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Astragalus microcystis

Gray

Least Bladdery Milkvetch

G4Apparently Secure Found in 2 roadless areas NatureServe Explorer →
G4Apparently SecureGlobal Rank
LowThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.128259
Element CodePDFAB0F5A0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderFabales
FamilyFabaceae
GenusAstragalus
Other Common Names
Astragale utriculé (FR)
Concept Reference
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2023-08-21
Change Date2023-08-18
Edition Date2023-08-18
Edition AuthorsNordman, C. (2023).
Threat ImpactLow
Range Extent20,000-200,000 square km (about 8000-80,000 square miles)
Number of Occurrences21 - 80
Rank Reasons
Astragalus microcystis occurs in western North America, in the northwestern United States, and southern Canada. It occurs in western Montana, Washington, southern British Columbia, and historically in Idaho. There are about 40 occurrences documented between 1982 and 2023, and the total population size of Astragalus microcystis is not known, but is likely more than 10,000 plants. Threat impacts may be low, probably including impacts to streambank, riverbank, and gravel bar habitats from dams and water management.
Range Extent Comments
Astragalus microcystis occurs in western North America, in the northwestern United States, and southern Canada. It occurs in western Montana, Washington, southern British Columbia, and historically in Idaho. It is not documented in Wyoming. The range extent was estimated to be about 182,000 square kilometers, using herbarium specimens, photo-based observations, and NatureServe Network occurrence data collected between 1982 and 2023 (GBIF 2023, iNaturalist 2023, NatureServe 2023, Nelson and Legler 2023, SEINet 2023).
Occurrences Comments
By applying a 1 km separation distance to herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1982 and 2023, it is estimated that there are about 40, or between 21 and 80 occurrences of Astragalus microcystis rangewide (GBIF 2023, iNaturalist 2023, NatureServe 2023, SEINet 2023).
Threat Impact Comments
Threats are not well documented, but may be of low impact overall, and probably include impacts to streambank, riverbank, and gravel bar habitats from dams and water management. Erosion associated with introduced mountain goat impacts has been a threat in the Olympic Mountains (WA NHP 2013).
Ecology & Habitat

Habitat

This species is found in alpine and subalpine areas in fellfields, and cushion plant communities of the Olympic Mountains, and mountains in Montana, on limestone and dry, gravelly soils and sandy areas, and in eastern Washington and Montana on riverbanks, streambanks, grasslands, and in open woods, in gravelly to sandy areas, occurs at 350 - 2500 meters (1150 - 8200 feet) elevation (Lesica 2012, MNHP 2023, SEINet 2023, WA NHP 2013).
Terrestrial Habitats
Forest/WoodlandAlpine
Palustrine Habitats
Riparian
Other Nations (2)
CanadaN2
ProvinceRankNative
British ColumbiaS2Yes
United StatesN4
ProvinceRankNative
IdahoSHYes
MontanaS4Yes
WashingtonS2Yes
WyomingSNRYes
Threat Assessments
ThreatScopeSeverityTiming
7 - Natural system modificationsSmall (1-10%)Serious or 31-70% pop. declineHigh (continuing)
7.2 - Dams & water management/useSmall (1-10%)Serious or 31-70% pop. declineHigh (continuing)

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Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)Yes
Roadless Areas (2)
Montana (1)
AreaForestAcres
Lolo CreekLolo National Forest14,335
Washington (1)
AreaForestAcres
QuilceneOlympic National Forest18,656
References (9)
  1. Global Biodiversity Information Facility (GBIF). 2023. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2023).
  2. iNaturalist. 2023. Online. Available: https://www.inaturalist.org (accessed 2023).
  3. Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
  4. Lesica, P. 2012a. Manual of Montana Vascular Plants. Botanical Research Institute of Texas, Fort Worth, TX. 771p.
  5. Montana Natural Heritage Program (MNHP). 2023. Least Bladdery Milkvetch — <i>Astragalus microcystis</i>. Montana Field Guide. Montana Natural Heritage Program. Online. Available: https://FieldGuide.mt.gov/speciesDetail.aspx?elcode=PDFAB0F5A0 (accessed 2023).
  6. NatureServe. 2023. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  7. Nelson, B.E. and B.S. Legler. 2023. Checklist of the Wyoming Flora. Rocky Mountain Herbarium, University of Wyoming, Laramie, WY. Online. Available: https://www.rockymountainherbarium.org/index.php/research/checklist (Accessed 2023).
  8. Southwest Environmental Information Network (SEINet). 2023. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2023).
  9. Washington Natural Heritage Program. 2013. Description of <i>Astragalus microcystis</i> in Washington. Online. Available: https://www.dnr.wa.gov/publications/amp_nh_asmi4.pdf (Accessed 2023).