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加杨(P.Canadensis Moenh)是温带耐中温较耐寒树种,具有速生和对土壤气候要求不高、适应性较强的特性。1980年夏我们在北京潮白河林场进行小班人工林森林资源调查中,为了了解现有加杨人工林由于地形部位的差
P.Canadensis Moenh is a temperate, moderate-temperature and hard-cold species, which has the characteristics of fast growing and less demanding on the soil and climate. 1980 summer we Chaobaihe forest farm in Beijing small forest plantation survey, in order to understand the existing poplar plantation due to differences in the topography