The global assessment of temperate slipper orchids, occurring in North America, Europe and temperate Asia, reveals that 79% of these popular ornamental plants are threatened with extinction. This is mainly due to habitat destruction and over-collection of wild species for local and international trade, despite the fact that international trade in all species of slipper orchids is regulated. Temperate slipper orchids are among the best-known and most widely illustrated of all flowering plants, with characteristic slipper-shaped flowers which trap insects to ensure pollination.
“What was most surprising about this assessment was the degree of threat to these orchids,” says Hassan Rankou, the IUCN Species Survival Commission’s (SSC) Red List Authority for the Orchid Specialist Group, which is hosted by the Royal Botanic Gardens, Kew. “Slipper orchids are popular in the multimillion-dollar horticultural industry. Although the industry is sustained by cultivated stock, conservation of wild species is vital for its future.”
The Endangered Freckled Cypripedium (Cypripedium lentiginosum) has fewer than 100 individuals remaining in south-eastern Yunnan in China and Ha Giang province of Viet Nam. Its decline is due to over-collection and deforestation. Also Endangered, Dickinson's Cypripedium (C. dickinsonianum) is known only from a few scattered populations in Mexico, Guatemala and Honduras. Its open forest habitat is being cleared for agriculture and the lopping of trees is changing the environmental conditions which allow orchids and other under-storey plants to thrive.