Hầu hết các cơn mưa rơi vào mùa hè. Pampa đông nhận được trung bình 39 inch ( mm) lượng mưa năm và đất của nó là màu mỡ. Buenos Aires có trung bình 37 inch (940 mm) mưa một năm. | 12 GRASSLANDS Its most famous native grass is pampas grass which is grown ornamentally in many parts of the world but has become a very invasive weed in other regions including California Hawaii and New Zealand. Also known as silver pampas grass and Uruguayan pampas grass Cortaderia sell-oana this grass grows in dense tussocks eight to 12 feet m tall and produces large feathery flowers. Over large areas of the pampa silver pampas grass crowds out all other plants except for the herbs that grow between its tussocks. It is used to make paper but it is of little use for pasture. More nutritious pasture grasses and herbs have been sown to replace most of it. There are few trees in the eastern pampa because they cannot tolerate the frequent winter fires that are fanned by the strong perpetual winds. The grasses recover quickly from fire and benefit from the nutrients in the wood ash that the rain soon washes down to their roots. The one woody plant that does withstand fire is called the ombu Phytolacca dioica . It grows to a height of 40-60 feet 12-18 m and its girth the trunk circumference measured about four feet m above ground level can reach 40-50 feet 12-15 m . The plant often produces many trunks growing side by side. Technically this structure makes it a shrub rather than a tree despite its height. The ombu s trunk is spongy because it contains tissues that store water making it fire-resistant. Its ability to store water also helps it survive drought. Gauchos nicknamed these plants lighthouses because they are visible from afar and the umbrella-shaped top offers shade on a hot sunny day. Ombus are planted as shade trees in places with a suitable climate such as Southern California. Veld Grasslands known as the veld or grassveld cover the high plateau that occupies the eastern side of South Africa. Veld is the Afrikaans word for field. The elevation varies from approximately sea level to more than 9 000 feet 2 745 m . The veld extends over most of the
