Astragalus is a large genus of about 3,000 species of herbs and small shrubs, belonging to the legume family Fabaceae and the subfamily Faboideae. It is the largest genus of plants in terms of described species. The genus is native to temperate regions of the Northern Hemisphere. Common names include milkvetch (most species), locoweed (in North America, some species) and goat's-thorn (A. gummifer, A. tragacanthus). Some pale-flowered vetches are similar in appearance, but vetches are more vine-like.