E-Flora BC: Electronic Atlas of the Flora of British Columbia

Astragalus alpinus L.
Alpine Milk-vetch (Alaskan Sagebrush; alpine milkvetch)
Fabaceae (Pea family)

Introduction to Vascular Plants

© Virginia Skilton  Email the photographer   (Photo ID #2755)

E-Flora BC Static Map
Distribution of Astragalus alpinus
Click here to view our interactive map and legend
Details about map content are available here
Click on the map dots to view record details.

Astragalus alpinus var. alpinus

Species Information

Click on the image below to view an expanded illustration for this species.

Low mat-forming perennial herb from a taproot and rhizomes; stems few to several, decumbent to ascending, 5-35 cm long, slender, branched, with short, appressed, unbranched hairs.
Alternate, pinnately compound, 5-15 cm long, stalked; leaflets 13 to 25, egg-shaped to oblong-elliptic, rounded to notched at the tip, 5-15 (20) mm long, appressed-hairy, the stalks equal to or longer than the leaves; stipules 1-8 mm long, the lower ones joined and clasping the stem.
Inflorescence a short, axillary raceme of 5 to 30 pea-like flowers, the flowers ascending at first, later nodding, the racemes 1-6 cm long on stalks from shorter to longer than the leaves; corollas pinkish- to bluish-purple, often white towards the base, 7-15 mm long, the darker-purple keel about as long as the banner, both longer than the wings; calyces bell-shaped, short-black-hairy, 3-6 mm long, the awl-shaped teeth about half the length of the tube.
Pods, ellipsoid-oblong, drooping from a slender stalk about as long (1-3 mm) as the calyx teeth, black appressed-hairy, membranous, 8-17 mm long, grooved below, almost 2-chambered, the partition sometimes nearly complete.

Source: The Illustrated Flora of British Columbia

Habitat / Range

Moist to mesic streambanks, river terraces, meadows, rocky slopes, heath, tundra and open forests in the montane to alpine zones; frequent in BC east of the Coast-Cascade Mountains; N to AK, YT and NT, E to NF and S to ID, MT, NM, NV, WA and NE OR.

Source: The Illustrated Flora of British Columbia


Ecological Framework for Astragalus alpinus

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class




Elevation (metres) 33 1805 2682
Slope Gradient (%) 0 27 100
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
10 171 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
0 2 6
Modal Nutrient Regime
Number of field plots
 species was recorded in:
Modal BEC Zone Class
All BEC Zones (# of stations/zone) species was recorded in: AT(42), BAFA(26), BWBS(10), ESSF(74), IMA(16), MH(12), MS(8), SBPS(5), SBS(1), SWB(12)


The climate type for this species, as reported in the: "British Columbia plant species codes and selected attributes. Version 6 Database" (Meidinger et al. 2008), is not evaluated, unknown or variable.

Taxonomic and Nomenclatural Links

Additional Photo Sources

General References