Arid, with a sparse cover of perennial grasses and shrubs including species of Artemisia, Anabasis, and Haloxylon. Perennial herbs include Achillea fragrantissima and Astragalus spp., as well as Stipagrostis plumosa. Fast-growing ephemeral herbs sprout after rains, and quickly set seed before succumbing to the summer drought. Populus euphratica, reeds, and bulrushes are found in the seasonal and permanent wetlands along the Tigris and Euphrates rivers.