Green Martinstown Talk: Will Streatfeild on Sustainability in Food and Farming
We are enormously grateful to Will Streatfeild, (Commercial Sustainability Head at Alltech) for giving freely of his time to speak to us on Friday night at our annual supper evening. It was wonderful to listen to him speaking about the realities of sustainability in agriculture, drawing on his own background growing up on a mixed dairy-and-pig farm, and later managing dairy herds in the UK and New Zealand. Will brought both science and lived experience to a subject often discussed in headlines rather than in context.
No Single “Silver Bullet”
Will opened by stressing that there is no one-size-fits-all answer to sustainability. Every choice made in farming and food production has both benefits and repercussions. We must endeavour to understand those trade-offs clearly rather than chase overly simple solutions. Agriculture contributes to global greenhouse-gas emissions, but it also sits on the front line of their impact: droughts, reduced yields and increasing volatility.
Beyond “Carbon Tunnel Vision”
Carbon has become the main focus of sustainability debates, largely because it is relatively easy to measure. Will reminded us that carbon is only one metric among many. True sustainability also depends on soil health, biodiversity, water quality, air quality, social equity and education. These are harder to quantify but just as vital. Focusing only on carbon, he said, risks ignoring complex interconnections and repeating mistakes of the past.
The Soya Story: A Case Study in Complexity
One of Will’s most eye-opening examples was the case of soya cultivation. On the one hand, soya is remarkably efficient: it fixes nitrogen naturally, reducing the need for fertilisers, and provides an exceptional yield of protein and energy per hectare. Yet this apparent success story has a darker side.
In 2022, an area of Brazilian forest equivalent to 40 % of Wales was lost to soya production (around 90 % of it illegal deforestation).
However, Will challenged simplistic blame narratives. The deforestation is driven by global economic demand, not by the crop itself. If it weren’t soya, it would be another crop—perhaps even more damaging. He also reminded us of the hypocrisy of wealthy nations condemning Brazilian farmers while having deforested our own landscapes centuries ago. The challenge is global: to pay fairly for sustainable production and to recognise the human face of those driven to clear land simply to feed their families.
Land Use and Livestock
Will also tackled the often-polarised debate around meat and dairy. Around a third of methane emissions come from the dairy industry, but removing dairy cows entirely from the UK landscape, he argued, would create unintended environmental consequences. Much of our pastureland simply cannot grow crops for direct human consumption, so grazing animals can make use of land that would otherwise produce nothing edible. Livestock also upcycle waste products such as by-products from brewing and baking—turning what might become landfill methane into high-quality protein.
Measuring True Progress
Sustainability in agriculture, Will explained, isn’t just about cutting emissions but about improving efficiency and resilience. He outlined three broad strategies:
• Maximise efficiency – producing more food from the same inputs through better management, genetics and technology.
• Reduce the carbon intensity of inputs – such as greener fertilisers or methane-reducing feed additives.
• Sequestration and insetting – restoring soils, planting trees, and capturing carbon within supply chains rather than outsourcing it through carbon credits.
He praised major food companies—including, surprisingly to many of us, McDonald’s—for investing heavily in genuine sustainability work with their farmers. These initiatives, from improving soil biodiversity to paying for lower-impact production, aren’t just good PR: they’re about ensuring long-term food security and resilience.
A Cautionary Tale from History
To end, Will offered a stark historical lesson. During China’s “Four Pests Campaign” under Chairman Mao, citizens were urged to exterminate sparrows, believed to eat valuable grain. The campaign succeeded… but without sparrows, locust populations exploded, destroying crops and contributing to one of the worst famines in human history, with tens of millions of deaths. The moral: when we fail to understand the full web of nature, well-intentioned policies can have disastrous consequences.
Reflection
Will’s talk was both sobering and hopeful. It was an invitation to think critically about the food we buy, the systems that produce it, and the ripple effects of our choices. Sustainability, he reminded us, isn’t about perfection or purity, but about balance, knowledge and empathy—seeing the bigger picture, from soil microbes to supply chains.
