CONSERVATION chiefs are launching a bid to permanently ban traffic from three picturesque lanes that have been churned up by off-road vehicles.

The lanes on Pockley Moor were temporarily closed last year because of their condition, and the highways authority has signalled its intent to repair and reopen them.

But the North York Moors National Park authority is now being asked to back a move to make the closures permanent and effectively reduce the lanes' status to that of bridleways.

Head of park services Rich-ard Gunton said the tracks crossed a fine example of the moorland landscape, but the damage caused by off-roaders had degraded its qualities.

In a report to the authority he said: "Pockley Moor has the feeling of being very isolated and unspoilt. There are extensive views into Bransdale and its surrounds and very little sign of human occupation."

He said vehicle access had caused significant damage in the past to the tracks and the moorland and the simple repairs planned by the highways authority would not prevent severe erosion.

He said that the erosion made the tracks unsuitable for horses, hikers or cyclists and was a visual intrusion on a prominent and exposed landscape.

Disturbance was also caused to other users by engine noise and the physical presence of vehicles on the narrow tracks.

There was also continued damage to the moorland as vehicles tried to find their way around the worst rutted or wet areas.

Pockley Moor is also a designated Site of Special Scientific Interest, a Special Protection Area and a candidate Special Area for Conservation under the European Habitats Directive.

English Nature has expressed its concern about the likely impact of the use of the tracks following any repairs.

"It seems clear that the proposed works and reopening of these routes would run contrary to both National Park purposes and the objectives of the National Park management plan," said Mr Gunton.

The main route concerned begins at Beadlam Rigg and follows Aldergate Bank before descending Rollgate Bank, crossing Pockley Moor and joining the Helmsley to Bransdale road.

The other two are joining routes from Beadlam Rigg and Birk Nab Farm