A colour photo of willowleaf aster
Photo: Allen Woodliffe

Willowleaf Aster is an herbaceous, perennial plant with smooth, waxy stems, reaching 50 to 150 cm in height. Clusters of pale lavender daisy-like flowers are produced in the fall. In Canada, Willowleaf Aster occurs only in southwestern Ontario.

Protecting and recovering species at risk in Ontario

Species at risk recovery is a key part of protecting Ontario’s biodiversity. Biodiversity – the variety of living organisms on Earth – provides us with clean air and water, food, fibre, medicine and other resources that we need to survive.

The Endangered Species Act, 2007 (ESA) is the Government of Ontario’s legislative commitment to protecting and recovering species at risk and their habitats. As soon as a species is listed as extirpated, endangered or threatened under the ESA, it is automatically protected from harm or harassment. Also, immediately upon listing, the habitats of endangered and threatened species are protected from damage or destruction.

Under the ESA, the Ministry of Natural Resources and Forestry (the Ministry) must ensure that a recovery strategy is prepared for each species that is listed as endangered or threatened. A recovery strategy provides science-based advice to government on what is required to achieve recovery of a species.

Government response statements

Within nine months after a recovery strategy is prepared, the ESA requires the Ministry to publish a statement summarizing the government’s intended actions and priorities in response to the recovery strategy. The recovery strategy for the Willowleaf Aster (Symphyotrichum praealtum) in Ontario was completed on November 22, 2013.

The response statement is the government’s policy response to the scientific advice provided in the recovery strategy. All recommendations provided in the recovery strategy were considered and this response statement identifies those that are considered to be appropriate and necessary for the protection and recovery of the species. In addition to the strategy, the response statement is based on input from stakeholders, other jurisdictions, Aboriginal communities and members of the public. It reflects the best available traditional, local and scientific knowledge at this time and may be adapted if new information becomes available. In implementing the actions in the response statement, the ESA allows the Ministry to determine what is feasible, taking into account social and economic factors.

Willowleaf Aster is an herbaceous, perennial plant with smooth, waxy stems, reaching 50 to 150 cm in height. Clusters of pale lavender daisy-like flowers are produced in the fall.

In Canada, Willowleaf Aster occurs only in southwestern Ontario.

Moving forward to protect and recover Willowleaf Aster

Willowleaf Aster is listed as a threatened species under the ESA, which protects both the plant and its habitat. The ESA prohibits harm or harassment of the species and damage or destruction of its habitat without authorization. Such authorization would require that conditions established by the Ministry be met.

The distribution of Willowleaf Aster ranges from southwestern Ontario and the northeastern United States to northern Mexico. In Canada, the species occurs only in southwestern Ontario. Within the province, there are nine natural populations confirmed to be in existence. The largest of these populations, known as the Windsor-LaSalle North population, is made up of 13 separate sub-populations. An additional two restoration populations were recently established in the Windsor and Chatham-Kent areas in accordance with an authorization under the ESA. An additional four populations of the species have been confirmed extirpated, and the status of another four populations remains unknown due to the absence of species survey work at those sites in recent years.

Willowleaf Aster reproduces sexually through cross-pollination, which generates seeds that are genetically distinct from parent plants. The species also reproduces vegetatively from rhizomes, which generates multiple flowering stems that are genetically identical to the parent plant (i.e., clones). Given the two ways in which this species reproduces, it is difficult to determine how many genetically distinct individuals are present within each population.

Willowleaf Aster occurs in tallgrass prairie, oak savannah, thickets, meadows, and woodland clearings and edges. Where site conditions are suitable, this species is also known to occur in open habitats created by human activities, such as railway embankments, roadsides, utility corridors, abandoned agricultural fields, and vacant city lots. To remain suitable for the species, the habitats of Willowleaf Aster depend on periodic disturbance such as fire, drought, or even vegetation clearing, provided it is undertaken in a manner that is compatible with the species.

The primary threats to Willowleaf Aster are habitat loss and degradation resulting from development, agricultural conversion and natural succession. Other important threats include invasive species, mowing, herbicide use, and deer browsing. Activities such as refuse dumping, dog walking, and all-terrain vehicle or dirt-bike use may also threaten the species.

As suitable habitat for Willowleaf Aster is limited and fragmented in Ontario, and the species’ range is situated in some of the most developed parts of the province, the distribution of the species in Ontario is unlikely to expand significantly. Recovery efforts for this species will focus on improving habitat and reducing threats at sites currently occupied by the species.

The government’s goal for the recovery of the Willowleaf Aster is to maintain populations and sub-populations at, or enable them to increase to, sustainable levels at sites where the species occurs in Ontario.

Protecting and recovering species at risk is a shared responsibility. No single agency or organization has the knowledge, authority or financial resources to protect and recover all of Ontario’s species at risk. Successful recovery requires inter-governmental co-operation and the involvement of many individuals, organizations, and communities.

In developing the government response statement, the Ministry considered what actions are feasible for the government to lead directly and what actions are feasible for the government to support its conservation partners to undertake.

Government-led actions

To help protect and recover Willowleaf Aster, the government will directly undertake the following actions:

  • Continue to implement the Ontario Invasive Species Strategic Plan to address the invasive species (e.g., Black Locust (Robinia pseudoacacia), Common Buckthorn (Rhamnus cathartica), etc.) that threaten Willowleaf Aster.
  • Educate other agencies and authorities involved in planning and environmental assessment processes on the protection requirements under the ESA.
  • Encourage the submission of Willowleaf Aster data to the Ministry’s central repository at the Natural Heritage Information Centre.
  • Undertake communications and outreach to increase public awareness of species at risk in Ontario.
  • Protect the Willowleaf Aster and its habitat through the ESA.
  • Support conservation, agency, municipal and industry partners, and Aboriginal communities and organizations to undertake activities to protect and recover the Willowleaf Aster. Support will be provided where appropriate through funding, agreements, permits with appropriate conditions, and/or advisory services.

Encourage collaboration, and establish and communicate annual priority actions for government support in order to reduce duplication of efforts.

Government-supported actions

The government endorses the following actions as being necessary for the protection and recovery of the Willowleaf Aster. Actions identified as High will be given priority consideration for funding under the ESA. Where reasonable, the government will also consider the priority assigned to these actions when reviewing and issuing authorizations under the Endangered Species Act. Other organizations are encouraged to consider these priorities when developing projects or mitigation plans related to species at risk. The government will focus its support on these high-priority actions over the next five years.

Focus Area: Protection and management

Objective: Maintain or improve habitat and reduce threats at sites where Willowleaf Aster occurs in Ontario.

Actions:
  1. (High) Develop and implement site-specific management strategies to manage and improve Willowleaf Aster habitat and reduce threats at sites where the species occurs, with consideration for other rare species and invasive species present on site. Monitor the effectiveness of actions taken and revise strategies, as appropriate, based on the best available information. This action includes providing support to Walpole Island First Nation in efforts to manage or improve habitat and reduce threats where the species occurs on the First Nation’s land.
    • Management strategies may include: controlled burning, removal of woody vegetation and invasive species, use of signage to discourage trampling by humans, dogs, and all-terrain vehicles, and other actions as appropriate.

Focus Area: Research and monitoring

Objective: Increase knowledge about Willowleaf Aster populations, successful reproduction, and historical occurrence in Ontario.

Actions:
  1. (High) Conduct surveys at all sites where the species is known to occur, suspected to occur, and at other sites with suitable habitat within the species’ distribution, to determine population status and assess threats. Surveys should be undertaken in the fall, when the species is in flower.
  2. Conduct research on factors influencing successful reproduction and dispersal of the species (e.g., pollination, seed set, seed germination rates, climate).
  3. Gather Aboriginal traditional knowledge and community knowledge about Willowleaf Aster, including historical populations, the past extent of the species’ habitat in Ontario, and the historical frequency of wildfire within the species’ habitat to inform habitat management best practices. Sources of information may include Aboriginal elders, Windsor homeowners, and farmers.

Focus Area: Awareness and stewardship

Objective: Increase awareness and stewardship of Willowleaf Aster and its habitat.

Actions:
  1. Promote awareness among landowners, land managers and land users, including Aboriginal communities and organizations, about Willowleaf Aster, including:
    • identification of the species;
    • the species’ habitat requirements;
    • protection afforded to the species and its habitat under the ESA; and,
    • actions they can take to help protect and recover the species.

Implementing actions

Financial support for the implementation of actions may be available through the Species at Risk Stewardship Fund, Species at Risk Research Fund for Ontario, or the Species at Risk Farm Incentive Program. Conservation partners are encouraged to discuss project proposals related to the actions in this response statement with the Ministry. The Ministry can also advise if any authorizations under the ESA or other legislation may be required to undertake the project.

Implementation of the actions may be subject to changing priorities across the multitude of species at risk, available resources and the capacity of partners to undertake recovery activities. Where appropriate, the implementation of actions for multiple species will be co- ordinated across government response statements.

Reviewing progress

The ESA requires the Ministry to conduct a review of progress towards protecting and recovering a species not later than five years from the publication of this response statement. The review will help identify if adjustments are needed to achieve the protection and recovery of Willowleaf Aster.

Acknowledgement

We would like to thank all those who participated in the development of the Recovery strategy for the Willowleaf Aster (Symphyotrichum praealtum) in Ontario for their dedication to protecting and recovering species at risk.

For additional information:

Visit the species at risk website
Contact your MNRF district office
Contact the Natural Resources Information Centre
1-800-667-1940
TTY: 1-866-686-6072
NRISC@ontario.ca
Ministry of Natural Resources and Forestry website