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a grazing animal bites off their leaves, grasses continue to grow from a central bud very close to the ground, fuelled by under- ground food stores. Being cut off near the ground actually stim- ulates grass to grow, as anyone will know who has a lawn to look after. This enables grasslands to flourish when it is being heavily grazed, or after being burned. In the tropics, grasses grow during and shortly after the rains, or in some places in the short time when the ground is not flooded. In temperate regions grasses grow best in the spring, between a cool, wet winter and a hot, dry summer. Where the summers are not so hot or dry, as in much of Europe, grasses grow throughout the summer months. As soon as conditions are right, they use their underground energy stores to produce shoots, grow fast, flower and produce seeds. When the seeds have ripened and been dispersed, and if the grass has not been cropped by grazing animals, the top materi- al dies back, leaving the ground covered in a ‘thatch’ of dead grass. Left alone, this would smother new growth in the follow- ing season, and slow down the warming of the ground by spring sunshine in temperate regions. In wild grassland, autumn fires clear away the thatch. Where Grasslands Are Found Grasslands can grow in a broad range of climates. Climate also affects the way in which people use grasslands. As well as the temperate prairies and the tropical savannahs, there are some very specialized grasslands dotted round the world. Typical grassland spreads across rolling or flat country, away from the coast, in areas with moderate rainfall. Tropical

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