Astragalus iodanthus
Humboldt river milkvetch
(c) Jim Morefield, some rights reserved (CC BY) · licence
Family: Fabaceae · Type: Herb · Native
Astragalus iodanthus (Humboldt river milkvetch) is a native California herb in the Fabaceae family.
Humboldt river milkvetch is a California native perennial herb found in foothill and mountain regions at moderate elevations. Flowering from May to July, this plant produces red-purple to cream-colored flowers with white and purple keel tips, arranged in clusters of 7 to 25 blossoms. Growing with several prostrate stems 5 to 40 centimeters long and few branches, it spreads in a low, delicate form across its habitat. Its compound leaves feature 9 to 21 widely obovate or rounded leaflets, each 3 to 18 millimeters long with blunt or slightly notched tips. The distinctive fruit develops as a pendulous pod 20 to 40 millimeters long, which becomes mottled and firm with age, often curving in a quarter to full circle.
Habitat and range
California counties: Lassen, Mono
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 native to California?
Yes. Astragalus iodanthus is native to California (recorded as native).
Where in California does Astragalus iodanthus grow?
Astragalus iodanthus occurs in Lassen, Mono.
What plant family does Astragalus iodanthus belong to?
Astragalus iodanthus is in the Fabaceae family, genus Astragalus.
Related species
Other California species in the same genus, family, or bioregion.
- Astragalus iodanthus var. diaphanoides — Snake milkvetch
- Astragalus iodanthus var. iodanthus — Humboldt river milkvetch
- Astragalus jaegerianus — Lane mountain milkvetch
- Astragalus johannis-howellii — Long valley milkvetch
- Astragalus kentrophyta — Kentrophyta milkvetch
- Astragalus kentrophyta var. danaus — Sweetwater mountains 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.