with Robin Boom
Agronomic Advisory Services
December’s issue of The New Zealand Institute of Agricultural and Horticultural Science (NZIAHS) magazine, AgScience, is solely dedicated to the subject of Regenerative Agriculture.
It comprises articles by 14 senior New Zealand agricultural scientists and professors, each addressing their concerns about Regenerative Agriculture from their respective fields of expertise.
In his opening foreword, the current president of the NZIAHS Professor Jon Hickford from Lincoln University wrote: “’the cycle of life creates its own fertiliser’ is one such statement creating confusion. It sounds attractive, but it is biological, chemical and physical nonsense.
“Farming and politics are abuzz with discussions about ‘regenerative agriculture’. There are loud proponents for it in the farming community and politicians are bandying the words around.
“It is a cornerstone of the Green Party’s agricultural policy, and taxpayer money has already been directed towards its advocates.”
Professor Hickford rightly asks for the peer-reviewed science behind all of the claims and advocacy of RA, saying “science demands these things because science is driven by the quest for knowledge and understanding….it relies on repetition and critical analysis, and scrutiny via peer review and assessment.
“Science is not something you can choose to believe in, because it is something that is true whether or not you believe in it.”
In an article discussing Regenerative Agriculture’s history in NZ, Lincoln University agronomy senior lecturer Dr Warwick Scott and NZ Institute for Plant and Food Research general manager of science Dr Derek Wilson, write: “Regenerative Agriculture is a philosophy that has the improvement of ‘soil health’ as its central focus.
“RA originated in the United States in response to soils becoming damaged by inappropriate land uses, notably exhaustive cropping in unsuitable conditions with little or no livestock farming.
“Recent advocacy of RA in this country is based on the presumption that our agricultural systems are degenerated. They are not and the current claims that RA is needed to rescue them are misplaced.
“New Zealand’s world-class agriculture is based on a history of high quality science that underpins the integrity, sustainability, productivity, and economic success of its farming systems… Many aspects of RA echo current best management practices in NZ’s agriculture.”
They caution that ‘there is no evidence to support some of the more radical practices of RA, such as the recommendation to sow pasture seed mixes containing up to 60 different species.
“Arguably the biggest benefit from this could be to those who promote the sales of these seed mixes.
“Among these marketers, scientific literacy and technical knowledge of agricultural production systems appear to be absent.’
This is something I have commonly observed in the ‘alternative’ fertiliser industry the past three decades, where fantastic claims are made with no science to back the claims made by people who are scientifically illiterate and who never darken the doorways of reputable scientific institution conferences and workshops such as the NZ Grassland Association, or the NZ Society of Soil Science or the FLRC Workshops at Massey University.
Drs Scott and Wilson conclude: ‘RA is an ideology, and history shows that most ideologies have self-serving extremists. Their ideas should be subjected to scrutiny and, if appropriate, debunked.’
Food is fabricated soil fertility
From my own assessment of RA in relation to pastoral production, I think that increased pasture species diversity may have a place in certain situations.
Ryegrass and white clover have been the main species used in New Zealand because of their resilience and adaptability to our short rotational grazing system where ME and protein are deemed important productivity factors.
Plantain, chickory and red clover have proven successful alternative species in many situations, and for South Island dryland farming, grazing lucerne cultivars have been a game-changer.
However long rotations will not suit dairy cows in peak production or fattening lambs.
For kikuyu based pastures in Northland and the Coromandel, letting kikuyu get out of control can reduce its feed value to little better than cardboard or rope.
Soil biology does not make nutrients out of thin air, as plants take up chemicals, or as Dr William Albrecht once stated: “Food is fabricated soil fertility”.
That said, I think that on the moisture stressed soils of places like Otago, focussing on building soil organic matter through longer rotations of diverse species and hoofing the thatch into the soil surface has a place.