Astragalus platytropis
Broad-keeled milkvetch
(c) Steve Matson, some rights reserved (CC BY) · licence
Family: Fabaceae · Type: Subshrub · Native
Conservation status: CNPS 2B.2
Astragalus platytropis (Broad-keeled milkvetch) is a native California subshrub in the Fabaceae family, recognized by high elevation cushion form and flattened fruits.
Broad-keeled milkvetch is a rare (CNPS 2B.2) California native perennial found in central Sierra Nevada, Sierra Nevada eastern slope, and Desert Mountains on rocky hilltops, ridges, and forest areas to above timberline at elevations of 2,350 to 3,500 meters. Flowering from July to August, this plant produces white to pale purple flowers in small head-like clusters with 4 to 9 blossoms. Growing as a dense, clustered herb with stems less than 2 centimeters tall, it features silvery or gray dense hairs. Its leaves are compound with 5 to 15 elliptic to obovate leaflets, each 4 to 11 millimeters long with generally blunt tips. The fruit is an ascending, bladdery pod 15 to 33 millimeters long, with purple-speckled valves that turn brown with age.
Identification and appearance
Key characters: 83 sympatric species; key features are high elevation cushion form and flattened fruits
Habitat and range
Habitat: Rocky hilltops, ridges, forest to above timberline
Elevation: 2350-3500 m
California counties: Inyo, Mono, Tuolumne
Outside California: to Oregon, Montana, Nevada
Bloom period
Astragalus platytropis blooms Jul-Aug.
Conservation status
CNPS 2B.2
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 platytropis native to California?
Yes. Astragalus platytropis is native to California (recorded as native).
When does Astragalus platytropis bloom?
Astragalus platytropis blooms Jul-Aug.
Where in California does Astragalus platytropis grow?
Astragalus platytropis occurs in Inyo, Mono, Tuolumne, at elevations of 2350-3500 m.
What plant family does Astragalus platytropis belong to?
Astragalus platytropis is in the Fabaceae family, genus Astragalus.
Is Astragalus platytropis rare or endangered?
Astragalus platytropis carries California Rare Plant Rank 2B.2, state rank S3.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
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.