Native British Black Poplars are being saved from extinction

Black Poplar trees were used widely as a building material and for farm equipment but their natural habitat has been reduced by housing and farming.

The Highways Agency is planting 24 of the trees along the A421 Great Barford Bypass, near Bedford, this month.

Black Poplars have become one of Britain's rarest native trees - despite once being common in the region.

In 1993, environmental scientists predicted the species would be extinct in Britain within 20 years because land development was lowering the water table in many places and this was destroying the trees' natural habitat.

'Traditional look'

The Highways Agency has now started a planting programme for the Black Poplar on its road schemes.

The Great Barford bypass aims to remove 90% of traffic flowing through a rural village and will eliminate a bottleneck on the route from Milton Keynes to Cambridge.

Black Poplar trees will be used in landscaping to bring back a traditional look to the countryside, the Highways Agency said.

Constable's painting the Hay Wain hangs in the National Gallery, London. It is based on a site near Flatford on the River Stour on the border of Suffolk and Essex.

A hay wain, a type of horse drawn cart, stands in the water in the foreground of the painting.