It’s one of my earliest memories: local pig farmer Ernie Pepper leaning out of his car most Sunday mornings, to tell my father – the vicar – that he had been ruined. Either the weather or the subsidies had done for him, and the bailiffs would be in by the end of the week. Even at the tender age of five or six, I could never quite equate Ernie’s announcements with the fact that they were always delivered from a brand-new, top of the range car – a Humber, as I recall.

Thus it was that I formed a stereotypical picture of British farmers as people who were always grumbling, but who actually did rather well for themselves. It’s a picture that’s roundly disabused by Richard Bean’s Harvest. The play follows an East Yorkshire farming family’s ups and downs through four generations, beginning in 1914. That year an army sergeant turns up, after men and the farm’s ploughing horses. William will go and fight, it’s decided, while brother Albert stays behind to run the farm.

William loses both legs, and spends the rest of his long life in a succession of wheelchairs – by the time he reaches his 100th birthday, he has a high-speed electric model.

The wheelchairs are a metaphor. In Ian Dunn’s superb performance (directed by Wilson Milam), it’s William who is always embracing change, and who increasingly develops a robust sense of humour. When Albert (Gareth Farr) is accidentally shot dead, his wife Maudie (Leah Whitaker) cries: “What are we going to do now?” William triumphantly answers: “Pigs”. Albert was always dead against pigs. The audience laughs, but is not quite sure whether that’s distasteful in the circumstances – it’s one of several occasions when playwright Bean enjoys testing the audience’s sense of humour.

Bean has several other aces up his sleeve as assorted new characters appear. There’s Stefan (Gunnar Cauthery), a German prisoner of war, who joins the farm in 1944, and stalwart Laura (Katie Wimpenny).

Then there’s the hilarious Titch (Adrian Hood), who announces he is going to be the new pig man – walking out of his interview every time he’s “insulted” by an awkward question, he says: “Do yer see? I’ve sat doon again” when he returns.

There’s a tilt at soft urbanites in the local squire (Dickon Tyrrell), who comes round to buy manure: “No man can talk authoritatively until he’s sold s**t to the aristocracy,” proclaims William. Disastrously named Primrose, the squire writes books about his Arctic travels, although he’s never actually been there.

So is this a stage version of The Archers? Certainly the sexual shenanigans are worthy of a soap, and the spot-on, unsanitised, writing and acting in this Royal Court/Oxford Playhouse joint production keep you hooked from scene to scene. But to me, Harvest delivers a much more vivid picture of real-life farming.

Harvest continues at the Oxford Playhouse until Saturday. Tickets: 01865 305305 or online at www.oxfordplayhouse.com