Plants, land and wetlands indicators – Vascular plants

Reporting on the general status of vascular plants in Alberta.

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  • Plants, land and wetlands indicators – Vascular plants

About the indicator

Plants are an important component of Alberta’s biological diversity (biodiversity) and provide information about the state of our natural ecosystems.

Plants provide oxygen, food, medicine, clothing and wildlife habitat, among other values. Plants also help regulate the climate by sequestering carbon and can improve air, water and soil quality by acting as a filter.

This indicator summarizes the general status of vascular plants in Alberta in 2015 and 2020, as reported by the Canadian Endangered Species Conservation Council (2016, 2022). This indicator also reports on the status of non-native or exotic vascular plant species in the province.

Vascular plants facts

  • Vascular plants make up the majority of all terrestrial plants and include any plant with specialized vascular tissue (xylem and phloem) to transport water and nutrients. These include ferns, clubmosses, horsetails, conifers and flowering plants, all of which are represented in the Alberta flora.
  • The estimated global flora of vascular plants is over 350,000 species (Antonelli et al. 2023) with 5,300 in Canada (Canadian Endangered Species Conservation Council 2020) and approximately 2,000 reported for Alberta (Alberta Conservation Information Management System 2022).
  • Many vascular plant species have a wide geographic distribution throughout North America but occur at the edge of their range in Alberta.
  • Major threats to vascular plants nationally include habitat loss and alteration, disturbance, invasive species and climate change (McCune et al. 2013, McCune and Morrison 2020, Rosenthal et al. 2020).
  • Given incomplete information on population trends, abundance and distribution for Alberta's plant species, this indicator uses the widely reported metric of species conservation status to reflect the overall status of vascular plants in Alberta.

Data collection and analysis

  • General status of vascular plants in Alberta

    The federal government, in consultation with provincial and territorial jurisdictions, compiles data on the status of species, including vascular plants, every 5 years. This process is referred to as General Status and results in a series of reports known as Wild Species: The General Status of Species in Canada (Canadian Endangered Species Conservation Council). Vascular plant information from conservation data centres across Canada is provided as part of this process.

    A record of all known plants for the province is included in the Alberta Conservation Information Management System (ACIMS). It is the primary source of vascular plant data for Alberta and is updated regularly from a variety of sources. ACIMS is part of the NatureServe network of conservation data centres and provides Alberta plant data to the General Status initiative.

    The next General Status evaluation for vascular plants will take place in 2025.

    Conservation status ranks

    Members of the NatureServe network (including ACIMS) and the General Status process use standardized ranks to assign a conservation status to a species (see Table 1). These ranks are used for reporting this indicator.

    • Data from within the network and other sources are used to assess conservation status (potential risk of extinction) at the subnational, national and global scales (Faber-Langendoen et al. 2012, Master et al. 2012).
    • A species (or taxon) will have 3 ranks in Alberta: global (G rank from NatureServe), national (N rank from General Status) and subnational (S rank from ACIMS).
    • At each level (global, national or subnational), a species (or taxon) is ranked from 1 (critically imperiled) to 5 (secure; Table 1).
    • The use of the combination of global, national and subnational ranks provides a synopsis of each rank in relation to the other. When the G rank for a species is higher than the N or S rank, this indicates that it is found in other jurisdictions and is likely either more common there or occurs in a number of other places. An S rank with a similar G or N rank suggests that the jurisdiction has a significant portion of the population.
    • For example, Aquilegia jonesii occurs outside of Alberta and thus has a G rank of G3. This species is ranked S3 in Montana and S2 in Wyoming (NatureServe Explorer, 2024). Alberta is the only Canadian jurisdiction where the species is known, and it is rare in the province which is reflected in the N rank of N1 and S rank of S1.

    How the status assessment process works

    The General Status process results in the identification of plants that may be at risk in Canada.
    The national Committee on the Status of Endangered Wildlife in Canada (COSEWIC) may commission detailed status reports for those species that have been identified through the General Status process as high priority. Priorities are determined based on level of risk and percentage of the world range in Canada (Canadian Endangered Species Conservation Council, 2022).

    COSEWIC assesses the status of a species (Endangered, Threatened, Special Concern, Data Deficient, Not at Risk) based on a detailed status report. It subsequently makes a recommendation on listing to the federal Minister of Environment and Climate Change Canada who then may recommend listing under the federal Species at Risk Act.

    Provincially, a detailed status report may be commissioned by the Government of Alberta. The Scientific Subcommittee (SSC) of the Endangered Species Conservation Committee (ESCC):

    • uses the detailed status report and International Union for Conservation of Nature (IUCN) criteria to assess population trends, size and distribution of the species
    • provides recommendations to the ESCC on the most appropriate detailed status designation (endangered, threatened, special concern or data deficient).

    The ESCC in turn provides a recommendation to the Minister of Environment and Protected Areas regarding listing under the Alberta Wildlife Act.

    Only plants that are listed under the provincial Wildlife Act or Schedule 1 of the federal Species at Risk Act have legal protection. Status or ranks of General Status, COSEWIC, and ACIMS confer no legal protection for any species.

  • Methods

    This indicator is based on changes to the General Status of plants found in Alberta. The indicator was selected because:

    • status is assessed every 5 years which is a consistent period of time in which to compare results
    • ranks are reviewed by a team of experts as part of this process
    • standardized methodology is used consistently across Canada to assess status

    Vascular plant data for Alberta from the General Status 2015 and 2020 reports (Wild Species: The General Status of Species in Canada) were compiled and these datasets were compared to assess changes to the flora (taxonomic changes, additions or deletions) and changes to status.

    This indicator focuses on the number of species in the various rank categories rather than on individual taxa.

    Changes to the assessment process after 2010

    Slight changes in the assessment process used by NatureServe programs after the 2010 General Status exercise means that we are unable to accurately compare the results of the 2005 and 2010 assessments to those from 2015 and 2020.

    While there is a General Status report for 2000, it includes only a subset of vascular plants (ferns and orchids) and is therefore not included in this reporting.

    Taxonomy

    Taxonomy, a branch of science that explores the relationship of species to each other, is dynamic and often results in changes to our concepts of individual species. As a result:

    • individuals of what we thought were 2 or more different species may be lumped together into one
    • one species may split into 2 or more new taxonomic groups (taxa)

    Species lists for an area therefore may change due to new discoveries, extirpations or changes to taxonomy. Changes to taxonomy and errors in reporting were taken into account when presenting the results for this indicator.

    Naming conventions

    This indicator reports vascular plant species by their scientific names and includes common names when available.

    • Scientific names are standardized, unique Latin or Latinized names assigned to each species, and used by scientists and others across the world to precisely identify species and communicate about them. Scientific names typically comprise 2 words, which include the genus and species name, respectively.
    • Common names often differ across different regions and are changed more easily and often compared to scientific names. More than one common name is often used for the same plant species, and specific common names sometimes refer to many different species.

    The Database of Vascular Plants of Canada (VASCAN) is the primary source for scientific and common names for General Status and conservation data centres (including ACIMS) and is the source used here as well. VASCAN is attempting to standardize common names, both English and French, for plants in Canada.

  • Data limitations

    This indicator provides a snapshot in time of the General Status of vascular plant species reported to occur in Alberta at the time of the latest assessment in 2020.

    • The number of vascular species reported in datasets like ACIMS, General Status and VASCAN will change over time due to new discoveries, changes in nomenclature or taxonomy or additional information on the origin of taxa. Initiatives such as the Flora of North America, provincial floras and species experts are used to update such datasets.
    • The number of species reported on in the General Status reports and ACIMS differs because General Status does not report on hybrids, varieties and subspecies, which are included in ACIMS.

    General Status ranks and reports are based on the best available data provided by jurisdictions. The data are highly variable between species. A species for which there is a detailed status report will have much more information than will others that have not had as much attention and resources. The information used in all processes can include published studies, observations, opinions of experts and population modeling, among others.

    General Status reports are based on information provided by ACIMS and other members of the NatureServe network. The reports are published every 5 years and are not updated between assessments. New data and information will be included in the next status report, and this indicator will be updated when the new status report is available.

Table 1. Ranks and conservation status of vascular plant species and ecological communities used by NatureServe and General Status. These ranks are applied at both a Subnational (S rank), National (N rank) and Global (G rank) scale.

Rank (S/N/G)Conservation status category
1Critically imperiled
At very high risk of extirpation in the jurisdiction due to very restricted range, very few populations or occurrences, very steep declines, severe threats, or other factors.
2Imperiled
At high risk of extirpation in the jurisdiction due to restricted range, few populations or occurrences, steep declines, severe threats, or other factors.
3Vulnerable
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.
4Apparently secure
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.
5Secure
At very low or no risk of extirpation in the jurisdiction due to a very extensive range, abundant populations or occurrences, with little to no concern from declines or threats.
HPossibly extirpated
Known from only historical records but still some hope of rediscovery. There is evidence that the species or ecosystem may no longer be present in the jurisdiction, but not enough to state this with certainty.
XPresumed extirpated
Species is believed to be extirpated from the jurisdiction. Not located despite intensive searches of historical sites and other appropriate habitat, and virtually no likelihood that it will be rediscovered.
N/ANot applicable
The rank is not applicable because the species is not a suitable target for conservation activities (example: exotic and accidental species).
NRNot ranked
Conservation status not yet assessed.
UUnknown
Currently unrankable due to lack of information or due to substantially conflicting information about status or trends.

Summary of key results

Last updated: September 2024

  • In 2020, 1,615 native vascular plant species were included in the General Status report for Alberta (Figures 1 and 2). See Wild Species: The General Status of Species in Canada for the full report.
    • 704 vascular plants (44%) were ranked S5 or S4(secure or apparently secure).
    • 499 plant species (31%) were ranked S3 (vulnerable).
    • 176 species (11%) were ranked S2 and 168 species (10%) were ranked S1, meaning that they may be at risk. General status ranks S1 and S2 include plants that are naturally rare and not currently at risk to habitat loss or alteration but may be under threat from climate change and stochastic (unpredictable) events.
    • 10 vascular plant species (<1%) have not been seen recently and have been ranked SH (possibly extirpated) in Alberta.
    • Two vascular plant species (<1%) have not been adequately assessed (SNR) and the status of 56 species (3%) is unknown (SU), often due to issues with taxonomy.
  • Three species were discovered or newly reported between 2015 and 2020 and these are: Yoho paintbrush (Castilleja purpurascens) (S1), Fraser's St. John's-wort (Hypericum fraseri) (SU) and compact flax (Linum compactum) (SU). The rank of SU was applied to Fraser’s St. John’s-wort and compact flax pending more information.
  • Three newly described species are found in Alberta including Michigan moonwort (Botrychium michiganense), North American moonwort (Botrychium neolunaria) and Hudson's cinquefoil (Potentilla hudsonii). These are not new discoveries but rather the result of changes in taxonomy and revisions to the concepts of closely related species.
  • Ribbon-leaved pondweed (Potamogeton epihydrus) was reported by the Alberta Biodiversity Monitoring Institute and is reported in General Status 2020. However, the status of this species is unknown and thus remains as a potential addition pending more information.
  • Several plant species included in the General Status for Alberta are naturally rare or uncommon plants while some are rare due to human activities. Several plants, some of which are rare or uncommon, have their entire Canadian population within Alberta. For more information, see the fact sheet:

Figure 1. Alberta’s native vascular plant species and their NatureServe status ranks in 2015 and 2020

Chart data table
Year S1 S2 S3 S4 S5 SH SNR SU
2015 165 178 505 287 421 11 36
2020 168 176 499 286 418 10 2 56

Source: Government of Alberta

Accessible chart description

Stacked bar graph showing the number of native vascular plant species in Alberta grouped by NatureServe status ranks in 2015 and 2020. In 2020, 704 vascular plants (44%) were ranked S5 or S4 (secure or apparently secure), 499 plant species (31%) were ranked S3 (vulnerable), 176 species (11%) were ranked S2 and 168 species (10%) were ranked S1, meaning that they may be at risk. Ten vascular plant species (<1%) have not been seen recently and have been ranked SH (possibly extirpated) in Alberta. Two vascular plant species (<1%) have not been adequately assessed (SNR) and the status of 56 species (3%) is unknown (SU), often due to issues with taxonomy.

Figure 2. Proportion of NatureServe status ranks for Alberta’s native vascular plant species in 2020

Chart data table
General status rank Native vascular plant species
S1, 10‌% 168
S2, 11‌% 176
S3, 31‌% 499
S4, 18‌% 286
S5, 26‌% 418
SH, 1‌% 10
SNR, 0‌% 2
SU, 3‌% 56

Source: Government of Alberta

Accessible chart description

Pie chart showing the proportion of general status ranks for Alberta’s native vascular plant species in 2020. Total number of plant species and their respective percentage is provided for each NatureServe status rank. In 2020, 704 vascular plants (44%) were ranked S5 or S4 (secure or apparently secure), 499 plant species (31%) were ranked S3 (vulnerable), 176 species (11%) were ranked S2 and 168 species (10%) were ranked S1, meaning that they may be at risk. Ten vascular plant species (<1%) have not been seen recently and have been ranked SH (possibly extirpated) in Alberta. Two vascular plant species (<1%) have not been adequately assessed (SNR) and the status of 56 species (3%) is unknown (SU), often due to issues with taxonomy.

Vascular plant species by plant habit

  • Plants are often described by their general appearance, or plant habit, including their size and growth form. We used a modified version of the plant habits provided by VASCAN to categorize plants into 6 habits: trees, shrubs, vines, forbs, grasses and grass-like, and ferns and allies.
  • Of the 1,615 native vascular plants included in the General Status 2020 for Alberta, 37 (2%) are trees, 136 (8%) are shrubs, 3 (<1%) plants are vines, 1,007 (62%) species are forbs, 354 (22%) are grasses and grass-like species and 78 (5%) are ferns and allies (Figure 3).
  • 53 (3%) species are aquatic vascular plants, all of which are forbs, that grow in or near water. One third of these aquatic plants are ranked S1 and S2 (not shown).

Figure 3. Plant habit of Alberta’s native vascular plant species in 2020

Chart data table
Tree Shrub Vine Forb Grasses and grass-like Ferns and allies
Number of species 37 136 3 1007 354 78
Source: Government of Alberta
Accessible chart description

Stacked bar graph showing the plant habit of Alberta’s native vascular plant species in 2020. Of the 1,615 native vascular plants, 37 (2%) are trees, 136 (8%) are shrubs, 3 (<1%) plants are vines, 1,007 (62%) species are forbs, 354 (22%) are grasses and grass-like species and 78 (5%) are ferns and allies.

Detailed status designations

As of April 2024, 9 vascular plant species have completed detailed status assessments of which 7 have been assigned legal designations under Alberta’s Wildlife Act:

  • Six vascular plants species have been designated Endangered:
    • Limber pine (Pinus flexilis)
    • Slender mouse-ear-cress (Cruchihimalaya virgata)
    • Soapweed (Yucca glauca)
    • Tiny cryptantha (Cryptantha minima)
    • Western spiderwort (Tradescantia occidentalis)
    • Whitebark pine (Pinus albicaulis)
  • One species, small-flowered sand-verbena (Trypterocalyx micranthus), is designated Threatened, meaning that it will likely become endangered if limiting factors such as dune stabilization, habitat loss and competition from invasive species are not reversed (Alberta small-flowered sand-verbena Recovery Team, 2012; Alberta Sustainable Resource Development 2003).
  • Two species are designated Special Concern as they are particularly sensitive to human activities or natural events:
    • Hare’s-foot locoweed (also called hare-footed locoweed) (Oxytropis lagopus)
    • Western blue iris (also called western blue flag) (Iris missouriensis)
  • An additional 4 species found in Alberta are listed under Schedule 1 of the federal Species at Risk Act:
    • Bolander’s quillwort (Isoetes bolanderi)
    • Smooth goosefoot (Chenopodium subglabrum)
    • Dwarf woollyheads (Psilocarphus brevissimus) (prairie population)
    • Floccose tansy (Tanacetum huronense floccosum)

Non-native species

  • Non-native plants, often referred to as exotic or alien, are species that have been introduced to Alberta accidentally or deliberately.
  • A species may be native to one area but exotic in another. Ponderosa pine (Pinus ponderosa) for example, is a common naturally occurring tree in the interior of British Columbia but introduced in Alberta and thus considered to be exotic here.
  • Alberta regulates plant species that present significant economic, social or ecological risks under the Weed Control Act and the accompanying Weed Control Regulation. The regulation includes a schedule of 46 plants that are prohibited noxious weeds (Schedule 1) and 29 plants that are declared noxious weeds (Schedule 2). Not all species included on these schedules are currently known from the province but have a high likelihood of occurring in the future.
    • Due to their rapid spread and high competitiveness, noxious weeds must be controlled, and prohibited noxious weeds must be destroyed (the latter are either not currently found in Alberta or are limited to few locations making eradication possible).
  • Sixteen aquatic invasive plant species are identified as prohibited throughout Alberta under Item 2 of the Schedule in the Fisheries (Alberta) Act. These species are illegal to be imported, sold, transported or possessed in Alberta. For more information, see the Don’t let it loose resources.
  • Among Alberta’s 1,965 vascular plant species ranked as part of the 2020 General Status process (Endangered Species Conservation Council 2022), 1,615 species (82%) were native and 350 species (18%) were exotic (Figure 4). Twelve new exotic species were reported for Alberta between 2015 and 2020.
  • Of the 350 exotic plant species identified as occurring in Alberta, 49 species (14%) are considered invasive and are provincially regulated under Alberta’s Weed Control Act, including 29 noxious weeds and 20 prohibited noxious weeds (Figure 4).

Figure 4. Alberta’s native and non-native vascular plants in 2020

Chart data table
Category Native vascular plant species
Native, 82‌% 1615
Noxious, 2‌% 29
Prohibited Noxious, 1‌% 20
Non-regulated, 15‌% 301

Source: Government of Alberta

Accessible chart description

Pie chart showing the proportion of native and non-native vascular plant species in Alberta in 2020. Non-native plants include species designated as Noxious and Prohibited Noxious under Alberta’s Weed Control Act as well as non-regulated exotics. Total number of plant species and their respective percentage is provided for each category. Among Alberta’s 1,965 vascular plant species ranked as part of the 2020 General Status process, 1,615 species (82%) were native and 350 species (18%) were exotic. Of the 350 exotic plant species identified as occurring in Alberta, 49 species (14%) are considered invasive, including 29 noxious weeds and 20 prohibited noxious weeds.

References

  • Alberta Conservation Information Management System (ACIMS) 2022.
  • Alberta Small-flowered Sand-verbena Recovery Team. 2012. Alberta Small-flowered Sand-verbena Recovery Plan 2012-2017. Alberta Environment and Sustainable Resource Development, Alberta Species at Risk Recovery Plan No. 24. Edmonton, AB. 27 pp.
  • Alberta Sustainable Resource Development. 2003. Status of the Small-flowered Sand Verbena (Tripterocalyx micranthus) in Alberta. Alberta Sustainable Resource Development, Fish and Wildlife Division, and Alberta Conservation Association, Wildlife Status Report No. 48, Edmonton, AB. 24 pp.
  • Antonelli, A. et al. 2023. State of the World’s Plants and Fungi 2023. Tackling the Nature Emergency: Evidence, gaps and priorities. Royal Botanic Gardens, Kew.
  • Canadian Endangered Species Conservation Council. 2022. Wild Species 2020: The General Status of Species in Canada. National General Status Working Group: 172 pp.
  • Faber-Langendoen, D., J. Nichols, L. Master, K. Snow, A. Tomaino, R. Bittman, G. Hammerson, B. Heidel, L. Ramsay, A. Teucher, and B. Young. 2012. NatureServe Conservation Status Assessments: Methodology for Assigning Ranks. NatureServe, Arlington, VA.
  • Master, L. L., D. Faber-Langendoen, R. Bittman, G. A. Hammerson, B. Heidel, L. Ramsay, K. Snow, A. Teucher, and A. Tomaino. 2012. NatureServe Conservation Status Assessments: Factors for Evaluating Species and Ecosystem Risk. NatureServe, Arlington, VA.
  • McCune, J. L., W. L. Harrower, S. Avery-Gomm, J. M. Brogan, A.-M. Csergő, L. N. K. Davidson, A. Garani, L. R. Halpin, L. P. J. Lipsen, C. Lee, J. C. Nelson, L. R. Prugh, C. M. Stinson, C. K. Whitney, and J. Whitton. 2013. Threats to Canadian species at risk: an analysis of finalized recovery strategies. Biological Conservation 166 (2013) 254–265.
  • McCune, J. L. and P. D. S. Morrison. 2020. Conserving plant species at risk in Canada: land tenure, threats, and representation in federal programs. FACETS 5: 538–550. doi:10.1139/facets-2019-0014
  • Rosenthal, J. R. Booth, N. Carolan, O. Clarke, J. Curnew, C. Hammond, J. Jenkins, E. McGee, B. Moody, J. Roman, K. Rossi, K. Schaefer, M. Stanley, E. Ward, and L. Weber. 2022. The impact of recreational activities on species at risk in Canada. Journal of Outdoor Recreation and Tourism 40 (2022) 100567

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