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Astragalus robbinsii

(Oakes) Gray

Robbins' Milkvetch

G5Secure Found in 14 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
PSESA Status
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.147777
Element CodePDFAB0F7P0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderFabales
FamilyFabaceae
GenusAstragalus
USESAPS
COSEWICPS:SC
Other Common Names
Astragale de Robbins (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 Date2025-01-24
Change Date1988-02-24
Edition Date2025-01-24
Edition AuthorsELIZABETH H. THOMPSON, EHTF, rev. N. Ventrella (2025)
Threat ImpactUnknown
Range Extent>2,500,000 square km (greater than 1,000,000 square miles)
Number of Occurrences81 - 300
Rank Reasons
Astragalus robbinsii is a perennial forb occurring in a variety of habitat types, including riparian, rock outcrops, ledges, gravel bars, meadows, thickets, moraines, tundra, and coastal bluffs of North America. It has two centers of distribution in the United States and Canada, from New Mexico to Alaska, and New England north to eastern Canada. There are estimated to be over 200 occurrences rangewide, which are threatened by development, rights-of-way maintenance, alteration of hydrology, erosion, succession, recreational activities, invasive species, climate change, and other threats in some places. Little is known about threats and trends, but with a large range extent, high number of occurrences, abundant habitat, broad habitat preferences, and no obvious intrinsic vulnerabilities, Astragalus robbinsii is considered secure.
Range Extent Comments
Astragalus robbinsii occurs in North America, where it has two centers of distribution: from New Mexico to Alaska and New England north to eastern Canada (FNA 2023). Range extent was estimated using herbarium specimens and photo-based observations collected between 1994 and 2025 (GBIF 2025, iNaturalist 2025, SEINet 2025). See individual entries for distribution details about the eight varieties.
Occurrences Comments
By applying a 1 km separation distance to herbarium records and photo-based observations documented between 1994 and 2025, there are estimated to be over 200 occurrences rangewide (GBIF 2025, iNaturalist 2025, SEINet 2025).
Threat Impact Comments
Although threats are not widely documented, Astragalus robbinsii is threatened by development, rights-of-way maintenance, alteration of hydrology, erosion, succession, recreational activities, invasive species, climate change, and other threats in some places (NatureServe 2025).
Ecology & Habitat

Habitat

Astragalus robbinsii occurs in a variety of habitat types, including brushy stream banks, river banks, moist soils of timbered creek beds, schist rock outcrops along river banks, granite, limestone ledges near and above water, gravel bars, banks in alder, spruce, and birch woods, meadows, thickets, moraines in humus or alluvial soils, alpine tundra, and limestone or calcareous sandstone terraces and bluffs near the coast (FNA 2023).
Terrestrial Habitats
Forest/WoodlandWoodland - MixedGrassland/herbaceousTundraBare rock/talus/screeCliff
Palustrine Habitats
FORESTED WETLANDRiparian
Other Nations (2)
United StatesN5
ProvinceRankNative
New MexicoSNRYes
NevadaS4Yes
OregonSNRYes
ColoradoS3Yes
WashingtonSNRYes
UtahS1Yes
New HampshireSNRYes
AlaskaS3Yes
MaineS1Yes
VermontS2Yes
MontanaS4Yes
WyomingS2Yes
IdahoSNRYes
CanadaN5
ProvinceRankNative
British ColumbiaS5Yes
Yukon TerritorySUYes
AlbertaS3Yes
QuebecSNRYes
Island of NewfoundlandS1Yes
LabradorS1Yes
Nova ScotiaS1Yes
Threat Assessments
ThreatScopeSeverityTiming
1 - Residential & commercial developmentUnknownUnknownUnknown
4 - Transportation & service corridorsUnknownUnknownUnknown
4.2 - Utility & service linesUnknownUnknownUnknown
6 - Human intrusions & disturbanceUnknownUnknownUnknown
6.1 - Recreational activitiesUnknownUnknownUnknown
7 - Natural system modificationsUnknownUnknownUnknown
7.1 - Fire & fire suppressionUnknownUnknownUnknown
7.1.2 - Suppression in fire frequency/intensityUnknownUnknownUnknown
7.2 - Dams & water management/useUnknownUnknownUnknown
8 - Invasive & other problematic species, genes & diseasesUnknownUnknownUnknown
8.1 - Invasive non-native/alien species/diseasesUnknownUnknownUnknown
8.1.1 - Unspecified speciesUnknownUnknownUnknown
9 - PollutionUnknownUnknownUnknown
9.3 - Agricultural & forestry effluentsUnknownUnknownUnknown
9.3.2 - Soil erosion, sedimentationUnknownUnknownUnknown
11 - Climate change & severe weatherUnknownUnknownUnknown

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Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)Yes
Roadless Areas (14)
Alaska (2)
AreaForestAcres
Chilkat-West Lynn CanalTongass National Forest199,772
College FiordChugach National Forest1,130,818
Idaho (2)
AreaForestAcres
Boulder - White CloudsSalmon-Challis National Forest139,297
Boulder - White CloudsSawtooth National Forest322,653
Maine (1)
AreaForestAcres
Caribou - Speckled ExtWhite Mountain National Forest5,988
Montana (1)
AreaForestAcres
Zulu #166Kootenai National Forest10,010
Nevada (2)
AreaForestAcres
Ruby - Lamoille CynHumboldt-Toiyabe National Forest32,771
Ruby - ThompsonHumboldt-Toiyabe National Forest5,289
New Mexico (1)
AreaForestAcres
PecosCarson National Forest13,436
Oregon (2)
AreaForestAcres
Hurricane CreekWallowa-Whitman National Forest1,606
Little SheepWallowa-Whitman National Forest5,238
Washington (3)
AreaForestAcres
Long SwampOkanogan National Forest66,344
Mt. BonaparteOkanogan National Forest10,891
TiffanyOkanogan National Forest22,045
References (6)
  1. Flora of North America Editorial Committee (FNA). 2023. Flora of North America north of Mexico. Vol. 11. Magnoliophyta: Fabaceae, parts 1+2. Oxford Univ. Press, New York. xxvii + 1108 pp.
  2. Global Biodiversity Information Facility (GBIF). 2025. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2025).
  3. iNaturalist. 2025. Online. Available: https://www.inaturalist.org (accessed 2025).
  4. 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.
  5. Knapp, W.M., A. Frances, A., R. Noss, R.F.C. Naczi, A. Weakley, G.D. Gann, B.G. Baldwin, J. Miller, P. McIntyre, B.D. Mishler, B.D., G. Moore, R.G. Olmstead, A. Strong , K. Kennedy, K., B. Heidel, and D. Gluesenkamp. 2021. Vascular plant extinction in the continental United States and Canada. Conservation Biology. <a href="https://doi.org/10.1111/cobi.13621">https://doi.org/10.1111/cobi.13621</a>
  6. Southwest Environmental Information Network (SEINet). 2025. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2025).