Dig suggests answers to Roman field mystery

Archaeologists believe they have solved an early Roman farming mystery.

The team at Cotswold Archaeology were excavating a claggy site at Littleport, Cambridgeshire, in 2022 when they came across shallow cultivation trenches.

Experts previously suggested similar parallel trenches might have been bedding channels for vegetables - or even vineyards.

Instead, Richard Mortimer thinks they were part of an agricultural system called marling, used to make marginal land more productive, so more wheat could be grown to "make this new British province pay for itself".

"Wheat was the gold and the British were good at it before the Romans turned up; they knew that, and they wanted more of it," said Mortimer, a post-excavation project manager at Cotswold Archaeology.

Without pollen evidence, he cannot be certain what was grown in the trenches, but he thinks wheat was most likely because it was a staple item of the Roman diet, it was easy to transport and, unlike vegetables, it was less likely to spoil.

The trenches found at Littleport dated to between AD70 and 80, at least a decade after Boudicca's failed revolt (AD60 to 61).

Mortimer said: "Things are calming down and there's a big push to increase the value of the land that the Romans have just taken and settled, to produce more crops - and more wealth."

The four-hectare site (9.8 acres) was on marginal, clay land, difficult to plough and typically seen as fit for pasture.

"Crisply cut" parallel trenches were discovered, about 8cm (3in) deep, nearly one metre (3.2ft) wide and found every four or five metres (13 to 15ft).

"They were one of the crispest things you find in archaeology because they are dug and backfilled immediately," he explained.

Since the first early Roman trench system was discovered in Wollaston, Northamptonshire, about 35 years ago, 38 clear examples have been excavated in Cambridgeshire, Suffolk, Northamptonshire and Bedfordshire.

Mortimer rejected suggestions they could be vineyards, because these typically required sloped sites and plenty of sunshine, not "low, unusable wet land".

His light bulb moment came while reading a 19th Century description of farm workers marling similar fields.

Mortimer said: "You can improve the pH of your soil and the body of your soil by digging a hole, taking the clay - known as marl - out and sticking it in the top and spreading it over the existing soil.

"And I'm thinking, well, 'Why is that any different to what I'm seeing?' It's the same thing."

It was a process known to both the Britons and the Romans.

The back-breaking work of creating acre upon acre of parallel trenches could have been done by soldiers or farm workers, although slave labour was probably plentiful after Boudicca's revolt.

"It may not be true; I'm not claiming it's necessarily, definitely true, but I think it works better than all the other possible explanations for the trenches so far," he added.

His research has been published by The Proceedings of the Cambridge Antiquarian Society.

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