Soils ain’t soils

Andre Leu spoke in depth about the importance of soil organic matter in his recent presentation.182482 Pictures: RUSSELL BENNETT
The world-renowned Andre Leu gave a fascinating insight recently in his presentation on regenerative agriculture to a group of local farmers at Hallora. The Gazette’s RUSSELL BENNETT headed along to soak in as much as he could about, among a range of topics, where most farming starts – the soil…

 

A guest of the Baw Baw Food Movement, Andre Leu’s presentation late last week on regenerative agriculture broke down just what it is for farming to be ‘sustainable’ or ‘organic’, and explored how to regenerate the environment in which agricultural farming takes place.

An internationally-recognised speaker and the author of ‘The Myths of Safe Pesticides’, Andre is also a past president of IFOAM – the International Federation of Organic Agriculture Movements – and was the first Australian to hold that position.

He has over 40 years’ experience in all facets of organic agriculture, including growing, pest control, weed management, post-harvest transport, new crops and education – not just in Australia, but right across Asia, Europe, America, and Africa.

He’s written for, and been published extensively in magazines, newspapers, and journals – both in print and online – in the many areas of organic agriculture, including climate change, the environment, and the health benefits of organic agronomy.

But more than that – he runs an organic tropical fruit orchard in Queensland’s Daintree.

Andre is also an international director of Regeneration International, an organisation that promotes food, farming and land use systems that regenerate and stabilise climate systems, the health of the planet and its people, communities, culture, and local economies.

As he says, regeneration is farm more than simply just being ‘sustainable’.

“Sustainable is defined as keeping the present system stable without degrading or running it down,” he said.

“Regeneration improves the current systems.

“Do we want to sustain the current status quo, or do we want to improve it?”

Andre discussed the broader concept of Regenerative Agriculture, which was started by Robert Rodale in the 1970s and stemmed from the organic sector.

“Regenerative organic agriculture improves the resources it uses, rather than destroying or depleting them,” Andre’s presentation, which referred directly to Robert Rodale, stated.

“It is a holistic systems approach to agriculture that encourages continual on-farm innovation for environmental, social, economic, and spiritual wellbeing.”

As Andre discussed, “regenerative agriculture is now being used as a term for the many farming systems that use techniques such as longer rotations, cover crops, green manures, legumes, compost, organic fertilisers, organic agriculture, agroforestry, agroecology, permaculture, holistic grazing, intensively time-managed grazing systems, and other agricultural systems that can increase soil organic carbon.”

Throughout last week’s presentation, one thing that became abundantly clear is that the soil ecosystems and soil biology has often been overlooked in the way in which agriculture has been examined throughout the generations.

“One of my greatest moments in life was December 5, 2014 – (the first) World Soil Day,” Andre said.

“We were invited to New York, to the United Nations, and we launched not just the International Day of Soil but 2015 as the International Year of Soil. That, to me, was a paradigm shift and a game-changer globally.”

In talking about his role with Regeneration International, Andre spoke about looking beyond the concept of sustainable farming.

“What we’re trying to get across with this word ‘regenerative’ is that we want to be far more than sustainable,” he said.

“Sustainable is a buzzword that’s actually over-used in agriculture. Everything is sustainable now.

“I’m not trying to be negative – I think it’s a really important thing that we do try and be sustainable, but by definition it means keeping the status quo without further degrading.

“The better thing is to improve it. Regeneration is about improving – making things better.”

Andre also spoke specifically about the significance of ‘soil organic matter’ and what it increasing it means to a farm’s water-holding ability – particularly when it comes to capturing and storing water in unreliable rainfall times.

“Organic matter management is the primary tool in organic farming,” he said.

“Plant residues from compost, green manures and the like contain all the nutrients crops need. This is because they contain all the nutrients used by the original plant sources.

“However, organic matter provides many more benefits than just biodegrading to release nutrients to plants. Organic matter is more than just a fertiliser.”

Andre showed two examples of corn crops from a 1992 peer-reviewed study – involving the same soil, and the same variety of corn during a drought.

One was managed by an agricultural university in Pennsylvania, and the other by a committee of local organic farmers utilising best practise.

“The organic corn doesn’t know it’s a drought because it’s built up the soil organic matter, and it’s stored all that extra water and can use it,” Andre explained, adding that another peer review, this time from Cornell University, found that in drought years, systems with a good level of organic matter can get around a 30 per cent higher yield.

“Looking at these systems over a decade as the climate cycles, what they found is that systems with high amounts of organic matter – when the bad years came – didn’t drop much.

“Think about it more than just a fertilizer – it has multiple benefits. I actually prefer to use the term ‘crop nutrients’.”

Andre spoke about organic matter management being the primary tool in regenerative farming.

“Plants are primarily composed of cellulose and lignins,” he explained in his presentation.

“Cellulose biodegrades into glucose that feeds the microbes of the soil food web.

“These microbes break down cellulose and other plant residues, releasing nutrients for the crop.

“The soil microbes have many other functions, such as building good soil structure, unlocking minerals and protecting plants from disease.”

Andre said that organic matter stores both anions, and cations. He said that anions contain 90 to 95 per cent of the nitrogen, 15 to 80 per cent of the phosphorous, and 20 to 50 per cent of the sulphur in the soil.

The cations include the likes of calcium, magnesium, potassium, and all trace elements.

“Organic matter promotes high levels of beneficial micro-organisms to ensure a healthy soil biology to protect plants and assist with nutrient availability,” he surmised.