Astragalus (As-trá-ga-lus) is a large genus of about 2,000 species of herbs and small shrubs, belonging to the legume family Fabaceae, subfamily Faboideae. The genus is native to temperate regions of the Northern Hemisphere. Common names include milk-vetch (most species), locoweed (in western US) and goat's-thorn (A. gummifer, A. tragacanthus). Some pale-flowered vetches are similar in appearance, but vetches are more vine-like.
Astragalus species are used as food plants by the larvae of some Lepidoptera species including the following case-bearers of the genus Coleophora: C. astragalella (feeds exclusively on A. glycyphyllos), C. cartilaginella (feeds exclusively on Astragalus), C. colutella, C. euryaula (feeds exclusively on Astragalus), C. gallipennella (feeds exclusively on A. glycyphyllos), C. hippodromica (feeds exclusively on A. gombo), C. onobrychiella (feeds exclusively on Astragalus), C. polonicella (feeds exclusively on A. arenarius) and C. vicinella.
Astragalus propinquus (also known as Astragalus membranaceus) has a history of use as an herbal medicine, and the biotechnology firms Geron Corporation and TA Sciences have been working on deriving a telomerase activator from it.