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迎春５号杨是牡丹江林区１９８２年从中国林科院引进的黑小杨混合系中选育出的优良无性系。该品种具有生长迅速、材质优良、抗性强等优良特性。１５年生林分平均胸径达３０１ｃｍ、平均树高达２０１ｍ、单株材积０５１４９ｍ３，显著超过了小黑杨等参试品种。根据树冠面积与胸径相关关系选择数学模型进行拟合，得到ｙ＝ａ＋ｂｘ＋ｃｘ２＋ｄｘ３为最佳模型，以此编制迎春５号杨经营密度表。
Yingchun 5 Yang is Mudanjiang forest in 1982 from the Chinese Academy of Forestry introduced Xiao-Yang hybrid system in the fine cloned. The variety has the rapid growth, excellent material, resistance and other excellent characteristics. The average DBH of 15-year-old stands was 301 cm, the average tree height was 201 m, and the single plant volume was 0. 549 m 3, which significantly surpassed the tested cultivars such as Populus simonii. According to the relation between canopy crown area and DBH, the mathematical model was selected for fitting, and y = a + bx + cx2 + dx3 was the best model.