Cornish hedge

A Cornish hedge is a style of hedge built of stone and earth found in Cornwall, south-west England. Sometimes hedging plants or trees are planted on the hedge to increase its windbreaking height. A rich flora develops over the lifespan of a Cornish hedge. The Cornish hedge contributes to the distinctive field-pattern of the Cornish landscape, and form the county's largest semi-natural wildlife habitat.

A Cornish hedge has two sides which are built by placing huge stone blocks into the earth and packing them in with sub-soil. Smaller interlocking rocks are used to build the hedge high until it reaches a level when random turns into neat rows of square stones called "edgers". Two inches of grass are sliced from the ground and stuck on top of the structure with sticks. — Article in The West Briton

The hedge is slightly wider at bottom than at the top, because of the large "grounder" stones at the base. The structure is very stable and will stand for a hundred years or more. The hedge has two stone faces with soil between the two walls. Bushes such as gorse may grow on the top, rooted in the soil between the walls. It is called a hedge because of its living component. A professional hedger can build about a metre of double-sided hedge in a day.

The archaeologist Francis Pryor observes:

A visitor to Devon and Cornwall cannot fail to be impressed by the massive hedgebanks that so often confine the road into something approaching a ravine or tunnel. The hedgebanks of Devon are sometimes thicker and more massive than those of Cornwall, which are often remarkably thin and tall.

There are about 30,000 miles (48,000 km) of hedges in Cornwall today, and their development over the centuries is preserved in their structure. The first Cornish hedges enclosed land for cereal crops during the Neolithic Age (4000–6000 years ago). Prehistoric farms were of about 5 to 10 hectares (12 to 25 acres), with fields about 0.1 hectares (0.25 acres) for hand cultivation. Some hedges date from the Bronze and Iron Ages, 2000–4000 years ago, when Cornwall's traditional pattern of landscape became established. Others were built during the Mediaeval field rationalisations; more originated in the tin and copper industrial boom of the 18th and 19th centuries, when heaths and uplands were enclosed.

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