Seas of grass
Temperate grasslands are found where the summers are hot, the winters cold, and rainfall is low throughout the year. Tropical grasslands grow where temperatures are relatively high all year round and rainfall occurs seasonally.
Grasslands are called different names in different parts of the world: - ‘steppes’ in Asia; ‘prairies’ in North America; ‘pampas’, ‘llanos’ and ‘cerrados’ in South America; ‘savannas’ and ‘velds’ in Africa; and ‘rangelands’ in Australia.
Keep on growing
Grasslands are dominated by grasses and grasslike plants. Grasses are very special plants that can keep on growing no matter how much they are nibbled by animals - because their growing points are situated low down near the soil.
Grasslands can therefore support a high density of grazing animals. Many grass species can grow back quickly after a fire has swept through the grassland, and some have seeds that can grow after being burned in a fire. Many grasslands in Australia, Africa and South America are maintained by fires.
Because grasses are wind-pollinated plants, their flowers tend to be small and modest compared to plants that need to attract insects for pollination.
Grasslands have other types of plants besides the true grasses. They have a number of herbaceous flowering plants and a variety of scattered trees and bushes.
Grasslands change their appearance throughout the year. In winter (or in the tropical dry season), grasslands look drab and lifeless. In the temperate grasslands, spring brings about a transformation as tender shoots emerge, the grass starts growing, and the first flowers bloom. A similar change is seen in tropical grasslands when the onset of the rainy season changes the landscape from dull brown to bright green.
The world's natural grasslands are fragile but dynamic ecosystems that are home to many uniquely adapted animals and plants. But most of the world's natural grasslands, including vast areas of the Russian steppes and American prairies, have been converted to wheat or corn fields. The East African savannas are facing similar threats.
Worldwide, grassland wildlife must compete with domestic livestock which are often kept in such high numbers that overgrazing and soil erosion occurs.
WWF works to ensure the world's remaining grasslands are protected. Among WWF's Global Ecoregions - the world's most important ecoregions - a number of grassland ecosystems are listed.