Long dry spells in the spring and the recent hot temperatures have sparked the fastest start to harvest since at least 2006, according to industry analysis.

The arid conditions have hit crop growth, with some farmers reporting barley yields down by 25pc, with the bulk of the wheat harvest still to come.

Irrigation reservoirs and river flows are running low, and the Environment Agency has implemented hundreds of temporary bans on water abstraction licences – heaping pressure on rain-starved root crops in parched fields.

Meanwhile, livestock farmers are struggling to find good grass on grazing land, and a lack of forage is impacting on winter animal feed supplies.

But despite the challenges, some of the region's farms have reported good grain quality and better-than-expected yields at the start of the harvest.

Andrew Blenkiron, managing director of Elveden Farms, on the Norfolk/Suffolk border near Thetford (Image: NFU)

Andrew Blenkiron is managing director of Elveden Farms on the Norfolk/Suffolk border near Thetford, which is already about two-thirds through its cereal harvest - including all its winter barley and most of its spring barley.

He said cereal yields are down about 25pc compared to the five-year average, although the grain size and quality were "actually pretty good", while malting barley samples looked "promising". He expects similar results from the wheat, due to be combined next week.

But Mr Blenkiron said these crops benefited hugely from the availability of irrigation water from the estate's reservoirs and groundwater boreholes.

"It would have been worse if we had not made that strategic decision to apply water in April and May to the cereal crops," he said.

"Generally I would say that investment has paid off, but 25pc down is still quite a significant chunk, particularly when the cereals are not worth anywhere near the amount they were last year.

"I think on this land, we could have seen a 50pc reduction in yield but very thankfully we had some water available, and the winter barley had 30mm applied to it in the middle of April, which kept it hanging on longer than it might have done otherwise.........

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