The purple twayblade is an orchid which can reach a height of 25 cm. It grows from a corm which has a few fleshy roots. The stem is bright green with purplish brown. From 5 to 33 flowers grow on a raceme; the petals of the flowers are greenish to pale purple, while the lip is violet with a fine network of reddish to purple veins. The flowers have no fragrance. The capsule measures 15 mm in length; the seeds measure about 0.35 mm in length and 0.12 mm in width.
The Purple Twayblade occurs primarily in the United States, from New England and Minnesota south to Arkansas and Alabama. In Canada it is found only in southern Ontario. In 1989, the plant was known from a total of eleven locations in Essex, Elgin and Kent counties and York Regional Municipality. Since then, a few small sites have been found in Windsor, but the plant has not been relocated at some former sites, and has generally declined. Most sites contain only a few plants, rarely more than 30. A population in the Oak Ridges Moraine area exceeded 300 plants in 1977, was reduced by habitat destruction to 34 plants in 1985, and had increased to 191 plants in 1989.
The Purple Twayblade requires open oak savannah and secondary successional, deciduous or mixed forest habitats. It will grow in partial shade, but does not tolerate dense shade; it is thus dependent on natural disturbances for its survival.
The main limiting factor, for the Purple Twayblade, is loss of habitat, due to the control of natural disturbances by humans and the conversion of its habitat to agriculture. The use of pesticides is also a limiting factor for this plant, since some populations have proved sensitive to specific pesticides. The collection of the Purple Twayblade by wildflower enthusiasts is also a potential limiting factor for this plant.
The Purple Twayblade is protected under the federal Species at Risk Act (SARA).
More information about SARA, including how it protects individual species, is available in the Species at Risk Act: A Guide.
The Purple Twayblade occurs in the Ojibway Prairie Provincial Nature Reserve and the municipal Black Oak and Tallgrass Prairie Heritage Parks.
PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.
Purple Twayblade (Liparis liliifolia) is a terrestrial perennial orchid whose leafy flowering shoot develops from a bulbous corm. The plant attains a height of about 25 cm. The flowering stalk of five to 33 flowers arises from the centre of two ovals to elliptic fleshy leaves. Flowers consist of a prominent, broad violet-mauve lip (10-14 mm long) streaked with a fine network of reddish-purple veins. The two lateral petals are linear to thread-like and greenish to pale purple. Three greenish-white narrowly lanceolate sepals surround the petals. The fruit develops into an erect ellipsoid capsule about 15 mm long.
This small inconspicuous orchid extends across southern Ontario to southwestern Quebec as a series of scattered populations. The discovery of several new populations in recent years has extended its known range in Canada. The few individuals present in the majority of the populations and the overall small size of the entire Canadian population places the species at continued risk from chance events.
The Minister of the Environment is the competent minister under SARA for the Purple Twayblade and has prepared this strategy, as per section 37 of SARA. To the extent possible, it has been prepared in cooperation with the Province of Ontario and the Province of Quebec.
The Multi-species Action Plan for Kouchibouguac National Park of Canada and associated National Historic Sites of Canada applies to lands and waters occurring within the boundaries of the four sites: Kouchibouguac National Park of Canada (KNP) and other land managed by Parks Canada in the Northern New-Brunswick Field Unit offering adequate habitat for the species targeted in this action plan (Fort Beauséjour – Fort Cumberland National Historic Site of Canada (NHS), Beaubassin – Fort Lawrence NHS, Grand-Pré NHS). The plan meets the requirements for action plans set out in the Species at Risk Act (SARA) (s.47) for species requiring an action plan and that regularly occur in these sites. Measures described in this plan will also provide benefits for other species of conservation concern that regularly occur in KNP and associated NHS.
His Excellency the Governor General in Council, on the recommendation of the Minister of the Environment, acknowledges receipt, on the making of this Order, of assessments conducted under subsection 23(1) of the Species at Risk Act by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) with respect to the species set out in the annexed schedule.
Biodiversity is rapidly declining worldwide as species become extinct. Today’s extinction rate is estimated to be between 1 000 and 10 000 times higher than the natural rate. Biodiversity is positively related to ecosystem productivity, health and resiliency (i.e. the ability of an ecosystem to respond to changes or disturbances), and, given the interdependency of species, a loss of biodiversity can lead to decreases in ecosystem function and services (e.g. natural processes such as pest control, pollination, coastal wave attenuation, temperature regulation and carbon fixing). These services are important to the health of Canadians, and also have important ties to Canada’s economy. Small changes within an ecosystem resulting in the loss of individuals and species can therefore result in adverse, irreversible and broad-ranging effects.
Under Canada’s Species at Risk Act (SARA), the foremost function of COSEWIC is to “assess the status of each wildlife species considered by COSEWIC to be at risk and, as part of the assessment, identify existing and potential threats to the species”.
COSEWIC held two Wildlife Species Assessment Meetings during the past year assessing the status or reviewing the classification of a total of 92 wildlife species.
As part of its strategy for protecting wildlife species at risk, the Government of Canada proclaimed the Species at Risk Act (SARA) on June 5, 2003. Attached to the Act is Schedule 1, the list of the species that receive protection under SARA, also called the List of Wildlife Species at Risk.
Please submit your comments by
February 8, 2012 for species undergoing normal consultations
November 8, 2012 for species undergoing extended consultations.
Environment and Climate Change Canada’s Three-Year Recovery Document Posting Plan identifies the species for which recovery documents will be posted each fiscal year starting in 2014-2015. Posting this three year plan on the Species at Risk Public Registry is intended to provide transparency to partners, stakeholders, and the public about Environment and Climate Change Canada’s plan to develop and post these proposed recovery strategies and management plans. However, both the number of documents and the particular species that are posted in a given year may change slightly due to a variety of circumstances.
Last update March 17, 2017