Astragalus iodanthus var. iodanthus
Humboldt river milkvetch, Humboldt River Milkvetch
(c) Jim Morefield, some rights reserved (CC BY) · licence
Family: Fabaceae · Type: Herb · Native
Astragalus iodanthus var. iodanthus (Humboldt river milkvetch) is a native California herb in the Fabaceae family, recognized by other varieties by hairlessness and keel position.
Humboldt river milkvetch is a California native perennial found in the southeastern Sierra Nevada in Mono County, inhabiting hillsides and valley floors with sagebrush at elevations of 1,300 to 2,600 meters. Flowering from April to June, this plant produces small flowers with keel petals barely extending beyond the wing petals. Growing with a generally glabrous stem structure, it reaches moderate height in its sagebrush habitat. Its leaves are compound, typical of milkvetch species, with multiple leaflets arranged along slender stems. The plant's smooth appearance and subtle floral structure distinguish it in the sparse sagebrush landscapes of eastern California.
Identification and appearance
Key characters: 36 sympatric species; distinguished from other varieties by hairlessness and keel position
Habitat and range
Habitat: Hillsides, valley floors, generally with sagebrush
Elevation: 1300-2600 m
California counties: Mono, San Bernardino, Lassen
Outside California: to Oregon, Idaho, Utah
Bloom period
Astragalus iodanthus var. iodanthus blooms Apr-Jun.
How to tell it apart
vs Vicia: Astragalus has racemes of flowers; vetches (Vicia) have tendrils at leaf tips and climbing or sprawling habit.; vs Oxytropis: Astragalus keel tip is rounded to slightly pointed; Oxytropis keel has a pronounced pointed beak.; vs Cleomella: Astragalus has pea-shaped flowers; Cleomella has 4-petaled cruciform flowers with long stamens.; vs Lupinus: Astragalus has pinnate compound leaves; lupines have palmate leaves (leaflets radiating from one point).; vs Dalea: Astragalus has typical pea flowers; Dalea has tiny flowers with petals attached to the stamen tube.
Frequently asked questions
Is Astragalus iodanthus var. iodanthus native to California?
Yes. Astragalus iodanthus var. iodanthus is native to California (recorded as native).
When does Astragalus iodanthus var. iodanthus bloom?
Astragalus iodanthus var. iodanthus blooms Apr-Jun.
Where in California does Astragalus iodanthus var. iodanthus grow?
Astragalus iodanthus var. iodanthus occurs in Mono, San Bernardino, Lassen, at elevations of 1300-2600 m.
What plant family does Astragalus iodanthus var. iodanthus belong to?
Astragalus iodanthus var. iodanthus is in the Fabaceae family, genus Astragalus.
What habitat does Astragalus iodanthus var. iodanthus grow in?
Astragalus iodanthus var. iodanthus grows in Hillsides, valley floors, generally with sagebrush.
Related species
Other California species in the same genus, family, or bioregion.
- Astragalus jaegerianus — Lane mountain milkvetch
- Astragalus johannis-howellii — Long valley milkvetch
- Astragalus kentrophyta — Kentrophyta milkvetch
- Astragalus kentrophyta var. danaus — Sweetwater mountains milkvetch
- Astragalus kentrophyta var. elatus — Spiny-leaved milkvetch
- Astragalus kentrophyta var. tegetarius — Mat milkvetch
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.