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Purple Twayblade

Purple Twayblade
   Photo: ROM

Features: Purple Twayblade (Liparis liliifolia) is a small inconspicuous orchid that has a very limited distribution in this province. The "lip" of the orchid flower is violet-mauve in colour, and the threadlike side petals are green to purple. In Ontario it grows in oak savannah, and in relatively open, successional mixed wood and hardwood habitats.

Status: Threatened Provincially and Nationally

Range: The range of Purple Twayblade extends from the eastern seaboard of the United States, west through southern Ontario and the midwestern United States, and south to Georgia, Alabama, Arkansas and Missouri. Although common in parts of its main range in the United States, Purple Twayblade is very localized in Ontario, which is at the northern limits of its distribution. In the late 1980's, Purple Twayblade was known from 11 sites in southern Ontario. Since then, these populations have declined or disappeared, and only a few very small new populations have been located.

Threats: Habitat loss resulting from development has been responsible for the loss of approximately five stands of this orchid in Ontario. Natural succession is a problem at some of the remaining sites, as the orchids cannot tolerate conditions of shade created by dense vegetation.

Protection: Under Ontario's Endangered Species Act, 2007, Purple Twayblade is protected from being collected, harmed, or killed. The Natural Heritage component of the Provincial Policy Statement under Ontario's Planning Act provides for the protection of significant habitat of endangered species. Two sites in Windsor are on public land where they receive protection and management; at the Tallgrass Prairie Heritage Park, prescribed burns have benefited the species by maintaining open habitat. International trade in orchids or their parts is controlled under CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora).

Text Sources: Allen 1986; McNicholl 1991; White 1998

Last Modified Date: June 2011

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