The engine throbbed, the combine harvester bounced briefly on the spot, the reel began to turn and, with no driver on board, the most expensive crop in Britain went under its blades.

The robot-tended cereal was the first ever to be grown entirely by machines

In Shropshire, after a drone buzzed overhead to check that the barley wasn’t too wet, a small robot-controlled vehicle harvested the first crop in the world to have been grown entirely by machines with no human having set foot in the field.

Although some larger agricultural vehicles are already semi-autonomous, the researchers behind the Hands-Free Hectare project believe that only by automating every aspect of the cycle and working with smaller machines can Britain’s farmers overcome a shortage of labour and near 20-year plateau in crop yields.