Written by John Meadley from the Pasture Fed Livestock Association
“Humankind, despite its artistic and technical abilities, sophistication and accomplishments, owes its existence to six inches of soil – and the fact that it rains”. That phrase, attributed to Confucius (551 – 479 BC), reminds us that soil is the most basic, vital and precious medium – without which humanity could not exist. We are taught at school that the plants that live in this soil convert sunlight, through photosynthesis, into sugar. But just as man does not live by bread alone, so plants do not live by sugar alone. Much of this sugar is passed down to the roots where it is exuded out into the plant’s rhizosphere – the film of soil immediately surrounding the roots. Just as we humans are dependent upon the vibrant and complex fauna and flora in our gut (our microbiome) to digest our food, so plants are dependent upon the fauna and flora (their microbiome) in their rhizosphere to convert their photosynthesised sugars into the myriad of metabolites that they need to grow and to protect themselves. In order to thrive and engage with their microbiome, plants need a strong, healthy root system with a large surface area.
As we continue to cultivate the soil we would be wise to remember that plants and animals were able to feed, protect and reproduce themselves long before man came on the scene and that soil co-evolved – without any help from man – together with grasses, shrubs and trees, with the flora and fauna that lived around their roots and with the animals that grazed on them. What can we learn from that? Most important is to recognize that when we cultivate the soil and harvest the subsequent crop we destroy those symbiotic relationships, break up the mycorrhzal pathways, oxidise the organic matter, dry out the soil and reduce its fertility. The soil needs then to be healed. Farmers have realized this since time immemorial – recognizing the need for fallow, rotation and grazed pasture. Way back in 35BC the Roman poet Vergil wrote (translation by C Day Lewis):
See, too, that your arable lies fallow in due rotation,
And leave the idle field alone to recoup its strength;
Or else, changing the seasons, put down to yellow spelt
A field where you raised the beans with its rattling pods
Or the small-seeded vetch
Or the brittle stalk and rustling haulm of the bitter lupin.
For a field of flax burns up a field and so does an oat-crop,
And poppies drenched in oblivion burn up its energy.
Still, by rotation of crops you lighten your labour, only
Scruple not to enrich the dried-up soil with dung
And scatter filthy ashes on fields that are exhausted.
So too are the fields rested by a rotation of crops,
And unploughed land in the meanwhile promises to repay you.
Beans, Vetch and Lupins – and later he refers to Lucerne and Lentils – are all nitrogen-fixing legumes, the benefits of which they were aware almost two centuries before Linnaeus introduced the concept of botanical families – including the Leguminosae (now Fabacae). Having already recognised the importance of animal dung (….to enrich the dried up soil) later Vergil writes about grazing lush young cereals….. Another, for fear the cornstalk should wilt under the ear’s weight, Grazes down the exuberant crop while yet its young green Is barely showing above the furrows.
For centuries the concept of rotation, and the virtues of legumes, has been recognised by farmers. During the eighteenth-century Viscount Townsend (Turnip Townsend) encouraged roots and pasture within his four-course rotation – with ruminant animals as the centre-piece; sheep folded on arable crops and both sheep and cattle grazing on pasture. This fouryear rotation had two major effects on agriculture. The first was that the harvest increased in yield.
In 1705, England exported 11.5 million quarters of wheat (approx. 13,000 tons) . By 1765, wheat exports had risen to 95 million quarters (107,000 tons). The second effect was that livestock, which no longer needed to be slaughtered before the winter months, increased in both quantity and quality.
In 1891, Armstrong College (together with Cockle Park Farm) was established, later to become the Agriculture Department of Newcastle University. In 1896 it started a series of trials to improve grassland that ran for more than 60 years. Key to their success was the introduction of wild white clover (WWC), which greatly out-yielded the commercial strains of white clover then available. Together with the application of basic slag (a phosphate-rich bi-product of the steel industry) and the Cockle Park Mixture (Ryegrass, Cocksfoot, Timothy, WWC and a range of herbs) this transformed the productivity of millions of acres of pasture across the UK. Speaking at the Farmers Club 100 years ago in May 1920 , JGG Rea CBE (later to be the chair of the Northumberland War Agricultural Executive Committee) noted:
“I had some land adjoining a moor which was reclaimed by my grandfather. It was kept in cultivation almost entirely for the sake of growing roots for the sheep. We looked upon the corn crop as a necessary evil and 30 bushels an acre was considered a good crop. After an application of 1.5 lbs/acre wild white clover the grazing was what I considered phenomenal, and when the pasture was ploughed out after two years the yield was 71 bushels. Not only does WWC increase the yield, but it cleans the land to an extraordinary degree…its seems to have such a dominating effect that after a course of two seedings the land is completely free of twitch”
Have we forgotten these early lessons about the benefits of grazed, biodiverse pastures? Until around 70 years ago farmers focused on working together with nature to maintain soil fertility as well as both soil and crop health. This changed as WW2 brought pressure to produce more food and with the introduction of a range of synthesised chemical compounds. Much grassland was ploughed up to produce crops ……and also because it was no longer needed to feed horses – reflected in Harry Ferguson’s mantra that: “One third of the land cultivated by horses is used for growing their fodder”.
Although UK farmland is still two thirds pasture, there are increasing numbers of ploughed acres that not only do not enjoy the benefits of biodiverse pasture but are left as bare soil for extended periods. Nature doesn’t do bare soil – for several reasons. Firstly, Nature seeks efficiency and it is the colour green, not brown, that photosynthesises. Secondly, as is evident from this photo , soil under vegetation, particularly biodiverse, grazed pasture, builds up the organic matter in the soil which in turns builds soil structure, improves both water holding capacity (150,000 – 225,000 litres of water per 1% organic matter) and drainage and both retains and releases nutrients. Further, as is evident from any train window and from the graph below from North Wyke, bare soil washes away. Given that soil is the single most important and irreplaceable capital on a farm, allowing it to wash away is little short of giving people both your credit card and PIN number – a view influenced perhaps by spending my formative working years in southern Africa in the 1960s when installing and maintaining soil conservation measures was mandatory and soil erosion was considered a criminal offence.
Since WW2, farmers have been increasingly seduced by technologies that promise to increase both yield and income. As is evident from the continuing downside of the green revolution in India (whose short-strawed cereal varieties require fossil-fuelintensive nitrogen and large quantities of increasingly scarce supplies of irrigation water) – technology can be a mixed blessing, particularly when it results from reductionist research focused on single issues. This is most dramatically demonstrated in the graph below which shows the effect of Green Revolution technologies on farm income in Canada from the end of WW2 to 2002.
During this period various technologies were introduced – tractors, fertilisers (application increased by 20 times), herbicides, glyphosate, GPS and GMOs – but whilst gross farm income increased, net farm income decreased – the balance going to those who made and supplied the technology and to those who marketed the increased volumes of harvested produce. Further, in order to achieve this negative outcome, the farmers became more dependent upon the bank manager to finance their inputs whilst making less use of the freely-offered benefits of Nature. To take just one example – Nitrogen. Giving bagged nitrogen to a plant is like giving a bar of chocolate to a child. It gives a sugar rush that can make us lazy in seeking a balanced diet. The nitrogen-high plant generally has smaller roots that reduce its ability to seek out micronutrients from the soil and to withstand drought. This is bizarre when nature provides us with so much without charge – as is evident in this figure.
Mankind in general, and farmers in particular, are totally dependent upon soil. It is still the world’s single largest terrestrial store of carbon. Depending upon soil type and how it has been farmed, <70% of its carbon has been lost through cultivation since the industrial revolution, offering the opportunity for that lost carbon to be reabsorbed. It behoves us to manage this precious soil, and the life within it, as if it were our own children – life which is reflected in the soil’s organic matter…….lost when cultivated and increased when covered by vegetation for extended periods of time. Cover crops are a great step forward, preventing the soil from lying naked and exposed to both the drying rays of the sun and the damaging impact of rain. But when that vegetation is biodiverse pasture grazed by ruminants then the pasture becomes a pump that sucks the carbon into the soil – with all the benefits that this brings.
That many farmers have moved away from keeping ruminant livestock is in part due to the animals’ need for 365 day attention and the need to specialise in order to survive in a world of cheap food; but it may also reflect livestock becoming increasingly the target for much public opprobrium – accused of being a major cause of climate change. That perception is beginning to change. This is in part due to the changing understanding of methane and because the oft-quoted Livestock’s Long Shadow has been increasingly discredited .
Recent work on nutrient density at Rothamsted and elsewhere has shown that beef and lamb are significantly more nutrient dense and bioavailable than most plant foods. And further that meat produced from ruminants raised wholly on pasture is likely to be more nutrient dense than that raised on grain, and in many cases carbon positive. Whilst that may not yet be reflected in consistently higher prices for wholly pasture-fed meat, it will not be long before consumers will have access to hand-held meters that can instantly assess the nutrient density of the foods that they are purchasing in store . This will disrupt and transform the way in which farm produce is assessed and priced and should significantly increase the recognition of the benefits of wholly pasture-fed produce.
Technology has provided many products (both mechanical and chemical) and services (the capacity to communicate, record, analyse and plan). Seduced by the products of technology, we seem to have forgotten so much of the innate knowledge that farmers had a century ago when nurturing nature was the only option. In this increasingly uncertain world, we have the opportunity to relearn that historic knowledge using the best that technology offers us whilst bringing back the “muck and magic” and the “golden hoof” of ruminant livestock that can enrich the soil – courtesy of nature.
A couple of years ago I was at an event with the late Peter Melchett, then the Policy Director of the Soil Association. In response to a question about his farm, he replied: “I may be a vegetarian, but I could not farm my land in Norfolk without livestock?” I sense that, as we move forward in an increasingly uncertain world and with an increasing focus on public payments for public goods, we will begin to make a shift back towards farming being more of a conversation with nature in which biodiverse pasture grazed by ruminants plays a vital role.