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云南引种桉树已有80多年的历史,引种后保存下来的桉树至今尚有60种以上,分布在118个县。据初步统计,小面积人工林1.5万亩,四旁植树五亿株,产叶桉油300吨左右。生长较好、种植较多的有兰桉、直干桉、赤桉、大叶桉、柠檬桉等十多种。特别是兰桉和直干桉是适应云南气候条件的优势树种,其生长速度大大超过原产地和国内其它省。四旁植树,10年生的直干桉平均高达23.2米、平均胸径32.4厘米(玉溪)、10年生兰桉平均高21.7米,平均胸径32.8厘米(保山)。如以17年生的蓝桉与保山当地同年生的速生树种相比较,其平均高生长量为杉木的246％,园柏的155％、银桦的121％,喜树的144％,楸木的194％;年平均直
Eucalyptus has been introduced for more than 80 years in Yunnan Province. Up to now, more than 60 eucalyptus species have been introduced and distributed in 118 counties. According to preliminary statistics, a small area of 1.5 million mu of plantation, planting five hundred million plants on all sides, leaves eucalyptus oil 300 tons. Good growth, planting more Eucalyptus, straight eucalyptus, Eucalyptus urophylla, Eucalyptus grandis, lemon eucalyptus and so on more than 10 kinds. In particular, Eucalyptus grandis and Eucalyptus urophylla are the dominant tree species that adapt to the climatic conditions in Yunnan and their growth rate greatly exceeds that of their origin and other provinces in China. Tree planting on all four sides, 10-year-old straight dry eucalyptus averaging up to 23.2 meters, an average diameter of 32.4 cm (Yuxi), 10-year-old Eucalyptus an average of 21.7 meters high, average diameter of 32.8 cm (Baoshan). For example, the average high growth rate of 17-year-old blue eucalyptus and the native perennial species of Baoshan is 246% of Chinese fir, 155% of park cypress, 121% of silver birch, 144% of Camptotheca acuminata, 194 %; Average annual straight