Slender Bush-clover

Species information

The following is a report on progress made towards the protection and recovery of Slender Bush-clover (Lespedeza virginica) in Ontario, from 2007 to 2018, based on species-specific policy. This meets the legislative requirement for a review of progress under the Endangered Species Act, 2007 (ESA or “the Act”). Slender Bush-clover is listed as endangered on the Species at Risk in Ontario (SARO) List under the ESA.

Slender Bush-clover has been classified as a species at risk in Ontario, since 2004. It was originally classified as an endangered species, and retained its ‘endangered’ status under the ESA, when it came into force in 2008.

The species-specific policy for Slender Bush-clover, known as the Government Response Statement (GRS), was developed in 2014, and includes the government’s recovery goal for the species and the actions and priorities it leads or supports to help achieve that goal. The GRS considers science advice provided in the recovery strategy when developing recovery actions for the species. As legislated in the Act, the purpose of the Review is to report on progress made towards implementing of the protection and recovery actions in the GRS. The Review can also help identify opportunities to adjust and adapt the implementation of protection and recovery actions to achieve the recovery goal for the species.

Further information about the species, including the threats that it faces and actions being taken to help protect and recovery this species, is available on Government of Ontario webpage for Slender Bush-clover. A summary of progress made towards the protection and recovery of Slender Bush-clover, and an annual update on the species at risk program, are available on the Review of Progress towards the Protection and Recovery of Ontario’s Species at Risk webpage.

Snapshot

Progress towards the protection and recovery of Slender Bush-clover

• The recovery goal in the Government Response Statement (GRS) for Slender Bush-clover in Ontario is to maintain the population at, or increase it to, a sustainable level at existing sites.
• Progress has been made towards implementing all government-led actions. Progress has also been made towards achieving all government-supported recovery objectives, and implementing several of the associated actions. Examples of progress include:
  • Surveying for Slender Bush-clover and inventorying to determine patch size
  • Removing invasive species and native woody vegetation at occupied sites
  • Prescribed burning at occupied sites to improve habitat suitability for Slender Bush-clover
• In alignment with the GRS, work on the following action has yet to be undertaken – determine the viability and condition of the population at Ojibway Park and whether viable seed remains at Tallgrass Heritage Park and Black Oak Heritage Park. Research is also needed to evaluate opportunities to establish or re-establish the species in existing suitable habitat within the Ojibway Prairie Complex.

Occurrence and distribution

• Two populations^{footnote 1[1]} of Slender Bush-clover have been documented in southwestern Ontario, of which one is extant, and the other is considered extirpated because it has not been recorded since 1892. No populations of Slender Bush-clover have been newly identified since 2008, but recent surveys have re-confirmed the extant population.

Government-supported stewardship projects

• Through the Species at Risk Stewardship Program, the Government of Ontario has enabled its stewardship partners to five projects ($117,507) that have supported the protection and recovery of multiple species at risk, including Slender Bush-clover.
• The government’s support helped its stewardship partners to involve 10 individuals who volunteered 619 hours of their time towards protection and recovery activities for species at risk, including Slender Bush-clover. The estimated value of these voluntary contributions, as well as additional funding and in-kind support, is $93,582.
• Stewardship partners reported that through their actions 13 hectares of habitat were enhanced for Slender Bush-clover and other species at risk that inhabit the same ecosystem.

Supporting human activities while ensuring appropriate support for species recovery

• One activity has been registered for the species, under the ‘Species protection and recovery activities’ section (section 23.17) of Ontario Regulation 242/08, under the ESA.

Reporting on progress towards the protection and recovery of Slender Bush-clover

The implementation of government-led and government-supported actions demonstrates progress towards reaching the desired objectives and the recovery goal set out in the GRS.

Progress towards implementing government-led actions

Progress has been made towards implementing all government-led actions. Common actions for the government to lead as it works toward achieving a species’ recovery goal include:

• Educate other agencies and authorities involved in planning and environmental assessment processes on the protection requirements under the ESA.
• Encourage the submission of Slender Bush-clover data to the central repository at the Natural Heritage Information Centre (NHIC).
• Undertake communications and outreach to increase public awareness of species at risk in Ontario.
• Protect the Slender Bush-clover and its habitat through the ESA.
• Support conservation, agency, municipal and industry partners, and Indigenous communities and organizations to undertake activities to protect and recover the Slender Bush-clover. 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.

Additionally, the government has directly undertaken the following species-specific action:

• Continue to implement the Ontario Invasive Species Strategic Plan to address the invasive species (for example, Crown Vetch (Securigera varia)) that threaten Slender Bush-clover.

Key progress made towards the implementation of these actions is described in the following sections.

Occurrence and distribution

Two populations^{footnote 1[1]} of Slender Bush-clover have been documented in Ontario. One is considered extant (i.e., observed within the last 20 years), and is located in the Windsor area at three sites – Ojibway Park, Tallgrass Heritage Park, and Black Oak Heritage Park. The other population, from Leamington, has not been recorded since 1892, and is considered extirpated from this site.

Since 2008, the government’s central repository at the Natural Heritage Information Centre (NHIC) has received approximately 22 records of the species, based on observations between 1914 and 2018, from a variety of sources. Records submitted have helped to refine where the species is known and has been known to occur and have provided additional information on the species’ habitat and threats.

Recent surveys since 2008 have re-confirmed the species’ presence at the Ojibway Park site. Twenty to 30 flowering and fruiting stems were reported in 2014, and 165 fruiting stems were observed in 2011. Surveys suggest that a stable population exists at this site and that prescribed burns and woody invasive species control in the area has resulted in an increase in plant numbers and vigour. Additional survey efforts in 2011 at the Tallgrass Heritage Park and Black Oak Heritage Park sites failed to find any individuals. Although no individuals have been seen at these sites for over 20 years, a viable seedbank may still exist because seeds obtained from specimens preserved in an herbarium for 54 years were successfully germinated (Clewell 1966).

It is possible that there are observations of Slender Bush-clover that have not been submitted to the government. Encouraging the submission of observations of this species is included in the GRS as a government-led action. The submission of species observations increases our knowledge of where they occur, and can play an important role in assessing the viability^{footnote 2[2]} of species populations.

Everyone is encouraged, or may be required by an authorization or approval, to submit observations of Slender Bush-clover, and any other species at risk observed, to the NHIC for incorporation into the provincial record of observations. Observations may now be submitted to NHIC via the Rare Species of Ontario project in iNaturalist.

• 22
  observations of this species were submitted to the NHIC since 2008

Government-supported stewardship projects

An important government-led action in the GRS for Slender Bush-clover is to support partners to undertake activities to protect and recover the species. Through the Species at Risk Stewardship Program the government has supported five projects ($117,507) designed to contribute to the protection and recovery of Slender Bush-clover. All of these projects focused on multiple species at risk, including Slender Bush-clover. In addition to government funding, partners reported they were successful in securing funding and in-kind support ($93,582) from other sources, which includes time and expertise provided by volunteers.

Stewardship partners reported that provincial funding helped them to secure in-kind support by involving 10 individuals who volunteered 619 hours of their time towards protection and recovery activities for multiple species at risk, including Slender Bush-clover, which has an estimated value of $29,180. Partners reported that through both their efforts and those of their volunteers, to implement actions contained in the GRS, they were successful in enhancing 13 hectares of habitat that will benefit multiple species at risk, including Slender Bush-clover.

The remainder of this section highlights one project supported through the Species at Risk Stewardship Program.

From 2015 to 2017, Tallgrass Ontario implemented a habitat management project for Slender Bush-clover, and other prairie species at risk, at the Ojibway Prairie Complex near Windsor, Ontario. The project was a collaboration of all Windsor-LaSalle jurisdictions that manage prairie habitat, including Tallgrass Ontario and project volunteers. This work was conducted by biologists, field assistants, land managers, technicians from the various jurisdictions, and supervised volunteers familiar with the Ojibway prairie ecosystem.

Locations where the species is known to occur were surveyed, to determine patch sizes prior to undertaking invasive plant removal. Surveyors found Slender Bush-clover in Ojibway Park, but not in Tallgrass Prairie Heritage Park. Volunteers undertook site-specific management planning prior to the removal of competing vegetation, to assist the growth of Slender Bush-clover and other species at risk plants, such as Colicroot (Aletris farinosa). Invasive woody species were removed with clippers, hand-saws and brush cutters (by trained volunteers) in the winter months, followed by a prescribed burn by qualified personnel in the spring.

After the prescribed burn in Ojibway Park in 2016, follow-up surveys showed an outstanding response with at least 200 non-flowering stems recorded and the area of occupancy tripled. Based on these results, the decision to initiate work in Tallgrass Prairie Heritage Park, where Slender Bush-clover had been recorded in the 1990s, was taken. Work crews implemented measures to avoid trampling species at risk plants by flagging areas where plants had been observed, and scheduling the timing of activities to avoid impacts to snakes and other species at risk. This project contributed to implementing the high priority GRS action to develop and implement plans for improving habitat conditions and managing invasive species and native woody vegetation at occupied sites.

Species at Risk Stewardship Program

• 
  5

  projects included Slender Bush-clover

• 
  $117,507

  for multi-species projects that included Slender Bush-clover

• 
  $93,582

  in additional funding and in-kind support

• 
  10

  volunteers

• 
  619

  volunteer hours

• 
  13

  hectares of habitat enhanced

Supporting human activities while ensuring appropriate support for species recovery

Supporting partners through permits and their associated conditions is an important government-led action. To date, no permits have been issued for Slender Bush-clover.

One activity that may affect Slender Bush-clover or its habitat has been registered under the ‘Species protection, recovery activities’ section (23.17) of Ontario Regulation 242/08 under the ESA. The registration required the registered individual to comply with all conditions of the Regulation, such as preparing a mitigation plan using best available information on steps that may help minimize or avoid adverse effects on the species; reporting observations of the species using the Ontario Species at Risk Observation Reporting Form and submitting it to the Natural Heritage Information Centre (NHIC); and, monitoring the effectiveness of steps taken to minimize adverse effects on each species.

• 1
  registration

Progress towards implementing government-supported actions

Government-supported actions are organized under overarching recovery objectives. Progress has been made towards achieving all government-supported recovery objectives, and implementing several of the associated actions that are identified in the GRS for Slender Bush-clover.

Under this objective, considerable progress has been made towards Action No. 1, through a project supported by the Species at Risk Stewardship Program. As part of a multi-year project to improve habitat conditions for Slender Bush-clover in the Ojibway Prairie Complex, a stewardship partner removed invasive species and woody vegetation, and conducted prescribed burns. The effectiveness of the actions taken at Ojibway Park were monitored, and the results informed subsequent habitat management at Tallgrass Prairie Heritage Park.

Under this objective, progress has been made towards Action No. 4 through a project supported by the Species at Risk Stewardship Program. Surveys for Slender Bush-clover were completed at Ojibway Park, Tallgrass Heritage Park and Black Oak Heritage Park, but the species was only found at Ojibway Park. Data on the number of individual plants was collected.

Further, initial progress towards Action No. 5 has been made through another project supported by the Species at Risk Stewardship Program. A study to improve our understanding of fire behaviour in tallgrass prairie prescribed burns was conducted. Grass samples were collected for determining fuel load and heat of combustion in a laboratory setting, and fire and weather observations were recorded during six prescribed burns to analyse fire intensity.

Summary of progress towards meeting the recovery goal

The recovery goal for Slender Bush-clover is to maintain the population at, or increase it to, a sustainable level at existing sites. Effort made towards implementing government-led and government-supported actions has contributed to progress towards this goal. The provincial record of observations indicates that Slender Bush-clover population levels are being maintained at Ojibway Park, and that habitat management efforts have supported an increase in the numbers of individual plants. Government-supported efforts have helped to protect and manage Slender Bush-clover habitat through the removal of invasive species and prescribed burning.

Recommendations

As stated in the GRS, this Review of Progress can be used to help identify whether adjustments to the implementation of GRS actions are needed, to achieve the protection and recovery of the species. Based on progress to date, the overall direction provided in the GRS for Slender Bush-clover, particularly the implementation of actions identified as high priority, should continue to guide protection and recovery of the species.

Although varying levels of progress have been made towards implementing all of the GRS actions for Slender Bush-clover, further work is needed to fully implement these actions and contribute to the ongoing protection and recovery of this species. For example, although initial progress has been made towards assessing the condition and viability of the population and habitat conditions within the Ojibway Prairie Complex (Action No. 4 – High Priority), further work is required to fully implement this action. Surveys are needed to determine whether there are viable Slender Bush-clover seed banks at Tallgrass Heritage Park and Black Oak Heritage Park. Research to assess the condition and viability of the population at Ojibway Park is needed, as well as evaluation of the severity of the threats at this location. Similarly, while studies of tallgrass prairie fuel loads have contributed to implementing Action No. 5, further research is necessary to determine the optimal frequency and intensity of prescribed burns, specifically for Slender Bush-clover. Studies of the effectiveness of other habitat management techniques, the genetic diversity of Slender Bush-clover in Ontario, seed and pollen dispersal rates, approaches to germination and recruitment, and the reproductive biology of the species are also needed to support the species’ recovery.

Relative to actions that have received a higher level of implementation, the following actions have received less implementation, and may be prioritized in future work towards the protection and recovery of the species:

Protecting and recovering Slender Bush-clover will continue to be a shared responsibility that will require the involvement of many individuals, organizations and communities. Financial support for the implementation of actions may be available through the Species at Risk Stewardship Program. The government can also advise if any authorizations under the ESA or other legislation may be required to undertake a project. By working together, we can continue to make progress towards protecting and recovering Slender Bush-clover in Ontario.

References

Clewell, A.F. 1966. Native North American species of Lespedeza (Leguminosae). Rhodora v. 68 pp. 359–405.