Conservationists tell us about the extinction of wildlife, but there is another more insidious extinction going on right now – the disappearance of traditional dairy farmers, who have supplied our nation’s milk for generations. As each demoralised farmer quietly gives up and goes out of milk – and there are nearly two a day being forced out right now – a precious and irreplaceable part of our national heritage is lost forever. The Prince of Wales is absolutely right to be highlighting the plight of small family farms in general and dairy farms in particular.

These farmers form the backbone of the rural economy. By their very existence, they play a crucial role in maintaining our countryside. They are the stewards of our landscapes, field boundaries and hedgerows, the guardians of the fertility of the soils, the pastures, biodiversity and the ancient green lanes for herding the cattle in to be milked. As each farm disappears, the skills of the stockmen are also lost and will be difficult or impossible to replace. These are all priceless elements of our natural and cultural capital.

The reason I feel particularly passionate about this is because I am a dairy farmer myself. I was milking my dairy herd of 80 cows in West Wales on Thursday afternoon when I got a call asking me to write this piece. I am in a lucky position compared with most milk producers, since although we have been receiving less than the cost of production for our milk for a number of years, we have managed to stay in business, partly because we benefit from a modest premium for being organic and also because we are now adding value to our milk by making cheese. I also have a day job, the salary from which goes to shore up any losses.

However, for the majority of UK family dairy farmers, who do not enjoy these privileges, the relentless decline in milk prices has finally driven them into taking direct action, albeit in a less militant fashion than their French counterparts. In doing so, they may not realise that, ironically, they are up against a deeply entrenched orthodoxy in British food and farming circles, shared even by those who claim to represent them. The orthodoxy goes something like this: in an industrial age where reductionist science and global markets rule, we must accept that in farming and food production, as with every other industry, we will be at the mercy of global trade, fluctuating market prices and cycles of boom and bust.

In this brave new world, only the fittest will survive; British dairy farmers must adapt by becoming ever more efficient and becoming larger and more intensive in order to survive in a competitive global market. The impressive list of individuals and organisations that sign up to this orthodoxy includes the prime minister, the secretary of state for agriculture, the president of the National Farmers’ Union and the bosses of most large food retailers. If pressed to comment on this cultural cleansing by price of a whole industry, they will wring their hands and say how sad it is, but admit there is not much they can do about it. Well, that may be true, but only so long as you subscribe to the mantra of unfettered global trade in food.

It is a massive mistake for governments to treat farming like other manufacturing industries. By doing so, they are not only making life impossible for small farmers, but also doing this country a grave disservice. Their stance is based on the entirely false premise that the present food system is operating in the public interest. In fact, the exact opposite is true. In the seven decades since the Second World War, the claimed increases in efficiency of food production have been achieved almost entirely at the expense of diminished natural and social capital.

The enlargement of average farm size, the abandonment of mixed farming in favour of continuous commodity production using chemical fertilisers and pesticides, the reduction of the agricultural workforce (ironically partially replaced by economic migrants) may have increased yields and lowered food prices, but at enormous cost, in terms of lost soil fertility, biodiversity, jobs, skills, social and cultural capital and diminished food security and negative impact on public health. Incredibly, none of these losses has been priced, as a result of which we are living in a world of dishonest food pricing, where the polluter doesn’t pay and, conversely, the farmers who are delivering public and environmental benefits are not rewarded financially for so doing. That is why we are witnessing the demise of the family dairy farm.

For me, it seems glaringly obvious that agriculture should not and must not be treated like any other industry. Although the human tragedy for a displaced farming family might arguably be no greater than that of a displaced miner, shipbuilder or steel worker, the long-term impact and hidden costs for society of losing the network of family farms where cows graze in a traditional way, and replacing these with a much smaller number of mega-dairy farms with ultra high-yielding cows living on concrete, will be orders of magnitude higher.

The asset-stripping operation and the relentless replacement of farms with factories has in large part been made possible by a brilliant sleight of hand, namely the failure to put an economic value on the damaging impact of intensive farming. An auditor might even declare it to be false accounting, but unfortunately most of us are failing to make the connection between these enormous hidden costs and the way in which we are already paying for them through general taxation, water charges or NHS bills. We need a radical new approach. The government’s 25-year plan for farming must serve the widest interests of the nation, not those of the largest farmers who expect to survive and benefit from much higher prices in future. For a start, let’s insist on the introduction of a fair trade milk label for family dairy farmers and include the requirement that the herd size be no larger than their capacity to walk to grass twice a day during the grazing season. This would reverse the trend towards ever-larger herds.

I have to stop writing now and get my herd in to be milked. It is hard work, but I often feel most alive and have my best thoughts during milking, which is perhaps no accident, since the human body was designed to work physically, something we have forgotten in a 21st-century world of offices and gymnasiums.

Tomorrow, our milk will be made into cheese, cheese from milk with a good story behind it, the kind of story that I was told during my London childhood and which many parents still read to their children at bedtime. Such stories inspired me to take up farming. If we let these stories become fiction, we will not only be compromising our own future, we will also be denying the next generation the chance to experience truly meaningful work on the land.

This article originally appeared in print in the Observer newspaper on Sunday 9th August

Photograph: Steph French