SOME years ago, BBC Scotland hired an expensive demographics wonk to look at the station’s audience profile. Among his more startling findings – along with the alarming news that people tended to switch off the radio at the end of programmes – was that the “typical” listener to an arts programme that I then presented was a 59-year-old retired farmer in Perthshire. My first reaction was that farmers don’t ever really retire, surely? My second was that maybe only in lush Perthshire can they afford to.

In his personal and passionate new account of British farming en route to Brexit, Charlie Pye-Smith revives a very similar demographic detail, the notion that the average age of a British farmer in the 2000s is a worryingly aged, if not retired, 59. But Pye-Smith quickly goes on to clarify a less obvious reality which is that while most of the names on deeds and tenancy agreements do, indeed, fall into that age bracket, the real farming is often being done by a following generation, or sometimes two, and that the land isn’t stewarded by crumbly geronto-pastoralists, but by a reassuringly mixed profile of ages, philosophies and methods. The old association of farming with Conservatism was severed by Margaret Thatcher. The casual assumption that farmers are unshakably small-c conservative doesn’t stand up to prolonged examination. Perhaps the single strongest impression coming out of Pye-Smith’s book is the healthy co-existence of tiny hill farms where RS Thomas’s solitary man “pens a few sheep in a gap of cloud”, to hyper-modern operations that rely on computer technology, sophisticated genetic profiling and advanced agricultural chemistry.

Pye-Smith (which in an author concerned with our food supply must count as nominative determinism) has travelled the length and breadth of the country, looking at the different branches of contemporary farming, dairy, beef, lamb, poultry, arable and vegetables, and examining some of the more persistent misconceptions about the economics and ethics of our national larder. Land of Plenty isn’t a diatribe against monoculture. It isn’t particularly “green” in its emphases and assumptions. And it doesn’t always tick the sort of boxes that need to be ticked in Islington or the West End of Glasgow. Pye-Smith assembles strong evidence that outdoor-raised, “free-range” meat doesn’t necessarily come with higher welfare ticks than indoor and “intensive”, the latter word having acquired a steadily darkening aura through the era of so-called “organic” food. The book begins in Stella Gibbons rather than Laurie Lee mode with a childhood memory of a farmer (a Mr Codd) castrating his pigs with a razor and throwing the testicles to his dogs, but Pye-Smith is always keen to show that farmers get just as emotional as the rest of us, even if they do it in a gruff and manly way. When he admits to a farmer near Melton Mowbray that he always thinks that lambing is a very emotional time, the farmer doesn’t just shrug and spit and mutter “Nah, they’s aaal just mutton to I” but replies quietly “Yet, it is, isn’t it?”, and that quiet, maybe counter-intuitive response sets the tone for the book.

Its great strength is that it is neither a manifesto nor a jeremiad. Just as there is no “typical” radio listener, there is no such thing as a typical farmer. Only media wonks and some politicians bundle up “agriculture” into a single category and start labelling it “in decline”, “in crisis”, “bankrupt”, “subsidy-dependent”, “doomed”. Land of Plenty is a series of human encounters, each particular and specific, sometimes to place, sometimes to circumstance, sometimes to personal conviction. What it delivers is a rapid montage of British agriculture adapting to changing conditions, some of which are under human control (like those favourite and much-abused pantomime villains, the EC's agriculture commissioners), some of it (like climate change) not. It is a gentle reminder that knowing the name and county of the farmer who produced our spuds doesn’t give us much insight into how he lives or produces them, and that the sweetly bucolic branding of produce as coming from “Merrydene Farms” or somesuch very often disguises an industrial operation of some scale. The last time my father took a flight from Glasgow to London he was struck by how “green and pleasant” our apparently crowded land still remains and how much it still is a land of plenty. The view from ground level is, of course, more complex.