Vascular Plants

Name: Small White Lady's Slipper Orchid Scientific Name: Cypripedium candidum Status: Endangered Provincially and Nationally Details & Range Map: Royal Ontario Museum (R.O.M.)

Vascular plants comprise the majority of the familiar plant groups such as flowering plants, trees, shrubs, herbs and ferns. There are over 260,000 species of vascular plants globally, of which 5,111 species are found in Canada.

There are about 3,099 species of vascular plants in Ontario. Approximately 21% of these species are of provincial conservation concern.

According to the General Status of Species in Canada (2010), there are 25 species in Ontario that are extirpated, 62 species at risk (e.g. Red Mulberry, Small White Lady's Slipper Orchid and Butternut), 427 species that may be at risk, 149 species that are characterized as sensitive (species that are not believed to be at risk of immediate extirpation or extinction but may require special attention or protection to prevent them from becoming at risk) and 1,312 are secure. There are another 73 species that have an undetermined status (species for which insufficient data, information, or knowledge is available with which to reliably evaluate their general status). Approximately 1,051 vascular plant species are considered exotic in Ontario. In the General Status of Species in Canada (2010), ‘exotic’ refers to species that have been moved beyond their natural range as a result of human activity. Provincially, the term invasive (or invading) species is used to describe introduced species whose introduction or spread threatens the environment, the economy or society, including human health.

Threats to vascular plants include habitat loss and habitat degradation. Over-harvesting is another threat for some species, particularly those valued for medicinal properties or their beauty (Showy Lady's-slipper). The impact of exotic species has also become more apparent with the establishment of plants such as Purple Loosestrife, European Buckthorn and Spotted Knapweed.

For more information on vascular plants species and their current status, see the Natural Heritage Information Centre (NHIC).

For more information on Species at Risk designations and their current status, see the Species at Risk in Ontario (SARO) List and the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) website.

Photography
Michael J. Oldham