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北京市市区有2万多株古树。据1988年第三次古树普查,仅北京市内及近郊就有300年以上树龄的一级古树3804株,百年以上的古树19723株,如加上远郊区县的古树约50000株左右。(古树的树龄必须超过100年,300年以上的为一级古树,100年以上的为二级古树。但古树并不仅仅只是老树,老树是指存活时间长的树木,有可能就长在深山老林,自生自灭。)它们大多种植在辽金时期至明清两代,最早的可以追溯到汉唐。其树种主要是常绿的柏树、松树和落叶的银杏、槐树、枣树等。
There are more than 20,000 ancient trees in Beijing’s urban area. According to the third ancient tree census in 1988, there were 3804 first-class ancient trees with an age of over 300 years and 19723 old trees with a century-long history in Beijing and its suburbs alone. For example, about 50,000 ancient trees with suburban districts and counties about. (The old tree must be more than 100 years old, more than 300 years old as an ancient tree, and more than 100 years as a second-class ancient tree.) However, the old tree is not just an old tree, It is possible to grow in deep forests, fend for themselves.) Most of them planted in the Liao and Jin dynasties to the Ming and Qing dynasties, the earliest can be traced back to the Han and Tang dynasties. The tree species are mainly evergreen cypress, pine and deciduous ginkgo, locust tree, jujube and so on.