22 November 2013
Mob grazing is a school of ‘natural farming’ that seeks to mimic the movements of grazing plains animals on a farm scale. The approach is receiving attention around the world, thanks to pioneers who have put remarkable achievements down to mob grazing, and their claims that it can be used to replenish soils exhausted by monocropping or boost the health of pastureland.
In essence, mob grazing involves grazing cattle at high density, in a smaller area than conventional pastures, and in short duration grazing periods. In North America, where the technique has been developed and refined, this can mean 1,000 cattle grazing one acre and being moved every few hours using electric fences. Influential adherents claim that, through mob grazing, farmers can attain the “holy grail” of good liveweight gains, healthy cattle, rapidly increasing soil organic matter, longer grazing periods and more resilient farm systems.
It works on the premise that modern management practices – hungry for inputs and reliant on large amounts of fossil fuels – are in fact bad for the long term productivity of grasslands. Grazing animals and meadows have evolved in tandem, with each shaping the other. Mob graziers believe that this relationship has become unbalanced under the current agricultural paradigm.
The practice was developed by Allan Savory, a Zimbabwean naturalist and farmer, who, in attempting to revive damaged grasslands, observed that, by replicating natural interactions between animals and their environment, he could ensure that both remained in good health.
How mob grazing works
Under mob grazed management, cattle are put to pasture in high numbers and a relatively small space, where they eat grasses grown tall (alongside clovers and other plant types in polyculture systems), having been allowed adequate time to recover and complete their full lifecycle. Cattle eat the most nutritious part of the plants and trample the rest into the ground, leaving a grass ‘mat’. This mat forms a protective barrier for the soil. When it is broken down this returns nutrients and enables ‘friendly’ soil bacteria and worms to flourish while new grass grows through the cover.
The mat also prevents soil from drying out in the heat, helps form an extra layer of organic matter, which can absorb more water during periods of heavy rainfall and protect soil from cattle poaching, enabling pastures to handle the higher stocking densities used to replicate large travelling herds.
A bit of context
Soil experts have warned that UK soils require urgent restorative action. The last national soils review (conducted in 2009) revealed that the country is losing two million tonnes of topsoil each year to erosion. Earlier this year, scientists at the University of Sheffield cautioned that, unless soil health becomes a top priority, there may only be 100 seasons of comparatively healthy soil left in the UK.
The EU soils directive, which has been stalled at the draft stage for several years, recognises the importance of soil and would, if passed, classify the resource as non-renewable, given the amount of time and energy it takes to rebuild the complex relationships needed for healthy soil (key elements of which are only now beginning to be understood by scientists).
Fortunately, according to Tom Chapman, a Hertfordshire farm manager and Nuffield Scholar, who has visited farmers in North and South America over the past two years to explore mob grazing in areas where it is better established, attitudes appear to be changing and scientists’ warnings are finally being heeded. He said, “There’s a groundswell of people taking an interest in soils and the biology behind… ‘healthy’ soils. Previously many farmers, myself included, have believed that nutrients can be balanced using artificial fertilisers. This is true to a degree, but at a cost – that cost being a loss of soil through erosion, a loss of Soil organic matter (SOM) [and] hardening of the soil.”
Advantages of mob grazing
In the Americas, from Argentina, to the plains of the Dakotas and up into Saskatchewan, Canada, mob grazing has been shown to improve soil health, enable farmers in a diverse range of climates to winter their cattle outside, or at least extend the grazing season and make more feed available through allowing pastures to recover for longer periods. Pastures can grow to up to 4 feet in the UK, according to Tom, and when plants are not stressed they put out more leaves, capturing more energy, rather than going immediately to seed as received wisdom would imply.
Tom, who studied the approach‘s potential for use as a break to replenish exhausted croplands, discovered great potential for keeping cattle within an arable rotation to build fertility, control weeds and contribute to the resilience of the farming business. He believes management techniques such as mob grazing, which replenish soil health, are reasons why “for hundreds of years, UK farms were mixed farms.”
Speaking to Farming Online in November, he elaborated on the approach, “The overarching aim of mob grazing is to improve UK soils. It’s one tool in the toolbox that allows us to do this – and by improve them I mean increasing the organic matter (SOM) providing a habitat and environment in which the SOM can be broken down by the microbes, organisms and fungi etc that live in the soil.
“There are other ways to achieve some or all of this – direct drilling, cover crops, composts, FYM application etc, but where [mob grazing] ‘wins’ over many of the alternatives is that you get some income from the practice and improve soils at the same time. Composts, cover crops etc are a cost – purchase, application, etc – though all will reduce input costs in the longer run so shouldn’t be dismissed.”
Tom added that the success of the technique revolves around finding optimal stocking rates and timing cattle movements well during the growing season, to ensure adequate regrowth time for grasses before cattle return and also to create a surplus of grass around the farm, which can then be used as fodder when the season ends. As plants can have upto 100 days to recover after grazing, their roots run deeper, bringing up nutrients and water from further down in the soil, and, just prior to grazing, putting up seedheads which are nutritious for cattle. Due to the fact that mob grazing builds up grass at high rates, in an environment such as the UK’s, cattle would have to be stocked quite densely to ensure adequate grazing, and prevent weeds from taking over during rest periods.
Mainstreaming mob grazing
Tom believes that the approach he studied – mob grazing cattle as part of an arable rotation – could be widely adopted to provide opportunities for new entrants. He believes young people could take on areas of arable farms, working within a much longer rotation that introduces of mob grazed herds as an arable break. Under this scheme, entrants would take on a portion of an arable farm for three years to restore the soil health while the arable farmer moves their rotation around the farm. This, he said, would provide the farmer with access to free soil restoration, as well as some extra income, and the new entrant with access to land.
Speaking at last year’s Nuffield Conference, Tom admitted that he “dream[s] of seeing East Anglia covered in grazing livestock.” Earlier this month, he said, “This makes enormous sense. At the moment we have quite an unbalanced industry – much of the feed and bedding for animals is grown in the east whereas much of the fertility that is needed to grow these crops is produced in the west.
“A rebalancing – a movement of animal production from west to east – would address this issue. The end result would be that crops would be cheaper to grow, whilst livestock would also be cheaper to produce.”
However, he added that there are currently barriers to ‘mainstreaming’. Tom said, “I do feel one of the weaknesses of our research system is that there is very little government funding. Most projects, it seems to me, are backed by businesses who have a vested interest in looking at particular systems and ignoring others.
“If a scientist says he or she wants to look at ways to reduce or cut out the use of fertiliser [or] sprays, no inputs business is going to want to fund that – they can’t see a way to make money from the results. It’s left to [small players] or individual farmers to carry out their own, small scale trials.”
Nevertheless, he said that he remains a resolute optimist and pointed out that, through improvements in communication, “farmers are [now] able to share real-time and real-world results with other farmers around the globe.”
Calling for a reassessment of research funding allocations in Parliament last month, ‘agroecology‘ experts from the Centre for Food Security and Agroecology at Coventry University called for better targeted government funding to ensure research benefits the end users, society and the environment – which are all too often sidelined in the profit-oriented research ‘industry’. They also commended the work of independent networks of farmers, such as BASE in France, who are gathering and sharing information on successful sustainable farming methods, acting on their own initiative.
Nuffield scholars discuss the potential for UK grazing
David Hugill, a pioneering Nuffield scholar farming within the North York Moors National Park, said some advantages of mob grazing are already being realised and aspects of the approach are gradually being incorporated into UK farming. He told Farming Online, “The potential is [there] for at least some of the theories of MG to go mainstream. We are starting to see this i.e. rest and recovery, smaller paddocks, more moves, more focus on soil organic matter, more species rich grassland.” Hugill agrees with Tom Chapman that mob grazing, used as part of an arable rotation holds perhaps the greatest potential for bringing mob grazing into the mainstream.
However, he said that, in order for this to happen, there needs to be a marked shift in attitudes, research and potentially farmers’ goals. He concurred that “The current research agenda does not support [mob grazing]” and added that he had “been involved in plenty of failed bids” for projects. He added, “Mob Grazing is part of holistic management (HM). A farmer can’t hope to Mob Graze successfully if his or her goals don’t fit with the main reasons for HM – to reduce inputs, improve lifestyle and create a more biologically active soil.”
Whilst both Chapman and Hugill are convinced of the great potential for mob grazing, especially the idea of allowing new entrants to graze cattle cover crops on depleted soils in the Eastern Counties, Mr Hugill said the conditions are not currently in place and a “skills cap prevents management of [mob grazed] cattle” in these areas. Nevertheless, he added that he “Would love to be part of a project to manage this.”
Responding to a parliamentary question in 2010, former Defra secretary Jim Fitzpatrick said that scientific evidence suggests mob grazing would not be suitable for large areas of the UK, citing the potential for pollution and soil compaction.
Unlike North America or large parts of Europe, Britain’s only large grazing animals were the aurochs (the wild descendent of modern domestic cattle, which eventually became extinct in the 1600s). The aurochs are thought to have last lived in Britain 4,000 years ago and wisents, Europe’s other large wild grazers, never reached these shores.
Nevertheless, Tom Chapman maintains that our grasslands, like those in other areas where mob grazing has taken off, evolved in tandem with wild grazing animals over a much longer period, the UK must be suitable. He went further, “The UK has soil, the soil needs feeding, mob grazing achieves this, therefore it’s suitable… That’s the glib answer.”
Tom added that lower fossil fuel use, better drought tolerance and better water carrying capacity from mob grazing are also evidence, not only of its suitability for the UK, but its necessity. Considering the forecasts for more erratic rainfall and the effects of peak oil (fuel prices are already increasing and governments and corporations are turning to increasingly damaging and inefficient means of mining fossil fuels), he may have a point.
Commenting on the conditions he believes need to be in place for a wider acceptance of ‘natural approaches’ like mob grazing, Mr Chapman added, “A lot of the ‘new’ learning is counterintuitive when compared to what we’ve been taught previously. It is only by educating people about their soils that we will be able to ‘sell’ the principles of mob grazing to them. Interestingly, the majority of arable farmers who have started direct drilling ‘get’ the principle as they have started to realise that soil is a living material; likewise organic farmers ‘get it’ too, for the same reasons.”
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