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兴隆县自2002年实施退耕还林以来,累计栽植杨树达5万余亩,其中95%为欧美107、108等速生品种,栽植后,树高和胸径生长速度极快,是本地的北京杨和加杨不能比的。但从2006年春季开始,
Since the implementation of the project of converting farmland to forest in 2002, Xinglong County has planted more than 50,000 acres of poplar trees, of which 95% are fast-growing varieties such as 107,108 in Europe and the United States. After planting, the tree height and DBH growth rate is very fast. Yang can not compare. However, starting from the spring of 2006,