly in the residues of the previous crop with minimal soil disruption. This retains soil structure and moisture, reduces erosion and reduces the likelihood of worms and other important creatures living within the soil being chopped up in the process of ploughing it.

"I think sometimes in dairy farming you're only looking at what's on top of the ground and at growth rates, driven by profit," Trueman said. "Companies will come and do herbage tests, but sometimes it's about taking a step back and having a look at what's going on under the soil.

"AgriSea have come in and I've learned quite a lot from them, especially when it comes to worm population. We've gone away from fully cultivating pastures to direct drilling and not turning the soil over, which doesn't diminish the soil or cut the worm population. We're seeing really good results from that in the crops we're doing."

The whanau-based intergenerational model of management that is active across AgriSea is also brought to Rere Ki Uta, Rere Ki Tai.

AgriSea chief innovation officer Tane Bradley says the research is a pathway for each farm's approach to honouring the mana and mauri of soil on their whenua.

"Our kaimahi pamu [farmers] come from conventional and organic farms, farms under iwi and private Maori and Pakeha ownership, new farms and intergenerational farms, and farms supplying Fonterra, Synlait and Miraka. Each farm has its own unique history, values, and taiao.

"Weaving together matauranga, intergenerational knowledge, farming experience, and science, Rere ki Uta, Rere ki Tai is building farming systems that work with rather than against natural systems, understanding and respecting the cycle of te Taiao [our natural world] and our reciprocal role," he says.

This research project is funded for two years by Our Land and Water National Science Challenge as part of the Revitalise Te Taiao research programme and hosted by AgriSea.