And Peak Park ecologists revealed the unusual dark red helleborine orchids dug up near Stoney Middleton were likely to die.

Even legal attempts to move the orchids – which are found in only five sites in Britain – have often failed due to the difficulty of replanting them.

Rhodri Thomas, Peak District National Park Authority environment manager, said: "The actions of the thieves have damaged a nationally important wildlife site and put a rare plant under further threat."

It is illegal to pick rare plants, or to remove any plants without the landowner's permission.

Police wildlife crime co-ordinator Pete Charleston said: "These orchids are as much a part of our heritage as a painting in an art gallery or museum and so deserve protection too.

"We are very keen to hear from anybody who has information about the theft of the dark red helleborine orchids in the Stoney Middleton area or any similar incidents," he added.

The orchids - also known as epipactis atrorubens - are 15cm to 30cm tall, with a hairy stem and up to 20 flowers.

Anyone with information should call 0845 123 3333.