Rubus stipulatus (State Endangered) Recovery Plan

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Recovery Criteria | Population Status Assessment | Threat Assessment | Conservation Actions | Information Needs

Recovery Criteria for Rubus stipulatus 

Recovery criteria were developed based on three core conservation principles: redundancy, resiliency and representation (Shaffer and Stein 2000, Wolf et al. 2015). The three Rs provide a framework for ensuring a species is able to adapt and persist over time. These principles were assessed and criteria developed that are compatible with the NatureServe Conservation Status Assessment methodology (Faber-Langendoen et al., 2012; Master et al., 2012). A species is considered recovered only when all recovery criteria are met independently.

Redundancy

Redundancy is the ability of the species to withstand catastrophic events.

Criteria Currently Met

Redundancy is measured in two ways. The first measure is the number of persistent EOs (EOs ranks A-CD) for R. stipulatus in the MN DNR’s Natural Heritage Information System (NHIS). The second is the total range extent calculated as the area (in Kilometers squared) of the minimum convex polygon encompassing persistent EOs.

Criteria:There will be a minimum of 21 persistent populations (EOs ranked A-CD) of R. stipulatus in Minnesota with a range extent of at least 5,000 km2.

Status: As of 2026, there were 25 persistent populations in Minnesota with a range extent of 19,937 km2. The number of EOs and their range extent currently meet the redundancy criteria for R. stipulatus. An additional 10 EOs ranked E lack adequate in-field documentation of their status and may contribute additional redundancy upon further assessment.

Resiliency

Resiliency is defined as the ability of a population to withstand (i.e. fluctuate in size from year-to-year with no overall decline) natural stochasticity or human induced disturbance events.

Criteria NOT Currently Met

Resiliency was measured as the number of viable populations of R. stipulatus (EO ranks A-B)with evidence that current conditions are unlikely to change. Population viability was assessed based on population size, habitat conditions, and landscape context and evidence of stable conditions including population trends, and suitable habitat management and land protection.

Criteria: There will be at a minimum of 13 viable populations of R. stipulatus with evidence that the population size is stable or increasing size, and that land protection and management is consistent with the species needs. 

Status: As of 2026, there were only five viable populations in Minnesota (all B ranked). Three populations have no priory surveys documented in the NHIS. The two with prior surveys have no prior EO rank information. Two populations are protected, two have informal protection and one has no protection. Habitat management is unknown or not occurring in all five.

Representation

Representationis defined as the ability of a species to adapt to changing conditions.Representation can be indicated by ecological or genetic diversity.

Criteria NOT Currently Met

The criteria for representation were set to ensure persistent populations exist, and their genetic diversity is safe-guarded across the species’ entire distribution at the Ecological Subsection level. 

Criteria:

1) No current ecological diversity will be lost from Minnesota. This criterion was measured as presence of a persistent population of Rubus stipulatus (EO rank A-CD) within each of the eight Ecological Subsections in Minnesota where it occurs. 

2) Range-wide genetic diversity of Rubus stipulatus will be permanently safe-guarded. This criterion requires genetic preservation (e.g., conservation seed banking) meeting the minimum standards outlined by the Center of Plant Conservation from each of those Ecological Subsections.

Status: As of 2026, there are persistent populations in six of the Ecological Subsections encompassing R. stipulatus’ known distribution. There are 18 persistent populations in the Anoka Sand Plain. The other five Ecological Subsections contain only one or two persistent populations each (Chippewa Plains, Oak Savanna, St.Paul-Baldwin Plains, Mille Lacs Uplands and the Pine Moraines & Outwash Plains). 

As of 2025, The Plant Conservation Program of University of Minnesota Landscape Arboretum holds 129 R. stipulatus seeds.

Read more about the methods used to assess the status of R. stipulatus and develop recovery criteria

Population (EO) Assessment Metrics

The viability of each Rubus stipulatus population was assessed based on population size, habitat condition, and landscape context as described below. These factors were then incorporated into the population’s EO Rank.

Population Size: Population size for R. stipulatus was estimated as the number of genetic individuals (genets). A genet is as a genetically distinct individual arising from a single root crown consisting of at least two stems (ramets), also called canes. Two factors make estimating population size for this species challenging. First, R. stipulatus tends to co-occur with other Rubus species. While R. stipulatus is distinctly identifiable, congeners are visually similar enough that identification and counting of an intermixed patch can be onerous. Second, all species of Rubus produce a variable number of stems (ramets) in any given year, typically ranging between 2 and 5. Thus, even if a population is pure solely R. stipulatus, a simple count of the number of stems will not provide a consistent estimate of the number of individuals (genets) in the population. All population count data within the NHIS for R. stipulatus were assumed to be stem (ramet) counts. These counts were converted to population size (genets) ranges, estimated as one-fifth of the stem count up to one-half of the count recorded in NHIS.

Habitat Conditions: Suitable habitat is defined as areas of occupied and unoccupied habitat in which data or expert opinion suggest R. stipulatus individuals could successfully survive and reproduce for multiple generations. The size and quality of suitable habitat is taken into consideration in EO ranking. Generally, direct information on habitat size and quality is sparse in the NHIS for this species. Habitat condition was assessed for each EO using relevant surveyor notes if available in the NHIS.

Landscape Context: The connectedness of suitable habitat patches, the quality of the connecting buffer, and the security of the habitat are important landscape features for R. stipulatus. A high-quality protective buffer should create a contiguous area of native vegetation surrounding and connecting all suitable habitat patches in which deleterious human activity can be mitigated. To estimate the extent of buffering around each EO, a 250meter buffer around each EO was assessed for potential natural system modifications, such as hydrological impacts or fire suppression, and pressure from development and/or transportation corridors. Two metrics were used, the percent of impervious surface and the level of ditching or channelization within the buffer zone. Those metrics were combined into an aggregate score of “buffered”, “mostly buffered,” “likely impacted,” and “impacted.” Any relevant surveyor notes that were available in the NHIS were also considered.

Species-Specific Element Occurrence Ranks

All EOs for R. stipulatus were assigned EO ranks through an in-field or desktop analysis using standard guidelines. Hammerson et al.’s method uses standardized guidelines for ranking EOs, assuming the surveyor will incorporate species-specific attributes into their interpretation of those guidelines (e.g., life-history, habitat requirements). The definitions for EO quality ranks used for R. stipulatus in this assessment are:

A Quality: Defined as likely sustainable for a minimum of 20-30 years with compatible habitat management practices on-site and absence of off-site activities that are likely to influence the hydrology of site. The population is relatively invulnerable (does not decline or rebounds quickly) to stochastic events such as drought or flooding. The occurrence consists of multiple, discrete patches of the species that may function as a meta-population, with a minimum of 500 individuals total. In total, the occurrence patches occupy at least two acres of high-quality habitat within a much larger area of high-quality suitable habitat. There is a minimum of 200 feet of protective buffer around occupied habitat, and all suitable habitat patches within the wetland complex are connected. Non-native species may be present but minimal.  

B Quality: Defined as likely sustainable for a minimum of 20-30 years with compatible management habitat management practices on-site and off-site activities that could influence the hydrology of site are monitored and could be controlled. The population is likely invulnerable (does not decline or rebounds quickly) to stochastic events such as drought or flooding. Population consists of at minimum 250 individuals, occupies slightly less than two acres, or is found in medium quality habitat. Total area of suitable habitat is less than a typical A-Ranked occurrence. There is a minimum of 100 feet of protective buffer around occupied habitat, and most suitable habitat patches within a wetland complex are connected. Non-native species may be present but minimal. 

C Quality: Defined as unlikely to be extirpated in the near-term (within a generation), but persistence under current conditions is uncertain and population is vulnerable to decline due to stochastic events. Improvement in population viability is possible with compatible management and/or restorative conservation actions. Population size estimates do not warrant A or B ranking, but habitat occupied is of medium quality with some protective buffering around suitable habitat patches. Non-native species may be present at higher amounts but may not yet be dominant. 

D Quality: Defined as unlikely to be sustained for 10 years or one generation without immediate conservation actions. The population may already be functionally extirpated. Very small population size in poor quality habitat with little to no protective buffers. Non-native species dominate the community. 

E Quality: Viability not assessed, or data are too old or uncertain to be confident in another rank.  

X Quality: Extirpated

Protection and Management Metrics

Ownership: Land ownership for each EO was determined using publicly available land parcel resources and categorized as: private (individual or corporation) or by governmental unit (City, County, State or Federal) for publicly owned lands.

Protection: Land protection of an EO was assessed by considering land ownership and the designated use of the parcel from publicly available land records. The category of Protected was assigned to EOs on land that is permanently protected and designated for conservation or uses compatible with conservation (e.g., DNR-owned Scientific and Natural Areas, Wildlife Management Areas, National Forests). Informal Protection was assigned to EOs on land that does not have full protection, but is under easement or designated for uses that are likely to maintain its natural state, and it is unlikely to change ownership (e.g., County-owned Parks or Wilderness Areas). The No Protection category was assigned to EOs on land under private ownership, corporate ownership, or otherwise do not have any other assurances the natural area containing R. stipulaus will remain. 

Management: The likelihood of appropriate habitat management was assessed based on the availability of a formal management plan and expert knowledge of the sites containing EOs. Information on management was not found for many EOs. No management was assigned when the assessor was certain no management is currently taking place. Likely Yes or Likely No were assigned when the assessor was confident that management is or is not taking place, but not certain. The assessor had to be entirely certain active management is taking place on site for those EOs to be marked yes, they are managed. Those EOs were further categorized as having a management plan at either a site level, meaning the plan only addresses general habitat management needs, or a species-specific level, meaning the plan directly addressing enhancing or maintaining R. stipulatus.

Population Status Assessment for R. stipulatus

A population status assessment (by EO) for Rubus stipulatus in Minnesota was conducted with data as of Spring 2026. Download status assessment table.

Assessment Metrics

EO #	Current EO Rank	Population Size	Habitat Condition Notes	Landscape Context
32415	B	200+	Large contiguous habitat of approx. 850 acres	Buffered
36769	C	10 to 20	-	Buffered
36770	BC	20 to 100	-	Mostly Buffered
37035	CD	30-70+	Population occurs in multiple patches separated by development	Likely Impacted
39046	C	60-150	Contiguous habitat is small and heavily encroached by invasive shrubs; enacting management is difficult due to the small area and proximity to development on all sides	Likely Impacted
41422	E	Unknown	-	Buffered
41451	E	10+	-	Buffered
41734	B	260-650	Large contiguous habitat	Buffered
41735	B	300-750	Large contiguous habitat	Buffered
41736	CD	60-150	-	Likely Impacted
41821	E	Unknown	Most individuals within transportation right-of-way	Likely Impacted
41882	E	Unknown	-	Mostly Buffered
41883	C	<10	Population used to be multiple patches; most recent survey only found one small patch, despite an exhaustive search	Buffered
41887	BC	1,000-2,500	Population occurs in multiple patches separated by development	Likely Impacted
41919	X	0	-	N/A
41978	C	150-375	-	Mostly Buffered
41981	B	1,300-3,250	-	Mostly Buffered
41990	B	2,600-6,500	-	Mostly Buffered
42161	C	<10	-	Buffered
42176	CD	10 to 25	-	Impacted
42184	E	Unknown	-	Buffered
42560	CD	2 to 25	-	Mostly Buffered
42642	C	24 to 60	-	Mostly Buffered
42720	D	20 to 50	-	Impacted
42721	D	6 to 20	-	Buffered
42723	C	20 to 50	-	Mostly Buffered
42747	CD	4 to 10	-	Buffered
42754	D	26 to 81	Most individuals in transportation right-of-way	Mostly Buffered
42778	E	Unknown	-	Mostly Buffered
42804	E	Unknown	-	Buffered
42847	E	16-40	-	Likely Impacted
42853	C	30 to 75	Most individuals in transportation right-of-way	Mostly Buffered
42865	BC	500 to 1,875	Population occurs in multiple patches separated by development	Impacted
42957	D	<10	-	Likely Impacted
42958	D	6 to 15	-	Impacted
42959	E	Unknown	-	Likely Impacted
43002	CD	<10	-	Impacted
43030	E	6 to 15	Development planned in immediate vicinity of population.	Likely Impacted
43142	C	<10	-	Mostly Buffered
43192	C	20 to 110	-	Impacted
43194	CD	30-70+	-	Impacted

Trends

EO #	Current EO Rank	Last Survey	Trend
32415	B	2004	No Prior Survey
36769	C	2009	No Prior Survey
36770	BC	2009	No Prior Survey
37035	CD	2021	No Prior Rank
39046	C	2024	No Prior Rank
41422	E	2017	No Prior Survey
41451	E	2016	No Prior Survey
41734	B	2024	No Prior Rank
41735	B	2020	No Prior Survey
41736	CD	2013	No Prior Survey
41821	E	2020	No Prior Survey
41882	E	2021	No Prior Survey
41883	C	2025	No Prior Rank
41887	BC	2024	No Prior Rank
41919	X	2024	N/A
41978	C	2021	No Prior Survey
41981	B	2021	No Prior Survey
41990	B	2024	No Prior Rank
42161	C	2024	No Prior Rank
42176	CD	2024	No Prior Rank
42184	E	2021	No Prior Survey
42560	CD	2024	No Prior Survey
42642	C	2024	No Prior Survey
42720	D	2024	No Prior Survey
42721	D	2024	No Prior Survey
42723	C	2023	No Prior Survey
42747	CD	2024	No Prior Survey
42754	D	2024	No Prior Survey
42778	E	2020	No Prior Rank
42804	E	2024	No Prior Survey
42847	E	2022	No Prior Survey
42853	C	2022	No Prior Survey
42865	BC	2014	No Prior Survey
42957	D	2024	No Prior Survey
42958	D	2024	No Prior Survey
42959	E	2024	No Prior Survey
43002	CD	2024	No Prior Survey
43030	E	2025	No Prior Survey
43142	C	2025	No Prior Survey
43192	C	2025	No Prior Survey
43194	CD	2025	No Prior Survey

Site Information

EO #	Current EO Rank	Ecological Subsection	Land Ownership	Protection Status	Habitat Management
32415	B	Oak Savanna	County	Informal Protection	Unknown
36769	C	Anoka Sand Plain	Private	No Protection	No
36770	BC	Mille Lacs Uplands	Private	No Protection	No
37035	CD	Anoka Sand Plain	Mixed; Private & City	Informal Protection (Partial)	Likely Yes
39046	C	Anoka Sand Plain	State	Protected	Yes - Site Level
41422	E	Mille Lacs Uplands	County	No Protection	Likely No
41451	E	St. Louis Moraines	County	Informal Protection	Likely No
41734	B	Chippewa Plains	Federal	Protected	Unknown
41735	B	Chippewa Plains	Federal	Protected	Unknown
41736	CD	Anoka Sand Plain	Private	No Protection	Unknown
41821	E	Anoka Sand Plain	Private	No Protection	No
41882	E	Anoka Sand Plain	County	Informal Protection	Yes - Species Specific
41883	C	Anoka Sand Plain	Mixed; State & County	Protected	No
41887	BC	Anoka Sand Plain	Mixed; Private & County	No Protection	Yes - Species Specific
41919	X	Anoka Sand Plain	Private	N/A	N/A
41978	C	Anoka Sand Plain	Private	No Protection	Unknown
41981	B	Anoka Sand Plain	Private	No Protection	No
41990	B	St. Paul-Baldwin Plains	City	Informal Protection	Unknown
42161	C	Anoka Sand Plain	Private	Protected (Partial)	No
42176	CD	Anoka Sand Plain	Private	No Protection	No
42184	E	Mille Lacs Uplands	Private	No Protection	No
42560	CD	Anoka Sand Plain	County	Informal Protection	Unknown
42642	C	Mille Lacs Uplands	State	Protected	Unknown
42720	D	St. Paul-Baldwin Plains	Private	No Protection	No
42721	D	Anoka Sand Plain	County	Informal Protection	No
42723	C	Anoka Sand Plain	Private	No Protection	No
42747	CD	Anoka Sand Plain	Private	No Protection	No
42754	D	Chippewa Plains	Private	No Protection	No
42778	E	Anoka Sand Plain	City	No Protection	Unknown
42804	E	St. Louis Moraines	State	Informal Protection	No
42847	E	North Shore Highlands	Private	No Protection	No
42853	C	Pine Moraines & Outwash Plains	State	No Protection	No
42865	BC	Anoka Sand Plain	Mixed; Private & City	No Protection	No
42957	D	Anoka Sand Plain	State	Protected	Yes - Site Level
42958	D	Anoka Sand Plain	Private	No Protection	No
42959	E	Anoka Sand Plain	Mixed; Private & City	No Protection	No
43002	CD	Anoka Sand Plain	County	No Protection	No
43030	E	Anoka Sand Plain	Private	No Protection	No
43142	C	Anoka Sand Plain	State	Protected	Yes - Site Level
43192	C	Anoka Sand Plain	Private	No Protection	No
43194	CD	Anoka Sand Plain	Private	No Protection	No

Threat Assessment

A threat assessment for R. stipulatus was conducted based on the IUCN Threats Classification Scheme (IUCN, 2022). Threats in Minnesota were determined based on information from the MN DNRs Rubus stipulatus Rare Species Guide profile (MN DNR, 2026), the Rubus stipulatus NatureServe Explorer profile (NatureServe, 2024), and local expert opinion.

Download threat assessment as pdf

Development

Sub-Threats

Discussion

Housing and Urban Areas; Commercial and Industrial Areas

The core area of this species' range in MN is within the Anoka Sand Plain, an area experiencing explosive residential and commercial growth. As of 2026, there are 13 recorded residential or commercial development projects in Minnesota causing take of R. stipulatus. Unpermitted projects have likely also caused impacts. While direct mortality is a key stressor, there are also negative impacts through loss of surrounding habitat, habitat fragmentation, genetic isolation, and habitat degradation, particularly alteration in hydrology.

Corridors 

Sub-Threats

Discussion

Roads and Railroads; Utility and Service Lines

The construction and modification of roads associated with development is a source of past and likely future permitted takings. Also, there are several occurrences that have been reduced only to individuals remaining on degraded roadsides, right-of-way habitats, or utility corridors. R. stipulatus is not protected from taking in public road right of ways, so these occurrences are at particularly high risk.

System Modifications 

Sub-Threats	Discussion
Fire and Fire Suppression	The natural system that R. stipulatus is a part of is maintained by regular disturbance, such as fire. Altering the frequency of natural disturbances can have negative impacts. Active habitat management can be used to lessen negative impacts. The tools needed to accomplish this goal will vary from site to site, but dormant season prescribed burns are preferred. Burns must be conducted at a minimum four-year rotation (three growing seasons of rest between burns). R. stipulatus is top killed by fire and needs time to recover after disturbance.
Dams and water management or use	Groundwater resource use and changes to surface water hydrology in the Anoka Sand Plain have increased with development. Ditches, drain tiles, borrow pits, impoundments, storm water ponds, dewatering during the growing season and other ground and surface water abstraction are all deleterious to R. stipulatus’ habitat through changing ground or surface water dynamics. Even where populations occur on protected land, negative hydrologic impacts can occur if there is an insufficient buffer between the population and neighboring activities.

Problematic Species 

Sub-Threats

Discussion

Invasive Non-Native or Alien Species; Problematic Native Species

The small, fragmented nature of R. stipulatus’ habitat within a transition zone makes displacement by problematic species more likely due to edge effects. Phalaris arundinacea (Reed Canary Grass), exotic and aggressive native stands, and woody vegetation are the main concerns. If the extent of encroachment is limited, control methods should favor manual removal over use of chemical or heavy machinery, which carry additional risk to R. stipulatus.

Conservation Actions

Conservations actions recommended for R. stipulatus are based on the IUCN Conservation Actions Classification Scheme (IUCN, 2012a). The actions highlighted are those deemed the most critical to reaching the thresholds set in the recovery criteria. Priority conservation actions needed in Minnesota were determined based on information from the Rubus stipulatus Rare Species Guide profile (MN DNR, 2026), and local expert opinion.

Download conservation action assessment as pdf

Protection

Sub-Action	Discussion
Site or Area Protection	Land acquisition or easements should prioritize permanent protection of persistent populations with intact buffer habitat. Priority should be given to the high quality populations and populations in unique ecological conditions. Given the rapid development in the Anoka Sand Plain where most R. stipulatus populations occur, land protection for populations with an intact buffer is one of the most important conservation actions that can be taken to support this species recovery.
Resource and Habitat Protection	Land acquisition or easements should include areas surrounding known populations to create a protective buffer where negative impacts from hydrologic changes can be controlled and monitored.

Habitat Management

Sub-Action	Discussion
Site or Area Management	Develop and implement site level management plans that maintain or improve the quality of persistent populations. Dormant season prescribed burning with a minimum four-year rotation should be the favored mechanism for habitat management.
Invasive or Problematic Species Control	Reduce native and exotic shrub encroachment, ideally through prescribed burning or mechanical removal. Reduce Phalaris arundinacea encroachment, ideally through manual removal. Heavy machinery should be avoided to prevent soil damage. Chemical control should also be avoided, if possible, to prevent impacts to non-target species.
Habitat and natural process restoration	Restore unoccupied suitable habitat surrounding existing populations. Restore surrounding landscape matrix to create protective buffers with an emphasis on restoring natural hydrologic regimes.

Species Management

Sub-Action	Discussion
Species Re-Introductions	Augment known populations when it is necessary to ensure population viability. Re-introduce populations into protected, well managed areas. Habitat suitability and population size should be main factors in determining augmentation or re-introduction sites. Monitoring is necessary to evaluate these efforts and determine their success. Methods and goals should be adapted accordingly as new information is available. These efforts may also be used to re-connect populations within a fragmented landscape.
Genetic Preservation	Genetic preservation, for example through conservation seed-banking, should be conducted for at least one persistent population per Ecological Subsection. Additional emphasis should be given to populations in unique ecological conditions, deemed not viable, or those that will be subject to take. Salvage individual plants, including seed or vegetative material, that will be subject to take for preservation, re-introduction or augmentation into protected, well managed areas.

Law and Policy

Sub-Action	Discussion
Policies and regulations	Develop regulations to ensure projects are reviewed for the presence of the species in suitable habitat and potential impacts to the species. Develop regulations that ensure take, including harm, of all Rubus stipulatus is prohibited without a permit. Develop conservation guidelines for consistent protection of the species.
Private Sector Standards and Codes	Implement measures to ensure accurate species identification and high-quality survey results when done as part of natural heritage reviews.
Compliance and enforcement	Ensure development projects are reviewed for potential impacts to the species and protective measures and avoidance are implemented.

Capacity Building

Sub-Action	Discussion
Alliance and Partnership Building	Increased collaboration among responsible governmental units, conservation partners and private landowners to implement the recommendations in this plan for the protection and management of R. stipulatus populations and surrounding habitat.

Information Needs

Information need recommendations for R. stipulatus are based on the IUCN Research Needed Classification Scheme (IUCN, 2012b). The needs highlighted are those deemed the most critical to reaching the thresholds set in the recovery criteria. Priority information needs in Minnesota were determined based on information from the MN DNRs Rubus stipulatus Rare Species Guide profile (MN DNR, 2026) and local expert opinion.

Download information needs assessment as pdf

Research

Information Type	Discussion
Taxonomy	Create tools to improve in-field species identification and increase awareness of the importance of proper documentation or vouchering for species verification purposes. Even properly vouchered occurrences require a high level of expertise to identify in-field and verify from specimens.
Population Size	Most available data do not represent a comprehensive assessment of population size. More surveys are needed to fill in information gaps or update current viability assessments. Those surveys should document both the spatial extent of the population, census the number of individuals as stems and document reproductive output. Most available data are assumed to document stem (ramet) counts. Research is needed to improve the ability to estimate the effective population size (including overall number of genets) from a count of ramets. Research into methods for accurately estimating population size through the spatial extent of individuals instead of or in addition to stem counts would be beneficial.
Distribution	It is unlikely that R. stipulatus’ full statewide distribution has been documented. Continued surveys of potentially suitable habitat are needed and should be empirically informed by a species habitat model, as well as incorporate expert opinion.
Population genetics	It is known that past development in the core area of R. stipulatus’ statewide population has resulted in the fragmentation and destruction of populations. Population genetic research is needed to understand the impact of those activities on its current genetic diversity and gene flow. Population genetic research is needed to inform the movement of individuals in future augmentation and re-introduction efforts. Of particular importance will be information on historic patterns of gene flow, evidence of current inbreeding depression, and the potential risks or benefits of outbreeding.
Life History and Ecology	Most available data do not include an ecological assessment of the surrounding landscape. More comprehensive site information is needed to fill in information gaps or update current viability assessments. Those surveys should document the extent of currently unoccupied suitable habitat contiguous to currently occupied habitat, and the extent of the protective buffer connecting and surrounding those habitat patches. Research is needed to better understand R. stipulatus’ sexual and asexual reproductive success. Research is needed to determine R. stipulatus’ pollinator community. An assessment of habitat availability and suitability for the pollinator community should also be conducted where there is evidence of low reproductive success. Research is needed to determine whether R. stipulatus’ hybridizes with congeners.
Threats - Hydrology	Research is needed to understand the impacts of nearby groundwater resource extraction or alterations of surface hydrology on the viability of R. stipulatus.
Threats- Development	Development pressure often occurs in close proximity to R. stipulatus plants. Research is needed to better understand the buffer distance needed between a population and an activity to avoid negative impacts.
Conservation Actions - Augmentations and Re-Introductions	R. stipulatus populations impacted by development have been salvaged then translocated to a protected recipient site with appropriate habitat and management practices. Monitoring of augmentations, re-introductions and comparable control sites is needed to understand success and improve augmentation and re-introduction practices.
Conservation Actions - Propagation	Horticultural research is needed to inform best practices for propagating individuals through seed, cuttings or other methods, and proper care for out-planted individuals.

Conservation Planning 

Information Type	Discussion
Species Action or Recovery Plan	Re-evaluate R. stipulatus’ status and revise this recovery plan at least once every ten years. It is expected that as conservation actions are implemented and new information is available, recovery criteria will need to be modified accordingly. Track the implementation of actions recommended by this recovery plan to inform future revisions.

Monitoring

Information Type

Discussion

Population Trends

Better documentation of changes in size or extent in naturally occurring populations would help to inform R. stipulatus’ conservation status rank (s-rank) and could allow for adaptively managing populations. Base documentation should be at least one re-survey every five years, with more regular visits needed if monitoring is being used to support management decisions. All augmentations or re-introductions should be monitored annually for at least ten years to determine survival and reproductive success of transplanted individuals, and rates of recruitment and survival of first-generation offspring.

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References

Faber-Langendoen D, Nichols J, Master L, Snow K, Tomaino A, Bittman R, Hammerson G, Heidel B, Ramsay L, Teucher A, and Young B. 2012. NatureServe Conservation Status Assessments: Methodology for Assigning Ranks. NatureServe, Arlington, VA

IUCN. Conservation Actions Classification Scheme (Version 2.0). International Union for the Conservation of Nature 2012a. https://www.iucnredlist.org/resources/conservation-actions-classification-scheme

IUCN. 2012b. Research Needed Classification Scheme (Version 2.0). International Union for the Conservation of Nature. 2012b. https://www.iucnredlist.org/resources/research-needed-classification-scheme

IUCN. Threats Classification Scheme (Version 3.3). International Union for the Conservation of Nature. 2022. https://www.iucnredlist.org/resources/threat-classification-scheme

Master L, Faber-Langendoen D, Bittman R, Hammerson GA, Heidel B, Ramsay L, Snow K, Teucher A, and Tomaino A. 2012. NatureServe Conservation Status Assessments: Factors for Evaluating Species and Ecosystem Risk. NatureServe, Arlington, VA.

MN DNR. Rubus stipulatus. 2026. Minnesota Department of Natural Resources Rare Species Guide. https://www.dnr.state.mn.us/rsg/profile.html?action=elementDetail&selectedElement=PDROS1K7A0

NatureServe. Rubus stipulatus. 2024. https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.154280/Rubus_stipulatus

Acknowledgements

Authors:

Derek Anderson, Botanist | Minnesota Biological Survey

Holly Bernardo, Plant Survey Supervisor | Minnesota Biological Survey

Dustin Graham, Ecologist/Botanist | Minnesota Biological Survey

Bridget Henning-Randa, MN Endangered Species Consultant | Conservation and Management of Rare Resources Unit

Welby Smith, State Heritage Botanist | Minnesota Biological Survey

Contributors:

Lindsey Kemp – Project Administrator | Listed Species Program Coordinator | Conservation and Management of Rare Resources Unit

Linnea Lopez, Assistant Plant Ecologist | DNR Central Region

Amanda Wiese, Regional Plant Ecologist | DNR Central Region

Reviewers:

Megan Benage, Regional Ecologist | DNR Southwest Region

Nicholas Jensen, Regional Plant Ecologist | DNR Northwest Region

Mike Lee, Research Scientist | Minnesota Biological Survey

Becky Marty, Regional Plant Ecologist | DNR Northwest Region

Karen Updegraff, Regional Plant Ecologist | DNR Northeast Region

For More Information Contact:

Bridget Henning-Randa, MN Endangered Species Consultant

[email protected]