Intensive dairy farming threatens NZ's clean, green image: Greenpeace
Industrial dairying: It's a label that evokes the worst of the industry.
Critics talk of over-stocked paddocks of cows fed masses of palm kernel brought into farms that depend on irrigation to survive.
Certainly, the statistics from dairy organisation DairyNZ show how the industry has evolved.
Herd numbers have shrunk, but herd sizes have more than doubled. Cow numbers have increased and the total effective hectares used to milk has climbed by 750,000 since 1985-86.
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In that season, there were 15,753 herds and 2.3 million cows, milking just over 1m hectares. By 2001-2002, herd numbers had dropped to 13,649, cow numbers had increased to nearly 3.7m, and the total effective hectares jumped to 1.4m.
Today, herd numbers have dropped to 11,918, total cow numbers are just under 5m and dairy land has expanded to 1.75m hectares. Herd sizes have grown to an average of 419 cows.
The numbers tell us that New Zealand's cow footprint has expanded and intensified, but is it fair to paint this development as industrial dairying?
It's a term that both bemuses and annoys Rex Butterworth.
Butterworth and wife Sharon farm at Walton, near Matamata, in the Waikato. Their farm business consists of a 106ha milking platform and a 52ha runoff at a stocking rate of 4.5 cows per hectare.
They underwent a $900,000 infrastructure development on their 158ha farm, which included two cow-housing structures built by Herd Homes starting in 2012-2013.
They made the call to change their farming system after several years of being hit financially and environmentally by summer drought and winter rain. Butterworth says the industrial dairying label wouldn't fit many farms in New Zealand.
"I don't consider myself an industrial dairy farmer. I do consider that I need to be a commercially viable business and I have to be environmentally responsible and I don't mind that at all."
The Herd Homes allow him to capture all of the animal dung and urine from their 480-cow herd, which is then redistributed as fertiliser on to their maize block at the runoff property. That crop is then used as supplementary feed for the cows, making up about 40 per cent of their diet.
The housing gives the herd a place that is warm and dry in the winter and cool and shady in the summer.
"We have a lower environmental footprint than the type of farming they [critics] would be promoting. We are running about a 25 per cent lower [environmental] impact than a more traditional farm with a low stocking rate."
His efforts saw him named Dairy Business of the Year runner-up last year.
"I'm way happier at how my cows are treated now than how I was able to treat them 10 years ago and I was doing my best 10 years ago and I'm doing my best today."
In hindsight, Butterworth believes that the dairy industry moved too fast in the past decade, when changes were occurring across the country around compliance.
"The two came together - extreme growth and a realisation that what we were doing wasn't good enough and that we need to do better.
"I think there is a cap for the number of cows we can have in New Zealand without having a negative environmental impact and if we are going to carry on dairy farming in New Zealand, we are going to have to do it differently from the past."
Butterworth says his system delivered on many of the environmental targets sought by Greenpeace and other environmental groups.
"Yet they're slamming it."
Greenpeace sustainable agriculture campaigner Genevieve Toop says farmers using high-input systems like the Butterworths are heading in a direction New Zealand agriculture should not be heading.
It relies on its clean, green image for its brand value and these types of farm systems threaten this image.
While these systems may leach low levels of nutrients, they still have high biological greenhouse gas emissions.
"It's very simple: The more dairy cows there are, the more biological emissions there are. We believe that with low input and more ecological farming practices, we can have a more profitable farming sector."
Toop says her organisation is not labelling all dairy farmers as industrial farmers.
However, farms modelled around high inputs and stocking rates that are supported by irrigation are causing havoc to the country's waterways.
It's these systems that are industrialised dairying, she says.
"We are not saying all dairying is bad, we are saying [it is] a certain model and that model is industrial."
Butterworth has a contrasting view. He says it is unrealistic to expect every dairy farm to switch to this type of farming, a stance also backed by DairyNZ strategy and investment leader for productivity Dr Bruce Thorrold.
Thorrold is a fan of using science to work out the balance between running farms as viable businesses and reducing their environmental footprint.
Limiting dairying to one type of farm system based on a low stocking rate and inputs ignores the different challenges each region faces.
Northland, for example, is characterised by warm winters, drought-like summers and low-quality kikuyu grass. Contrast that with farming in Canterbury, which has irrigation water, very cold winters and a reliable pasture-growth season.
"Why would we say that in those two places, you have got to farm the same way?"
Low input model a success for the Lincoln University Dairy Farm
One farm that successfully switched to a low-input system is the Lincoln University Dairy Farm (LUDF).
South Island Dairy Development Centre executive director Ron Pellow says LUDF managers wanted to lower the centre's environmental footprint and change from a system based on a high stocking rate of 4.2 cows a hectare and feeding the cows pasture first.
Pellow says they wanted to challenge themselves to do a better job of improving their environmental footprint while retaining their profitability.
The stocking rate was reduced to 3.9 cows a hectare and the team concentrated on growing more grass through regrassing and more fertiliser applications to feed the cows better.
In 2014-15, managers dropped cow numbers further to 3.5 cows as well as further lowering their silage intake and fertiliser usage while hoping to maintain production levels and profitability.
By lowering inputs, LUDF still achieved a sustainable profit with a lower environmental footprint. The farm leaches 20 per cent less nitrogen per hectare and has lowered the total nitrogen lost in the catchment because of efficiencies in the system.
Milk production per cow has lifted while overall production has remained steady.
"We have effectively got the same amount of production from fewer cows, but a more efficient overall system, and that's about using our grass better because we have about the same amount of grass but we can portion it better between maintenance and lactation."
"The number of people watching, following and adopting [LUDF] is quite significant. Farmers are people and they like to see evidence that is applicable to themselves and what we have shown at LUDF is that if we can do it then it's more probable that other people can do it as well."
Pellow says LUDF's system and higher input systems used by Butterworth have found ways of lowering their nutrient footprints in different ways.
"There is no right answer. All farms are different to a degree and will choose different routes and strategies of addressing opportunities."
Tipu Whenua farm consultant Alison Dewes says her research shows that the most resilient farm systems are those which are not over-stocked and not reliant on brought-in feed. In a lot of cases, farms are stocked about 20 per cent above what they need to be for a long-term $5.50/kg milk solids milk price.
This creates huge tension between farmers and environmental groups. Farmers have become more dependent on brought-in feed and this is used to support stocking rates above optimum.
"One could argue that if we truly want to get back to a pasture-based system, we probably do need to de-stock quite a lot of farms."
While she supports Butterworth's system, switching to a less intensive system from both a farm operator and cow perspective is healthier.
"We have a lot of mental stress in the industry and we have got animal welfare issues, and we have overshot the mark in terms of intensity, which puts stress on people and animals."
In the Broadlands area in South Waikato the typical stocking rate is about 2.8 cows a hectare, or 1300kg of body weight a hectare. On the most resilient farms, that stocking rate was closer to 1100kg of body weight, she says.
Farmers need to shift their thinking from the current cows per hectare model to matching the livestock's body weight per hectare with what the land can handle. This is because of the variability in cow weights, Dewes says.
Turning it into a conversation around stocking rate is a simple way of addressing the concerns urban people have around water quality, Dewes says.
Science is the answer - DairyNZ
Scaling back land use is one solution to improving dairying's environmental footprint. The other, Thorrold says, is "sciencing our way out of it".
That means taking the farm systems used by Pellow and Butterworth and using new and emerging science so that dairy farmers can 'have their cake and eat it, too, he says.
"That's what we are after and to constrain ourselves down to 'there is only one solution and it's dairy farms or pine trees', is really unhelpful."
Achieving this would be challenging, but Thorrold is confident science will succeed.
Problems around dairying's nutrient loading are not solved at a farm scale and that was where DairyNZ and groups such as Greenpeace come to an impasse, he says.
"By saying that the only acceptable solution to catchment problems is reducing cow numbers is take out of play all of the science and technology."
Modern, science-based farming is the solution in finding systems that are economically resilient and with a low environmental footprint.
But Toop says DairyNZ is making the issue more complex than it is.
The simple fact is that New Zealand has too many dairy cows as evidenced by the water quality in rivers. There are also dairy farms in areas where soils are not suited for them, such as the 'leaky' soils on the Canterbury Plains, she says.
DairyNZ is better off looking closer at low-input farming models rather than wasting time and money on "techno-fix" science, Toop says.
The Parliamentary Commissioner for the Environment's report around biological greenhouse gas emissions showed that none of the science projects to lower farming's footprint being pursued by groups such as DairyNZ are close to being ready.
"We can't wait for these techno-fixes to come."