White Prairie Gentian

(Gentiana alba)

Status: Endangered (ESA 2008, COSEWIC 2010)

Table of Contents:

Species Identification
Habitat and Biology
Threats/Reasons for Being at Risk
Conservation and Recovery Strategies
How You Can Help

Species Identification:

The White Prairie Gentian is a sprawling, perennial flowering plant that can reach heights of up to 90 cm. The leaves are large, smooth, oval-shaped, and yellow-green in colour. The leaves are also arranged in an opposite pattern. White Prairie Gentian can have up to 12 stems, with dense clusters of white to greenish-white bottle-shaped flowers on the end of each stem. This species produces seed pods that break to release hundreds of winged seeds to be dispersed by wind.

Habitat and Biology:

The White Prairie Gentian’s range spans across Eastern North America. Its U.S range extends from Pennsylvania, Ohio, southern Michigan, Wisconsin and Minnesota in the north to Iowa, eastern Nebraska, Kansas and Oklahoma in the west to Arkansas, Kentucky, and West Virginia in the south. The Canadian population of White Prairie Gentian is believed to occur only in the oak savannas on the Walpole Island First Nation in southern Ontario. Historically, there were populations on the limestone alvars in Northumberland County and Essex County, but they have not been seen for over a century. The White Prairie Gentian is believed to be extirpated from The Land Between, meaning that it was once known to occur here, but no longer does. This also means that there is potential for the species to occur here again in the future, if the appropriate actions are taken. The range of this species in Ontario is not believed to have changed since it was initially assessed by COSEWIC in 1991, despite searches in 2008. Less than 3% of the original Ontario prairie habitat on which the White Prairie Gentian depends remains in existence today.

Map taken from Government of Canada: https://www.sararegistry.gc.ca/virtual_sara/files/cosewic/sr_white_prairie_gentian_0911_eng.pdf

In Canada, White Prairie Gentian has very specific habitat requirements since it grows exclusively in oak-hickory savannas and limestone alvars. White Prairie Gentian requires an open, dry, sunny environment, thus relying on natural forest fires to prevent vegetation growth and canopy closure. White Prairie Gentian is almost exclusively pollinated by Bumblebees, and flowers from mid August to late September. Closed-bottle shaped flowers are believed to be designed to limit self-fertilization, so as to enhance the genetic diversity of the population as much as possible. The fruit pod splits in early October, releasing winged seeds that are distributed by the wind. Seedlings are strong and fast growing but need approximately three months of cool, moist conditions to grow.

Threats/ Reasons for being at Risk:

1. Habitat loss and degradation: Habitat loss and degradation as a result of human development and expansion has already had a negative impact on White Prairie Gentian, and could be the reason for the extirpation of the historic populations of the species. Housing shortages on Walpole Island First Nation have resulted in construction on and near White Prairie Gentian habitat, resulting in a further loss of already limited habitat.

2. Fire suppression: Fire suppression in White Prairie Gentian habitat due to the presence of homes and other human infrastructure nearby is resulting in vast changes of critical open savanna habitat required by White Prairie Gentian. Fire suppression allows plants, shrubs and saplings to grow taller than usual for prairie habitats, closing the canopy and creating shade that does not allow sun loving plants like the White Prairie Gentian to grow.

3. Disturbance and harm: Trampling and damage from hiking, dog walking, ATVing, and snowmobile use can harm or kill individuals within a population, limiting the number of remaining healthy individuals and decreasing the genetic diversity of a population. Soil compaction as a result of human activity in White Prairie Gentian habitat can also alter the environment, rendering the habitat unsuitable for the plant.

4. Exotic, invasive and introduced species: The prairie savanna habitat on Walpole Island First Nation is facing threats from several invasive species such as European Common Reed (also known as Phragmites), White Sweet Clover, and Black Locust that have the potential to outcompete White Prairie Gentian for resources, and block the sun from reaching the plants.

Conservation and recovery strategies:

The only known remaining population of White Prairie Gentian is being closely monitored, and the viability of the remaining seeds are being studied. In 2009, the Walpole Island Heritage Centre acquired some of the prairie savanna habitat on which the White Prairie Gentian is found for conservation, protecting the acquired section from habitat degradation as a result of human development or other activities.

In 1998, World Wildlife Fund (WWF) Canada and the Ministry of Natural Resources & Forestry published a Recovery Plan for Tallgrass communities in Ontario. The plan, which is still in use today, outlines an approach to conserve tallgrass ecosystems as a whole, and in so doing protect the hundreds of species that depend on them to survive. Tallgrass Ontario, a non-profit dedicated to realizing the goals and objectives of the Grassland Community Recovery Plan, has a great deal of resources for landowners and the general public on the importance of grassland communities, the species that depend on the landscape, and resources for what landowners can do to protect and support the grassland habitat on their property. For more information on this organization, visit https://tallgrassontario.org/wp-site/.

How can you help?

Learn how to identify White Prairie Gentian and report any sightings of the plant in the region to The and Between or iNaturalist with a photo and GPS point of where it was found.
As Bumblebees are the primary pollinators of White Prairie Gentian, supporting Bumblebees and other pollinators by planting pollinator friendly gardens that have blooms throughout the spring and summer will help support the White Prairie Gentian.
Volunteer with Tallgrass Ontario as a prescribed burner to help control the overgrowth of plants that threaten to close the prairie canopy and outcompete prairie species.
Keep your property natural and encourage the growth of native plant species.

Additional Resources:

Government of Ontario’s White Prairie Gentian SAR page
Learn to identify the White Prairie Gentian (also known as Pale Gentian) on iNaturalist

Sources:

Government of Ontario. 2014. White prairie gentian. Retrieved from: https://www.ontario.ca/page/white-prairie-gentian

Government of Ontario. 2016. White Prairie Gentian Recovery Strategy. Retrieved from: https://www.ontario.ca/page/white-prairie-gentian-recovery-strategy

COSEWIC. 2001. COSEWIC assessment and update status report on the White Prairie Gentian Gentiana alba in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vi + 13 pp. https://www.sararegistry.gc.ca/virtual_sara/files/cosewic/sr_white_prairie_gentian_0911_eng.pdf

Tallgrass Ontario. N.d. Recovery Plan. Retrieved from: https://tallgrassontario.org/