Comment: You can't accuse New Zealand farmers of "green-washing" - they have the evidence to back up their environmental performance, writes Dr Jacqueline Rowarth.
Regenerative agriculture consultants have accused farmers of "green-washing". The implication is that the farmers are making claims that don't reflect reality.
The irony is that New Zealand farmers do have the measurements to support statements about high environmental performance; which is in considerable contrast to the data-bereft blogs and websites suggesting a "better" way through regenerative agriculture.
(Note percentages are sometimes presented, but unless the starting point and the norm for the district are known, percentages are meaningless.)
New Zealand farm measurements include soil organic matter, greenhouse gases and nitrogen loss. They indicate better environmental performance than most other countries are achieving.
New Zealand scientists have done the research that has created a system that farmers from all over the world now study by webinar. From soil through to technological solutions, New Zealand farmers provide a model for others.
Soil organic matter, and all the organisms it supports, is a case in point.
Regenerative agriculture focuses on building organic matter in soils which have been depleted – by over-grazing in South Africa, for instance, or over-cropping in the American Dust Bowl.
The main technique in building the organic matter is managing grazing animals, either to prevent over-grazing (as in South Africa) or bringing them in to a cropping farm (as in the Dust Bowl).
Other aspects have been added to the regenerative concept, such as minimising use of synthetic chemicals, sowing mixed pastures, minimising soil disturbance and maintaining soil cover through cover crops or lax (high) grazing.
In these aspects, and the focus on soil organic matter, regenerative agriculture is like the organic approach, but without the regulations.
Soil organic matter in New Zealand is, on average, two to three times that in America or Australia. It holds moisture and nutrients and managing it is a skill.
The weight of soil organisms that the organic matter support is in response to the amount of vegetation grown: more pasture above-ground equals more biomass underground.
That's because the pasture is food for the agricultural animals as well as the soil bugs.
The equilibrium in above-ground production and soil organic matter reflects temperature and rainfall (and irrigation in some areas), as well as inputs such as fertiliser and grazing management.
Listen to Jamie Mackay interview Dr Jacqueline Rowarth about "green-washing" on The Country below:
Altering the balance could have unintended consequences.
Reducing fertiliser inputs will lead to a decrease in organic matter. Allowing pasture to grow longer than is currently usual before grazing will decrease pasture quality.
This will increase greenhouse gases (GHG) per unit of production.
It will also require a decrease in stocking rate, and the combination means a decrease in production. This is apparent from many comparisons of conventional and organic production systems globally.
Contrary to ongoing assertions, decreased production will have a detrimental effect on income, unless a premium can be achieved.
Economic analysis of Australian research comparing conventional and regenerative dryland sheep farming over a decade indicated a shortfall of A$2.47 million dollars with regenerative agriculture and a return on assets managed of 1.22 per cent in comparison with 4.66 per cent for conventional sheep farming.
Testing "willingness to pay" is part of the latest Ministry for Primary Industries investment through the meat and wine industries. But the clue already exists in organic production – most people don't pay the extra.
A further complication is that regenerative agriculture is not supported by regulation; why would people pay extra for something that might be "green-washing"?
This has led to suggestions that New Zealand should simply move to organic production systems. But in its June insight, LEK Consulting pointed out that despite mainstream support and significant growth in the last couple of decades, less than 1 per cent of US farmland is certified organic.
Dr Jacqueline Rowarth. Photo / Supplied
The problem continues to be price.
In addition, there is increasing recognition that there is an environmental cost for organic production systems.
Research published at the end of last year evaluating the GHG impacts of converting England and Wales to organic production systems suggested that the result would be increased GHG emissions from necessary land use changes.
The authors concluded that it is ultimately unlikely that any single optimal approach to achieving environmentally sustainable food production exists: context-specific evaluations are required.
Applying this to the New Zealand context reveals that farmers are doing pretty well.
In particular, most soils appear to have soil organic matter that is near capacity. This means that attempts to increase it further will be both expensive and likely to have little effect.
The point is that when there is a lot of soil organism activity, breakdown of any plant material is rapid. A further complication is that as the climate becomes warmer and drier, organic matter disappears more rapidly than it is replaced (think deserts. This is likely to be a significant issue for the East Coast of New Zealand.
It is understandable that Regenerative Agriculture Consultants want New Zealand farmers to do better – but they don't know the farms in the same way that farmers do, and context matters.
In this, the farmers have the most to gain, or lose, and with livelihoods at stake, they are the ones that want to do better more than anybody else.
• Dr Jacqueline Rowarth is a soil scientist and a farmer-elected director for DairyNZ and Ravensdown. The analysis and conclusions are her own. jsrowarth@gmail.com
