Cool deserts and semi-deserts occur on cool temperate plains and plateaus in central Eurasia and temperate parts of the Americas from sea level up to 4,000 m. Strong winds and freezing temperatures prevail, with low annual precipitation falling as winter snow or sleet. Productivity is low on infertile sandy and clay soils, often with high salinity. Vegetation comprises a sparse cover of low grasses and dwarf shrubs, interspersed with bare patches, with some areas having only lichens and mosses or no vegetation at all. Fauna includes large nomadic herbivores including antelopes, wild horses and camels, which control composition of vegetation. Predators include raptors, snakes, bears, and cats.