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Recovery Strategy for the Slender Bush-clover (Lespedeza virginica) in Canada – 2016 [Proposed]

Part 1

Federal Addition to the Recovery Strategy for the Slender Bush-clover (Lespedeza virginica) in Ontario, prepared by Environment Canada


The federal, provincial, and territorial government signatories under the Accord for the Protection of Species at Risk (1996) agreed to establish complementary legislation and programs that provide for effective protection of species at risk throughout Canada. Under the Species at Risk Act (S.C. 2002, c.29) (SARA), the federal competent ministers are responsible for the preparation of recovery strategies for listed Extirpated, Endangered, and Threatened species and are required to report on progress within five years after the publication of the final document on the SAR Public Registry.

The Minister of the Environment is the competent minister under SARA for the Slender Bush-clover and has prepared the federal component of this recovery strategy (Part 1), as per section 37 of SARA. SARA section 44 allows the Minister to adopt all or Part of an existing plan for the species if it meets the requirements under SARA for content (sub-sections 41(1) or (2)). The Ontario Ministry of Natural Resources (now the Ontario Ministry of Natural Resources and Forestry) led the development of the attached recovery strategy for the Slender Bush-clover (Part 2) in cooperation with Environment Canada. The Province of Ontario also led the development of the attached Government response (Part 3), which is the Ontario Governmnet’s policy response to its provincial recovery strategy and summarizes the prioritized actions that the Ontario government intends to take.

Success in the recovery of this species depends on the commitment and cooperation of many different constituencies that will be involved in implementing the directions set out in this strategy and will not be achieved by Environment Canada, or any other jurisdiction alone. All Canadians are invited to join in supporting and implementing this strategy for the benefit of the Slender Bush-clover and Canadian society as a whole.

This recovery strategy will be followed by one or more action plans that will provide information on recovery measures to be taken by Environment Canada and other jurisdictions and/or organizations involved in the conservation of the species. Implementation of this strategy is subject to appropriations, priorities, and budgetary constraints of the participating jurisdictions and organizations.

The recovery strategy sets the strategic direction to arrest or reverse the decline of the species, including identification of critical habitat to the extent possible. It provides all Canadians with information to help take action on species conservation. When the recovery strategy identifies critical habitat, there may be future regulatory implications, depending on where the critical habitat is identified. SARA requires that critical habitat identified within federal protected areas be described in the Canada Gazette, after which prohibitions against its destruction will apply. For critical habitat located on federal lands outside of federal protected areas, the Minister of the Environment must either make a statement on existing legal protection or make an order so that the prohibition against destruction of critical habitat applies.  For critical habitat located on non-federal lands, if the Minister of the Environment forms the opinion that any portion of critical habitat is not protected by provisions in or measures under SARA or other Acts of Parliament, and not effectively protected by the laws of the province or territory, SARA requires that the Minister recommend that the Governor in Council make an order to extend the prohibition against destruction of critical habitat to that portion.  The discretion to protect critical habitat on non-federal lands that is not otherwise protected rests with the Governor in Council.

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The initial draft of the federal addition was prepared by Holly Bickerton (Consulting Ecologist, Ottawa). Assistance from Judith Jones (Winter Spider Eco-consulting) is gratefully acknowledged. Fieldwork on this species in the past two decades has been undertaken by Sam Brinker (Ontario Ministry of Natural Resources and Forestry (OMNRF), Michael J. Oldham (Natural Heritage Information Centre, OMNRF), Karen Cedar (City of Windsor) and Paul Pratt (formerly City of Windsor), among others. Additional preparation and review of the document was completed by Ken Tuininga, Lauren Strybos, Krista Holmes, Marie-Claude Archambault and Marsha Jeffers-Smith (Environment Canada, Canadian Wildlife Service – Ontario) and Aileen Wheeldon (OMNRF)) and Michael J. Oldham (Natural Heritage Information Centre, OMNRF) reviewed and provided comments and advice during the development of this document. Amelia Argue (Ontario Ministry of Natural Resources and Forestry) provided additional information.

Acknowledgement and thanks is given to all other parties that provided advice and input used to help inform the development of this recovery strategy including various Aboriginal organizations and individuals, landowners, citizens and stakeholders who provided input and/or participated in consultation meetings.

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Additions and Modifications to the Adopted Document

The following sections have been included to address specific requirements of the federal Species at Risk Act (SARA) that are not addressed in the Province of Ontario’s Recovery Strategy for the Slender Bush-clover (Lespedeza virginica) in Ontario (Part 2) and to provide updated or additional information.

Under SARA, there are specific requirements and processes set out regarding the protection of critical habitat. Therefore, statements in the provincial recovery strategy referring to protection of survival/recovery habitat may not directly correspond to federal requirements. Recovery measures dealing with the protection of habitat are adopted; however, whether these measures will result in protection of critical habitat under SARA will be assessed following publication of the federal recovery strategy.

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1. COSEWICFootnote star * Species Assessment Information

Date of Assessment: May 2013

Common Name: Slender Bush-clover

Scientific Name: Lespedeza virginica

COSEWIC Status: Endangered

Reason for Designation:
This perennial species occupies small patches of remnant tallgrass prairie and savanna at just one location in southern Ontario, where it is at risk from the combined impacts of a lack of natural disturbance by periodic fires and the presence of invasive plant species. There is a continuing decline in the quality and area of habitat available for the plant.

Canadian Occurrence: Ontario

COSEWIC Status History:
Designated Endangered in April 1986. Status re-examined and confirmed Endangered in April 1999, May 2000, and May 2013.


Footnote star *

COSEWIC (Committee on the Status of Endangered Wildlife in Canada)

Return to footnote star *

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2. Species Status Information

Slender Bush-clover (Lespedeza virginica) is known from only a single extantFootnote 3population consisting of three sub-populations in the City of Windsor in southwestern Ontario. In North America its range extends from Michigan and southern Ontario to Texas and northern Florida.

Slender Bush-clover is listed as Endangered on Schedule 1 of the federal Species at Risk Act (SARA) and Endangered under the provincial Endangered Species Act, 2007 (ESA 2007).

Slender Bush-clover has a global conservation rank of SecureFootnote 4(G5). In Canada and Ontario, the species is ranked as Critically ImperilledFootnote 5 (N1, S1) (NatureServe 2014).  In the United States it is considered Secure (N5), and in 3 of the 32 states in which it is found it is considered Critically Imperiled to Vulnerable (S1-S3), or Presumed Extinct (SX), mainly those at the northern limit of its range (Appendix A). Less than one percent of the species’ global range occurs in Canada (COSEWIC 2013).

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3. Recovery Feasibility Summary

Based on the following four criteria that Environment Canada uses to establish recovery feasibility, there are unknowns regarding the feasibility of recovery of the Slender Bush-clover. In keeping with the precautionary principle, a recovery strategy has been prepared as per section 41(1) of SARA, as would be done when recovery is determined to be feasible. This recovery strategy addresses the unknowns surrounding the feasibility of recovery.

1. Individuals of the wildlife species that are capable of reproduction are available now or in the foreseeable future to sustain the population or improve its abundance.

Yes. In Canada, there is one population made up of three subpopulationsFootnote 6(Ojibway Park, Tallgrass Heritage Park and Black Oak Heritage Park) within the City of Windsor. As recently as August 2014, plants were observed flowering and fruiting in the tallgrass prairie habitat at Ojibway Park (Oldham pers. comm. 2015). Most of the plants observed were in fruit (COSEWIC 2013). Slender Bush-clover also occurs widely in dry, open habitats throughout the central and eastern United States, and in many of these areas it is considered secure (NatureServe 2014). The species has been documented from 17 counties in adjacent Michigan (Voss and Reznicek 2012).

2. Sufficient suitable habitat is available to support the species or could be made available through habitat management or restoration.

Unknown.  Slender Bush-clover is at the northern limit of its range in Canada, and has been reported only from Windsor and one other (extirpated) location near Leamington (COSEWIC 2013). It is likely that the species only ever occurred in very small numbers in Canada. Only 2.4 percent of the species suitable habitat type, tallgrass prairie, remains in all of North America today (Samson et al. 2004), with less than 1 percent remaining in Ontario (Bakowsky and Riley 1994; Catling and Brownell 1999; Catling 2008). The remaining suitable habitat in Canada that is known to be occupied by the Slender Bush-clover occurs in three small areas within the City of Windsor (Ojibway Prairie Complex), and these areas are succeeding to woody vegetation which is shading the habitat and making it less suitable. Although the habitat could be improved through restoration, other habitat has been irreversibly lost and it is not clear whether restoration would be sufficient to allow for a sustainable Canadian population over the long term.

3. The primary threats to the species or its habitat (including threats outside Canada) can be avoided or mitigated.

Unknown. The primary threats to the Slender Bush-clover include habitat degradation due to an altered disturbance regime (i.e., a lack of natural fire), and the increasing presence of invasive plant species, especially Autumn Olive (Elaeagnus umbellata), Crown Vetch (Securigera varia) and Spotted Knapweed (Centaurea stoebespp. micranthos) (Oldham pers. comm. 2015). Burning has occurred at all three Windsor sub-population locations at some point in the last three decades. Prescribed burns are undertaken periodically within the Ojibway Prairie, although the frequency and intensity of burns to date may be insufficient to maintain the conditions required for the Slender Bush-clover (Jones 2013). Although the impacts of invasive plant species may to some extent be controlled or mitigated through herbicide use or prescribed burning, their propagules are often abundant within urban areas and burning near urban areas must be carefully controlled to avoid damage to infrastructure or other assets. The effort required to mitigate the impacts of invasive plants on an urban prairie may be significant and ongoing in order to be successful.

4. Recovery techniques exist to achieve the population and distribution objectives or can be expected to be developed within a reasonable timeframe.

Unknown.  Several techniques are now widely used to restore tallgrass prairie habitats in southern Ontario, including prescribed burning and mowing (e.g., Rodger 1998). Slender Bush-clover is also frequently cultivated, is reportedly easy to grow, and has been successfully grown from seed at the Ojibway Nature Centre (COSEWIC 2003; Jones 2013). Successful control techniques have also been identified for many invasive plants; however, little information exists on the control of Crown Vetch (Southeastern Wisconsin Invasive Species Consortium 2014).

In Canada, the Slender Bush-clover has a very restricted distribution and is at the northern edge of the species’ range. The species has probably always been uncommon in Ontario (COSEWIC 2013), and will likely continue to be rare in Canada despite applying available recovery techniques and maintaining existing populations.

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4. Threats

In addition to the known and potential threats outlined in Part 2 - Recovery Strategy for the Slender Bush-clover (Lespedeza virginica) in Ontario, another potential threat to the Slender Bush-clover is the decline in pollinator populations. The primary pollinator of Ontario populations has not been identified, however, it is thought that the species is primarily pollinated by bees, moths, and butterflies (Pratt 1986). A number of factors are suspected to be contributing to the decline in insect pollinator populations globally and in Canada, including loss of habitat and food sources, diseases, viruses, pests, and pesticide exposure (Health Canada 2014). Notably, there is growing evidence to suggest that pesticides, including neonicotinoids, may be having negative effects on pollinator populations due to their toxic properties and persistence in soil and water (van der Sluijs et al. 2013; Cutler et al. 2014).Currently, the extent to which the decline of pollinator populations may impact the Slender Bush-clover is not known.

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5. Population and Distribution Objectives

The provincial Recovery Strategy for the Slender Bush-clover (Lespedeza virginica) in Ontario contains the following recovery goal:

  • The recovery goal is to maintain the abundance and distribution of growing plants  of the Slender Bush-clover at Ojibway Park at current or greater levels by reducing threats, and if the species is extant in the seed bank at the other two sub-populations, to increase the number of growing plants present there to pre-1995 levels.

The Government Response Statement for the Province of Ontario (Part 3) lists the following goal for the recovery of the Slender Bush-clover in Ontario:

  • The government’s goal for the recovery of the Slender Bush-clover in Ontario is to maintain the existing population at, or increase it to, a sustainable level at existing sites.

Under SARA, a population and distribution objective for the species must be established. The population and distribution objective established by Environment Canada for the Slender Bush-clover is to:

  • Maintain the existing population of the Slender Bush-clover and where biologically and technically feasible, increase the species’ abundance at existing sites.

Maintaining the existing population of the Slender Bush-clover is important since this single population constitutes the entire Canadian distribution. Plants have not been seen in two of the three Windsor sub-populations (i.e., Black Oak Heritage Park and Tallgrass Heritage Park sub-populations) over the last two decades, which is likely due to habitat degradation. Thus, maintaining the existing population for the foreseeable future may require on-going restoration (Jones 2013). This will include significant habitat management and restoration efforts, as well as invasive species control. Appropriate actions for each of the three sub-populations are being initiated (Jones pers. comm. 2015).

Even with active, ambitious, and dedicated habitat management and restoration activities, the long-term sustainability of this small population of only 165 plants is not known. Determining the population viability over the long-term is identified as a research need within the provincial recovery strategy (Jones 2013) and the Slender Bush-clover – Ontario Government Response Statement (Part 3). In addition, Environment Canada recognizes the role of cultivating and maintaining specimens at off-site locations for the purpose of supporting research on the feasibility and appropriateness of introducing or reintroducing the Slender Bush-clover at sites in Ojibway Park, Tallgrass Heritage Park and Black Oak Heritage Park (government-supported action #3 - Part 3). Reintroduction may play an important role in the recovery of the species where habitat is considered suitable and in improving the viability of the extant population.

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6. Broad Strategies and General Approaches to Meet Objectives

The government-led and government-supported actions tables from the Slender Bush-clover – Ontario Government Response Statement (Part 3) are adopted as the broad strategies and general approaches to meet the population and distribution objectives. Environment Canada is not adopting the approaches identified in section 2.3 of the Recovery Strategy for the Slender Bush-clover (Lespedeza virginica) in Ontario (Part 2).

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7. Critical Habitat

7.1 Identification of the Species’ Critical Habitat

Section 41 (1)(c) of SARA requires that recovery strategies include an identification of the species’ critical habitat, to the extent possible, as well as examples of activities that are likely to result in its destruction. Critical habitat is defined in the Species at Risk Act (S.C.2002, c29) section 2(1) as “the habitat that is necessary for the survival or recovery of a listed wildlife species and that is identified as the species’ critical habitat in the recovery strategy or in an action plan for the species”.

Identification of critical habitat is not a component of provincial recovery strategies under the Province of Ontario's ESA 2007. Under the ESA 2007, when a species becomes listed as endangered or threatened on the Species at Risk in Ontario List, it automatically receives general habitat protection. Slender Bush-clover currently receives general habitat protection under the ESA 2007; however, a description of the general habitat has not yet been developed. In some cases, a habitat regulation may be developed that replaces the general habitat protection. A habitat regulation is a legal instrument that prescribes an area that will be protectedFootnote 7 as the habitat of the species by the Province of Ontario. A habitat regulation has not been developed for the Slender Bush-clover under the ESA 2007; however, the provincial recovery strategy (Part 2) contains a recommendation on the area for consideration in developing a habitat regulation. This federal recovery strategy identifies critical habitat for the Slender Bush-clover in Canada to the extent possible, based on this recommendation and on the best available information as of November 2014.

Critical habitat is identified for the one extant population of the Slender Bush-clover, and is sufficient to meet the population and distribution objective. Critical habitat is not identified for horticultural specimens and plants that did not originate from the Slender Bush-clover plants native to Ontario or that were planted for purposes other than species recovery, ecological restoration/ rehabilitation or habitat creation, such as in landscaped settings and urban gardens. Additional critical habitat may be added in the future if  new or additional information supports the inclusion of areas beyond those currently identified (e.g., new sites become colonized or are found in adjacent areas).

The identification of critical habitat for the Slender Bush-clover is based on two criteria: habitat occupancy and habitat suitability.

7.1.1 Habitat Occupancy

This criterion refers to areas where there is a reasonable degree of certainty of current use by the species.
Habitat is considered occupied when:

  • there has been an observation of one or more native Slender Bush-clover individuals within the last 50 years.

Habitat occupancy is based on field surveys from Ontario’s Conservation Data Centre (Natural Heritage Information Centre - NHIC), COSEWIC (2013), and recent field surveys and imagery completed by Brinker and Oldham (2011) for the three sub-populations in the City of Windsor. These include Ojibway Park, Tallgrass Heritage Park and Black Oak Heritage Park (otherwise referred to as the Ojibway Prairie Complex). A precautionary approach of a period of 50 years was taken to include identifying the areas formerly occupied by the Slender Bush-clover where the seed bank may possibly persist and be viable as well as to include areas most suitable for recovery and restoration efforts. Seeds were successfully germinated from 54 year old herbarium samples (Clewell 1966b); however, it is unknown how long the seeds of the Slender Bush-clover can remain viable within the seed bank. For this reason, the absence of plants in any one year does not indicate the loss of the sub-population (COSEWIC 2013). While no plants have been seen at the Tallgrass Heritage Park and Black Oak Heritage Park sites in over ten years, they are treated as possibly extant based on the potential presence of a viable seed bank.

7.1.2 Habitat Suitability

Habitat suitability relates to areas possessing a specific set of biophysical attributes that can support individuals of the species in carrying out essential aspects of their life cycle.

In Canada, extant sub-populations of the Slender Bush-clover are found in the exposed (non-shaded), sandy soils of dry-mesic tallgrass prairie, savanna or woodland relics (COSEWIC 2013).

The biophysical attributes of suitable habitat for the Slender Bush-clover include:

  • Open and semi-open areas (≤ 60% tree cover) with patches of exposed sandy soils in full sun (for the establishment of seedlings)
    • Typically found in dry-mesic tallgrass prairie, savanna or woodland relics,  dominated by Black Oak (Quercus velutina)
    • Understory layer generally consists of prairie graminoids and forbs, Big Bluestem (Andropogon gerardii), Little Bluestem (Schizachyrium scoparium), Crown Vetch (Securigera varia), Canadian Tick-trefoil (Desmodium canadense), Feather Three-awn (Aristida purpurascens), Dense Blazing Star (Liatris spicata), Spotted Knapweed (Centaurea stoebe) and Indian Grass (Sorghastrum nutans)
  • Poorly drained sands (e.g., GranbyFootnote 8 series) with a depth of up to 1 m overlying impermeable clays
  • Neutral to slightly alkaline, limestone parent material

Based on the best available information, suitable habitat for the Slender Bush-clover is currently defined as the extent of the biophysical attributes where the Slender Bush-clover exists in Ontario. In addition to the suitable habitat, a critical function zone of 50 m (radial distance) is applied when the biophysical attributes around a plant extend for less than 50 m.

In Ontario, suitable habitat for the Slender Bush-clover can be described using the Ecological Land Classification (ELC) framework for Southern Ontario (Lee et al. 1998). The ELC framework provides a standardized approach to the interpretation and delineation of dynamic ecosystem boundaries. The ELC approach classifies habitats not only by vegetation community but also considers soil moisture conditions and topography, and as such provides a basis for describing the ecosystem requirements (e.g., local effects of the associated hydrologic regime, canopy cover) and encompasses the biophysical attributes of suitable habitat for the Slender Bush-clover. In addition, ELC terminology and methods are familiar to many land managers and conservation practitioners who have adopted this tool as the standard approach in Ontario.

Within the ELC system in Ontario, the ELC vegetation type boundary will capture the biophysical attributes required by the species. The vegetation type includes the areas occupied by the Slender Bush-clover and the surrounding areas that provide suitable habitat conditions to carry out essential life process for the species and should allow for natural processes related to population dynamics and reproduction (e.g., dispersal and pollination) to occur. Slender Bush-clover habitat specificity typically restricts its growth to specific microhabitat conditions found within small open patches. Therefore, using the vegetation type boundaries to delineate critical habitat boundaries would be a precautionary approach to protect the critical microhabitats as the area around the plant may promote ecosystem resilience to invasive species and their subsequent impacts on the critical microhabitat conditions. The additional area may also have restoration potential for the Slender Bush-clover due to the long-lived nature of its seed.

ELC vegetation types containing the Slender Bush-clover have been described in Ontario as Dry Black Oak Tallgrass Savanna or Dry Black Oak Tallgrass Woodland (Jones 2013) but may also include Dry Tallgrass Prairie. Additional habitat assessments are required to delineate and map the extent of specific ELC vegetation types currently occupied by the Slender Bush-clover.  

The 50 m distance of was considered as a minimum ‘critical function zone’, or the threshold habitat fragment size required for maintaining constituent microhabitat properties for a species (e.g. light, temperature, litter moisture, humidity levels necessary for survival) and which allows some natural processes to occur (e.g., hydrological, dispersal). At present, it is not clear at what distances physical and/or biological processes begin to negatively affect the Slender Bush-clover. Studies on micro-environmental gradients at habitat edges, i.e., light, temperature, litter moisture (Matlack 1993), and on edge effects of plants in mixed hardwood forests, as evidenced by changes in plant community structure and composition (Fraver 1994), have shown that edge effects could be detected up to 50 m into habitat fragments, although other studies show that the magnitude and distance of edge effects will vary depending on the structure and composition of adjacent habitat types (Harper et al. 2005). Forman and Alexander (1998) and Forman et al. (2003) found that most roadside edge effects on plants resulting from construction and repeated traffic have their greatest impact within the first 30 to 50 m. Therefore, a 50 m distance from any Slender Bush-clover plant is an appropriate minimum distance to ensure that microhabitats are maintained as part of the identification of critical habitat. The area within the critical function zone may include both suitable and unsuitable habitat as the Slender Bush-clover may be found near the transition area/zone between suitable and unsuitable habitat (e.g. within small forest openings, or along woodland edges). As new information on species’ habitat requirements and site-specific characteristics, become available, these distances may be refined.

7.1.3   Application of the Slender Bush-clover Critical Habitat Criteria

Critical habitat for the Slender Bush-clover is identified as the extent of suitable habitat (section 6.1.2) where the occupancy criterion (section 6.1.1) is met. In cases where the suitable habitat extends for less than 50 m around a Slender Bush-clover plant, a critical function zone capturing an area within a radial distance of 50 m is also included as critical habitat. In Ontario, as noted above, suitable habitat for the Slender Bush-clover is most appropriately identified as the ELC vegetation type. At the present time, the vegetation type boundaries are not available to support the identification of critical habitat for the population. In the interim, ELC community series level is identified as the area within which critical habitat is found. In Ontario, critical habitat is located within these boundaries where the biophysical attributes described in section 6.1.2 are found and where the occupancy criterion is met (section 6.1.1). When vegetation type boundaries are determined, the identification of critical habitat will be updated.

Application of the critical habitat criteria to the best available data identifies critical habitat for the three known sub-populations within the extant population of the Slender Bush-clover in Canada (Figure 1, See also Table 1), totalling up to 19 haFootnote 9. The critical habitat identified is considered a full identification of critical habitat, sufficient to meet the population and distribution objectives.

Critical habitat for the Slender Bush-clover is presented using 1 x 1 km UTM grid squares. The UTM grid squares presented in Figure 1 are part of a standardized grid system that indicates the general geographic areas containing critical habitat, which can be used for land use planning and/or environmental assessment purposes. In addition to providing these benefits, the 1 X 1 km UTM grid respects data-sharing agreements with the province of  Ontario. Critical habitat within each grid square is defined by the criteria established by the description of habitat occupancy (section 6.1.1) and habitat suitability (section 6.1.2). Any human-made structures and any area outside the critical function zone that does not correspond to the biophysical attributes of suitable habitat for the Slender Bush Clover (see section 6.1.2) are not considered critical habitat. More detailed information on critical habitat to support protection of the species and its habitat may be requested on a need-to-know basis by contacting Environment Canada – Canadian Wildlife Service at

Figure 1. Grid squares that contain critical habitat for the Slender Bush-clover in Canada. Critical habitat for the Slender Bush-clover occurs within these 1 x1 km standardized UTM grid squares (red squares), where the description of habitat occupancy (section 6.1.1) and habitat suitability (section 6.1.2) are met.

Map: Critical habitat for the Slender Bush-clover - Ojibway Prairie Complexe - Essex County Ontario.

Long description for Figure 1

Figure 1 shows the four 1x1 km grid squares where critical habitat for the Slender Bush-clover is found in Ontario. There is one grid square in Black Oak Heritage Park, two in Ojibway Park and one in Tallgrass Heritage Park

Table 1. Grid squares that contain critical habitat for the Slender Bush-clover in Canada.Critical habitat for the Slender Bush-clover occurs within these 1 x 1 km standardized UTM grid squares where the description of habitat occupancy (section 6.1.1) and habitat suitability (section 6.1.2) are met.
Sub-populationCritical Habitat Unit1 x 1 km Standardized UTM grid  square IDFootnote aProvince/TerritoryUTM Grid Square CoordinateFootnoteb
- Easting
UTM Grid Square CoordinateFootnote b
- Northing
Estimated area (ha) that contains critical habitatFootnote cLand tenureFootnote d
Black Oak Heritage ParkBlack Oak Heritage Park17TLG2871Ontario32700046810009Non-federal Land
Ojibway ParkOjibway Park 117TLG2880Ontario32800046810003Non-federal Land
Ojibway ParkOjibway Park 117TLG2881Ontario3280004681000[shared with 17TLG2880]Non-federal Land
Ojibway ParkOjibway Park 217TLG2881Ontario32800046810004Non-federal Land
Tallgrass Heritage ParkTallgrass Heritage Park17TLG2891Ontario32900046810003Non-federal Land
  4 grid squares   ~19 ha 

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Table 1 Part 1 Footnotes

Footnote a

Based on the standard UTM Military Grid Reference System, where the first 2 digits and letter represent the UTM Zone, the following 2 letters indicate the 100 x 100 km standardized UTM grid followed by 2 digits to represent the 10 x 10 km standardized UTM grid. The last 2 digits represent the 1 x 1 km standardized UTM grid containing all or a portion of the critical habitat unit. This unique alphanumeric code is based on the methodology produced from the Breeding Bird Atlases of Canada (Visit the Bird Studies Canada Website for more information on breeding bird atlases).

Return to footnote a

Footnote b

The listed coordinates are a cartographic representation of where critical habitat can be found, presented as the southwest corner of the 1 x 1 km standardized UTM grid square containing all or a portion of the critical habitat unit. The coordinates may not fall within critical habitat and are provided as a general location only.

Return to footnote b

Footnote c

The area presented is that of the units containing critical habitat (rounded up to the nearest 1 ha); therefore, the actual area of critical habitat may be significantly less. Refer to Section 5.0 for a description of how critical habitat within these areas is defined.

Return to footnote c

Footnote d

Land tenure is provided as an approximation of the types of land ownership that exist at the critical habitat units and should be used for guidance purposes only. Accurate land tenure will require cross referencing critical habitat boundaries with surveyed land parcel information.

Return to footnote d

7. 2 Activities Likely to Result in the Destruction of Critical Habitat

Understanding what constitutes destruction of critical habitat is necessary for the protection and management of critical habitat. Destruction is determined on a case by case basis. Destruction would result if part of the critical habitat was degraded, either permanently or temporarily, such that it would not serve its function when needed by the species. Destruction may result from a single activity or multiple activities at one point in time or from the cumulative effects of one or more activities over time (Government of Canada 2009).

It should be noted that not all activities that occur in or near critical habitat are likely to cause its destruction. Activities described in Table 2 are examples of those likely to cause destruction of critical habitat for the species; however, destructive activities are not necessarily limited to those listed.

Table 2. Activities Likely to Destroy Critical Habitat of the Slender Bush-clover
Description of ActivityDescriptions of Effect in Relation to Function LossDetails of Effect
Any activity that results in changes to natural disturbance regimes (e.g., fire suppression).Natural disturbances, which remove woody or competing vegetation and thatch are essential to the Slender Bush-clover as it requires open ground habitat for germination and growth and cannot compete with surrounding vegetation.
As the Slender Bush-clover seedlings require relatively open habitats for establishment, plants are unable to reproduce or survive for more than a few years unless habitat remains open through either fire or some other disturbance. When this activity occurs within or adjacent to critical habitat at any time of year, it can result in habitat degradation or loss of critical habitat due to increased cover; which in turn can ultimately lead to a complete decline and loss of the population.
Activities that introduce exotic plants (e.g., introduction of non-native plant seeds, plants, foreign soil or gravel, composting or dumping of garden waste)Introducing invasive species can result in competition with the species, and/or physical and chemical changes to habitat such that it is no longer suitable for the species.Introduction of exotic invasive plants within or immediately adjacent to critical habitat at any time of year can result in destruction of critical habitat. The introduction of exotic invasive plants can lead to the gradual destruction of critical habitat over time.
Development and conversion of lands that results in the clearing of natural vegetation communities (e.g.,  residential and commercial development and road construction)Conversion of habitat results in a direct loss of critical habitat which the species relies on for basic survival, successful seed production, development, and establishment.

If these activities were to occur within critical habitat, the effects would be direct and would apply at any time of year. These activities would directly remove substrate and/or alter conditions (vegetation cover type and soil type) that allow for the establishment, germination and dispersal of the Slender Bush-clover.

If this activity were to occur outside of critical habitat it may have an indirect impact on microhabitat characteristics (such as hydrology).

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8. Measuring Progress

The performance indicators presented below provide a way to define and measure progress toward achieving the population and distribution objectives. Every five years, success of recovery strategy implementation will be measured against the following performance indicator:

  • The existing population has been maintained and where biologically and technically its abundance increased at existing sites.

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9. Statement on Action Plans

One or more action plans will be completed for the Slender Bush-clover and posted on the Species at Risk Public Registry by December 31, 2023.

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10. Effects on the Environment and Other Species

A strategic environmental assessment (SEA) is conducted on all SARA recovery planning documents, in accordance with the Cabinet Directive on the Environmental Assessment of Policy, Plan and Program Proposals. The purpose of a SEA is to incorporate environmental considerations into the development of public policies, plans, and program proposals to support environmentally sound decision-making and to evaluate whether the outcomes of a recovery planning document could affect any component of the environment or any of the Federal Sustainable Development Strategy’s (FSDS) goals and targets.

Recovery planning is intended to benefit species at risk and biodiversity in general. However, it is recognized that strategies may also inadvertently lead to environmental effects beyond the intended benefits. The planning process based on national guidelines directly incorporates consideration of all environmental effects, with a particular focus on possible impacts upon non-target species or habitats. The results of the SEA are incorporated directly into the strategy itself, but are also summarized below in this statement.

Slender Bush-clover inhabits provincially rare vegetation communities in Ontario. At its single remaining population, it grows with a number of other at-risk and provincially significant plants, including Dense Blazing Star (Liatris spicata, THR), Arrow Feather Three-awn (Aristida purpurascens, S1), Tall Coreopsis (Coreopsis tripteris, S2) and Round-fruited Panic Grass (Dichanthelium sphaerocarpon, S3) (COSEWIC 2013). Other provincially and nationally significant plant species growing in the vicinity of the extant sub-population of the Slender Bush-clover at Ojibway Park include Yellow Wild Indigo (Baptisia tinctoria, S2), Spotted Wintergreen (Chimaphila maculata, S1, END), Ohio Spiderwort (Tradescantia ohiensis, S2), Sundial Lupine (Lupinus perennis, S3) and Field Thistle (Cirsium discolor, S3).

Most other species present are adapted to open prairie and savanna habitats, and are considered to benefit from management activities similar to those identified for the Slender Bush-clover, including burning, vegetation clearing, soil scraping, or raking. Staff at the Ojibway Nature Centre (City of Windsor) are already taking measures to protect fire-sensitive species during prescribed burns (Jones 2013). The management activities undertaken may limit the spread of aggressive invasive species, which threaten other significant species in the provincially rare vegetation communities occupied by the Slender Bush-clover. The provincial recovery strategy identifies a need to consider the potential actions of both habitat management and invasive species removal on other rare species present in similar habitat (Jones 2013).

The potential for this recovery strategy to inadvertently lead to adverse effects on other species was considered. The SEA concluded that this strategy will clearly benefit the environment and will not entail significant adverse effects.

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Bakowsky, W. D., and J. L. Riley. 1994. A survey of the prairies and savannas of southern Ontario. Pages 7–16 in Proceedings of the 13th North American Prairie Conference. R.G. Wickett, P.D. Lewis, A. Woodliffe, and P. Pratt (eds.). Windsor, Ontario: Corporation of the City of Windsor.

Brinker, S.R. and M.J. Oldham. 2011. Summary of 2011 Ontario Field Surveys for Slender Bush-clover (Lespedeza virginica) October 31, 2011. Natural Heritage Information Centre, Ontario Ministry of Natural Resources, Peterborough Ontario. 9 pp.

Catling, P.M. 2008. The extent and floristic composition of the Rice Lake Plains based on remnants. Canadian Field-Naturalist 122:1-20.

Catling, P.M. and V.R. Brownell. 1999. Additional notes on the vegetation of dry openings along the Trent River, Ontario. Canadian Field-Naturalist 113:506-509.

COSEWIC. 2003. COSEWIC assessment and status report on the Slender Bush-clover Lespedeza virginica in Canada. vi+16 pp. Committee on the Status of Endangered Wildlife in Canada, Ottawa, Ontario.

COSEWIC. 2013. COSEWIC assessment and status report on the Slender Bush-clover Lespedeza virginica in Canada. x + 31 pp. Committee on the Status of Endangered Wildlife in Canada, Ottawa, Ontario.

Clewell, A. F. 1966. Natural History, Cytology, and Isolating Mechanisms of the Native American Lespedezas. Bulletin of Tall Timbers Research Station. Tall Timbers Research Station, Tallahassee, Florida.

Cutler, G.C., C.D. Scott-Dupree, and D.M. Drexler. 2014. Honey bees, neonicotinoids, and bee incident reports: the Canadian situation. Pest Management Science 70(5): 779-783.

Fraver, S. 1994. Vegetation responses along edge-to-interior gradients in the mixed hardwood forests of the Roanoke River Basin, North Carolina. Conserv. Biol. 8(3): 822-832.

Forman, R.T.T. and L.E. Alexander. 1998. Roads and Their Major Ecological Effects. Annual Review of Ecology and Systematics, 29: 207-231.

Forman, R. T. T., D. Sperling, J. A. Bissonette, A. P. Clevenger, C. D. Cutshall, V. H. Dale, L. Fahrig, R. France, C. R. Goldman, K. Heanue, J. A. Jones, F. J. Swanson, T. Turrentine, and T. C. Winter. 2003. Road Ecology. Science and Solutions. Island Press, Washington, D.C., USA. 481 pp.

Government of Canada. 2009.  Species at Risk ActPolicies, Overarching Policy Framework [Draft]. Species at Risk Act Policy and Guidelines Series. Environment Canada. Ottawa. 38 pp.

Harper K. A., S.E. Macdonald, P. J.  Burton , J. Chen , K. D. Brosofske , S.C. Saunders, E.S. Euskirchen, D. Roberts,  M.S Jaiteh, P.A Esseen 2005.  Edge influence on forest structure and composition in fragmented landscapes. Conservation Biology 19:768–782.

Health Canada. 2014. Pollinator Health and Pesticides. [Visited: 14 November 2014]

Jones, J. 2013. Recovery Strategy for the Slender Bush-clover (Lespedeza virginica) in Ontario. Ontario Ministry of Natural Resources, Peterborough, Ontario. vi + 26 pp.

Jones, J., pers. comm. 2015.  Email correspondence to K. Tuininga. March 2015. Botanist, Winter Spider Eco-Consulting, Manitowaning, Ontario.

Lee, H. T., W. D. Bakowsky, J. Riley, J. Bowles, M. Puddister, P. Uhlig, and S. McMurray. 1998. Ecological Land Classification for Southern Ontario: First Approximation and Its Application. Ontario Ministry of Natural Resources, South Central Science Section, Science Development and Transfer Branch.

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NatureServe. 2002. Element Occurrence Data Standards. NatureServe. Arlington, Virginia. 147 pp.

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Pratt, P.D. 1986. Status report on Slender Bush-clover Lespedeza virginica (L.) Britt. (Fabaceace). Committee on the Status of Endangered Wildlife in Canada. Ottawa. vii + 23 pp.

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Appendix A: Subnational Conservation Ranks of the Slender Bush-Clover (Lespedeza virginica) in Canada and the United States

Slender Bush-clover (Lespedeza virginica)
Global (G) RankNational (N) Rank (Canada)Sub-national (S) Rank (Canada)National (N) Rank (United States)Sub-national (S) Rank
(United States)
G5N1Ontario (S1)N5Alabama (SNR), Arkansas (SNR), Connecticut (SNR), Delaware (S5), District of Columbia (SNR), Florida (SNR), Georgia (SNR), Illinois (SNR), Indiana (SNR), Iowa (S4), Kansas (SNR), Kentucky (S5), Louisiana (SNR), Maryland (SNR), Massachusetts (SNR), Michigan (SNR), Mississippi (SNR), Missouri (SNR), New Hampshire (S1), New Jersey (S5), New York (S3?), North Carolina (S5), Ohio (SNR), Oklahoma (SNR), Pennsylvania (SNR), Rhode Island (SNR), South Carolina (SNR), Tennessee (SNR), Texas (SNR), Virginia (S4), West Virginia (S4), Wisconsin (S2)

(NatureServe 2014)
Rank Definitions (NatureServe 2014)

N1/S1: Critically Imperilled (National/State) – At very high risk of extirpation in the jurisdiction (i.e., N - nation, or S -state/province) due to very restricted range, very few populations or occurrences, very steep declines, severe threats, or other factors.

S2: Imperilled (State) – At high risk of extirpation in the jurisdiction due to restricted range, few populations or occurrences, steep declines, severe threats, or other factors.

S3: Vulnerable (State) –  At moderate risk of extirpation in the jurisdiction due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats or other factors.

S4: Apparently Secure (State) – At a fairly low risk of extirpation in the jurisdiction due to an extensive range and/or many populations or occurrences but with possible cause for some concern as a result of local recent declines, threats or other factors.

G5/N5/S5: Secure (Glabal/National/State) – At very low risk of extinction or elimination due to a very extensive range, abundant populations or occurrences, and little to no concern from declines or threats.

SNR: Unranked – National or subnational conservation status not yet assessed.

Question mark (?) – Denotes an inexact numeric rank.

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Footnote 3

A population which is still in existence.

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Footnote 4

Globally Secure (G5): At very low risk of extinction or elimination due to a very extensive range, abundant populations or occurences, and little to no concern from delines or threats.

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Footnote 5

Nationally and provincially Critically Imperilled (N1,S1): At very high risk of extirpation in the jurisdiction due to very restricted range, very few populations or occurences, very steep declines, severe threats, or other factors.

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Footnote 6

Follows the NatureServe (2002) and the Natural Heritage Information Centre (NHIC) methods for defining populations of vascular plants - Groups of plants separated from each other by more than 1 km are considered separate populations; groups of plants that are less than 1 km apart from one another are considered subpopulations of a single population. Throughout this document, the term “population” is considered to be synonymous with the term “element occurrence” as used by the NHIC and NatureServe

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Footnote 7

Under the federal SARA, there are specific requirements and processes set out regarding the protection of critical habitat.  Protection of critical habitat under SARA will be assessed following publication of the final federal recovery strategy

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Footnote 8

The Granby series consists of poorly drained and very poorly drained soils that occur both on plains and uplands.

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Footnote 9

This is the maximum potential extent of critical habitat based on suitable habitat boundaries that can be delineated from high resolution aerial photography (comparable to the ELC community series) and/or a 50m radial distance around the Slender Bush-clover. Actual critical habitat occurs only in those areas described in section 6.1 and therefore the actual area could be less than this and would require field verification to determine the precise amount.

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