Astragalus purshii

Astragalus purshii is a wide-ranging perennial herb found in a variety of open habitats, including gravelly hillsides, clay or gullied bluffs, dunes, river terraces, valley flats, dry rushy meadows around lakeshores, open coniferous forests, sagebrush steppe and deserts, and bunchgrass steppe. It occurs in western North America, particularly in the Intermountain Region, from southwestern Canada in Saskatchewan west to British Columbia, south to southern California, Colorado, and South Dakota in the United States. There are over 1500 occurrences, which face threats from livestock grazing, recreational activities (especially off-road vehicles), and invasive species. Little is known about trends, but with a large range extent and large number of occurrences, abundant habitat, and broad habitat preferences, this species is considered secure.

Astragalus purshii occurs in western North America, particularly in the Intermountain Region, from southwestern Canada in Saskatchewan west to British Columbia, south to southern California, Colorado, and South Dakota in the United States (FNA 2023). Range extent was estimated to be over 2.3 million square kilometers using herbarium specimens and photo-based observations documented between 1994 and 2025 (RARECAT 2025, GBIF 2026, iNaturalist 2026, SEINet 2026).

By applying a 1 km separation distance to herbarium specimens and photo-based observations documented between 1994 and 2025, it is estimated that there are over 1500 occurrences rangewide (RARECAT 2025, GBIF 2026, iNaturalist 2026, SEINet 2026).

Although threats are not widely documented, this taxon is potentially threatened by conversion to agriculture, livestock grazing, recreational activities (especially off-road vehicles), and invasive species, though there is insufficient data, including anecdotal accounts, to understand scope and severity of threats for this taxon.