Regenerative agriculture is in vogue as a concept but what does it really mean?
I often get asked my opinion about regenerative agriculture. My standard rejoinder is to ask what does the questioner mean by ‘regenerative agriculture’? That typically gets a response that it is somewhat of a mystery to them, but it is a term they keep hearing, and supposedly it is the way we need to act to save the planet. My next rejoinder is that I too am struggling to know what it means.
Then some two weeks ago I was asked to join a focus group for a research project looking into what regenerative agriculture means specifically in the New Zealand context. The project has considerable backing, including from the Government-funded ‘Our Land & Water National Science Challenge’.
I was unable to participate in the focus group on account of another commitment. But it did make me think it was time for me to do my own research and find out what the term actually stood for.
Some ferreting around led me to a paper by Dr Charles Merfield, widely known as ‘Merf’, who is well known in organic agriculture and sustainable farming circles in New Zealand and beyond. I thought if anyone knows what it means then it will be Merf.
I quickly found that Merf has also found it challenging to get a clear definition of regenerative agriculture. Aha, I said, so it is not only me who is struggling.
Merf quoted from a paper published by Terra Genesis International (TGA), who are promoting the concept. The TGA paper says at the outset “that Regenerative Agriculture cannot be defined.” Apparently, this is because regenerative agriculture is an evolving concept and it is expected that it will continue to evolve.
Both from Merf’s paper and the TTGA paper I quickly learned that, in contrast to organic agriculture which has prescribed rules, regenerative agriculture has no specific rules. That is why it can mean different things to different people. However, one point of agreement seems to be that ‘regenerative agriculture’ goes beyond ‘sustainable agriculture’ in setting a higher bar.
I then went to Wikipedia to see what it had to say. One has to be cautious with Wikipedia on matters that are still evolving, but at least it would provide a perspective.
Wikipedia said that regenerative agriculture “is a conservation and rehabilitation approach to food and farming systems. It focuses on topsoil regeneration, increasing biodiversity, improving the water cycle, enhancing biodiversity, enhancing ecosystem services, increasing resilience to climate change, and strengthening the health and vitality of farm soil.”
Some further ferreting around led me to the conclusion that regenerative agriculture is really a value system largely coming from the USA and then spreading out from there. It is built on a belief that says that we are depleting our soils and we need to do a lot better.
Then it was back to Merf’s paper to see what he had to say about the underlying science. To my initial surprise, Merf said that there was minimal peer-reviewed literature on the topic. His own search using the combined terms ‘regenerative’ and ‘agriculture’ only found two such papers in science journals, whereas a search using the terms ‘resilient’ and ‘agriculture’ produced many thousands.
Instead, almost all of the literature on regenerative farming is in what is called the ‘grey literature’ of reports that are not peer reviewed and also articles in popular non-scientific magazines. Nevertheless, there are some principles that are generally agreed to.
The four most commonly agreed principles according to Merf are:
- minimising or eliminating tillage (through no-till);
- avoiding bare soil / keeping the soil covered at all times with living plants or residues;
- increasing plant biodiversity (both pasture and crops); and
- integrating livestock and cropping (mixed /rotational farming).
Another key insight is that many of the promoters of regenerative agriculture do not themselves have a background in science. This makes it particularly challenging to link the value systems to explicit practices that align with the beliefs.
By now I was aware that at least some of the principles of this regenerative agriculture movement have been around for a long time, including back in the 1960s at Lincoln University when I was a student. For example, Professor Walker never allowed us to forget the fundamental importance of clover within the nitrogen cycle on our pastoral lands. Similarly, all of the cropping rotations that we were taught by Jim White, Bruce Ryde and others had an animal phase within them.
Back in those distant times we had neither the tillage machinery nor the weedicides, in particular glyphosate, that would make no-till systems feasible. However, those systems are now very much part of mainstream agriculture. Glyphosate is currently acceptable to most followers of regenerative agriculture as the lesser evil relative to alternatives.
As for plant diversity, that was always a key part of New Zealand’s pastoral systems until around 20 years ago when it became evident that on dairy farms the combination of ryegrass and nitrogen fertiliser was the way to maximise profits. Currently, there is a modest movement back towards more plant diversity using species such as plantain, although it is not all straight sailing.
Searching a little further, I found that use of compost is another favoured technique for regenerative farming, including importing compost from outside the farm. There is no doubt that compost contains valuable nutrients and can help to increase organic matter in soils. The challenge is that, at regional and national scale, importing compost is not really feasible. Where would it come from?
This leads us back to one of the fundamental aspects of nutrient cycling that underpins sustainable farming systems. Unless human excrement is returned to farms then there will always be a need for non-organic fertilisers.
Clover and other legume species can fix nitrogen from the air with the help of nitrogen-fixing bacteria. Other plants can then obtain necessary nitrogen from the nitrogen released by these crops into the soil, although growth is typically less than achieved with fertiliser nitrogen. As for phosphorus, sulphur, potassium and micro nutrients, they have to come from somewhere else, and that means fertiliser.
Digging deeper again, I find that many of the current mainstream scientists are highly frustrated by the regenerative agriculture movement. They find it exasperating to have to deal with people who have political sway but have no understanding of fundamental scientific principles. Indeed, they find it insulting. And so, the scene is set for tribal shouting matches.
So, where do we go from here?
The answer has to be that an ongoing move to higher levels of sustainability has to be supported. We do still have farming practices, particularly in the dairy industry, that are non-sustainable. However, the other side also needs to learn some science and understand something of what is already being achieved and the nature of the constraints.
Ironically, although I would not consider myself part of the regenerative agriculture movement, I do have an involvement with a transformational pasture-based dairy system through incorporation of ‘composting moo-tels’. Dairy systems with composting moo-tels fit very nicely within the regenerative philosophy. It is an example of how we can bring sustainability, cow welfare, human welfare and economics together within a scientific framework. The first step is to get everyone to understand what we are talking about and to dispel uninformed perspectives on both sides that are getting in the way.