A suggestion that New Zealand should remove 80per cent of dairy cows to return to a natural environment overlooks various fundamental problems including: what is natural?
Dairy farms tend to be in flat to rolling countryside where grass grows well and cows can create milk efficiently.
It is in this country that clear mountain streams become winding rivers, picking up sediment and nutrients from the soils through which they are travelling. As they slow down, plants and fish have a chance to grow.
Dairying occupies 1.7 million hectares of New Zealand's 26.8 million hectares. This area, with the associated processing and value adding, resulted in export revenue for the year to June 2015 of $14 billion.
In some contrast, sheep, beef and deer farms cover 11.5 million hectares of mostly somewhat steeper land, and bring in $9 billion.
Replacing dairy cows with beef, sheep and deer would affect the economy negatively, meaning reduced funds for environmental protection, education and health as well as social welfare.
In addition, meat animals produce less human food per hectare than dairy cows and are associated with more greenhouse gas per unit of food production.
In a globally responsible world, the efficiencies of food production, and New Zealand's efficient farmers, should be part of the marketing that creates extra revenue.
The latest Situation and Outlook for the Primary Industries was launched in June at Mystery Creek National Fieldays.
The report acknowledges that the 2012 goal of doubling primary sector exports to $64 billion in real terms by 2025 is not likely to be reached as the nominal forecast for 2020 is only $44 billion.
However, what has already been achieved is an increase in value for the whole sector of over 5.5 per cent a year. The forecast is for 5.4 per cent a year overall (2013 to 2020). The big boost between 2013 and 2014 was the 18 per cent increase in export value led by dairy and forestry - from only 3.8 million hectares.
This year it is horticulture that is leading the charge - a 20 per cent increase forecast for 2016 led by kiwifruit, wine and pip fruit.
Horticulture covers approximately half a million hectares and generates $4.2 billion in export revenue.
Although conversion to horticulture might be suitable for some current dairy farms, seasonal labour is a problem, and so is disease strike.
An extra problem is that the further the horticultural activity is from the pack houses and ports, the greater the contribution to greenhouse gas emissions.
By 2020, The Ministry of Primary Industries forecasts that meat and wool will have decreased in export value by 2.2 per cent, dairy will have grown by 26 per cent, and horticulture will have increased by 37 per cent.
In these projections, change of land use is only part of the consideration, but is important in response to consumer demands and in climate change.
The point about any land-based activity is that the activity must suit the topography and climate, which interact with the parent material to create the soil. Farmers and growers understand the nature of the interaction, and then manage the deficiencies - fertilisers, irrigation, herd shelters, for instance.
They also consider the infrastructure, processors and markets. The goal is financial viability and environmental sustainability.
Debate about where New Zealand should focus in future should be at a higher level than whether or not dairy farming is taking over New Zealand.
Minister of Finance Bill English has stated that the dairy sector had pulled New Zealand out of economic recession, and it has done so from only 1.7 million hectares - only 6 per cent of New Zealand and 12 per cent of pastoral land.
Also worth remembering is that about 30 per cent of New Zealand's 26.8 million hectares is in the Department of Conservation Estate, supported by government revenue.
Although DoC has Molesworth Station (181,000ha) under its aegis, the station is managed by Landcorp with 10,000 beef cattle; and production is vital to control weeds and pests.
There are no easy answers, and unintended consequences are likely if decisions are made on the back of emotion rather than analysis.
New Zealand's beautiful countryside requires good management and in being managed productively, supports the economy.
The reality of Paul Harvey's 'and God made a farmer' is worth considering in Godzone.
- Jacqueline Rowarth is a professor of agribusiness at Waikato University.