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杨树是张家口坝上高寒地区主要树种之一,杨树造林占现有林面积的97％以上。但是,由于气候寒冷,生长期短,多风,干早,加上土壤瘠薄,致使杨树生长慢。据调查,在尚义县南壕欠公社麦克阁滩,1958年春营造的杨树片林,到1975年满17年生的杨树,平均树高7米,胸径9厘米,只长成个椽材。据调查分析,除了杨树树种和立地条件差等因素外,造林后对杨树的修剪管理不及时,经营管理赶不上去也是一个主要原
Poplar is one of the main tree species in the alpine region of Zhangjiakou. Poplar planting accounts for over 97% of the existing forest area. However, due to the cold climate, short growing season, windy and dry weather, coupled with barren soil, the poplar grows slowly. According to the survey, in Shangyi County South Moor owed commune Mickey Beach, the spring of 1958 to create the poplar forest, to 1975, 17 years old poplar, the average tree height of 7 meters, 9 cm in diameter, only grow into a rafter . According to the survey and analysis, in addition to poplar tree species and poor site conditions and other factors, the pruning of afforestation after afforestation management is not timely, management can not keep up is also a major original