Species at Risk within Tallgrass Vegetation Communities

Staus and Protection 

In Ontario there are twenty-three plant species associated with Tallgrass Vegetation Communities that are regulated as Endangered, Threatened or Special Concern within schedules of the Species at Risk Act (SARA) and Endangered Species Act, 2017 (ESA, 2017). Plant species considered Endangered and Threatened receive protection in Ontario under the ESA, 2017 and in Canada under the federal SARA. Protection prohibits actions such as killing, harming, possessing, selling or trading of the plants. One plant species associated with Tallgrass Vegetation Communities is extirpated. It was last seen in 1978 near Thamesville, Ontario. Extirpation means extinction in Ontario.

Extripated in Schedule 1 of SARA and Schedule 1 of ESA, 2017:
  • Illinois Tick-trefoli (Desmodium Illinoense)
Endangered in Schedule 1 of SARA and Schedule 2 of ESA, 2017:
  • Skinner’s Agalinis (Agalinis skinneriana)
  • Small White Lady’s Slipper (Cypripedium candidum)
  • Slender Bush Clover (Lespedeza virginica)
  • Pink Milkwort (Polygala incarnata)
  • Hoary Mountain Mint (Pycnanthemum incanum)
  • Virginia Goat’s-rue (Tephrosia virginiana)
  • Bird’s Foot Violet (Viola pedata)
  • Gattinger’s Agalinis (Agalinis gattingeri)
  • White Prairie Gentian (Gentiana alba)
  • Eastern Prairie Fringed Orchid (Platanthera leucophaea)
  • Stiff-leaved Showy Goldenrod (Solidago rigidiuscula)
  • Spotted Wintergreen (Chimaphila maculate)
  • American Columbo (Frasera caroliniensis)
Threatened in Schedule 1 of SARA and Endangered in Schedule 2 of ESA, 2017:
  • Western Silvery Aster (Symphyotrichum sericeum)
  • Colicroot (Aletris farinosa)
Threatened in Schedule 1 of SARA and Schedule 3 of ESA, 2017:
  • Purple Twayblade (Liparis liliifolia)
  • Dwarf Hackberry (Celtis tenuifolia)
  • Hill’s Thistle (Cirsium pumilum var. hillii)
  • Dense Blazing Star (Liatris spicata)
  • Willowleaf Aster (Symphyotrichum praealtum) 
Special concern in Schedule 1 of SARA and Schedule 4 of ESA, 2017:
  • Climbing Prairie Rose (Rosa setigera)
  • Riddell’s Goldenrod (Solidago riddellii)

For further information visit the Ontario Ministry of Natural Resources Species at Risk website at: http://www.mnr.gov.on.ca/en/Business/Species/index.html

Canada Species at Risk Act website at:


Prairie plant Species at Risk occur primarily in Southwestern Ontario as well as the edge of the Ontario-Manitoba border. Many of these plants are found more commonly in the Midwestern United States and reach their northeastern range limits in southwestern Ontario.


These plants flourish in open full sun habitats such as tallgrass prairies with sandy soils. They can also be found in openings of savannahs and woodlands and in anthropogenically disturbed sand pits, railroads, roadsides and abandoned agricultural fields.


Current threats to the Ontario populations include natural succession by woody vegetation, lack of fire, invasive plant species, hybridization, erosion, trampling caused by ATV use and hiking, illegal collection of plants for transplanting to gardens, cottage, road, and agricultural expansion.