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沙兰扬(Populus×euramericana)于1954年从东德引入我国.通过二十多年来各地的栽植试验,它的突出优点是生长快,成材早.如国营焦作林场加禾屯林区1975年营造的沙兰杨丰产林,现在林木平均高16米,平均胸高直径28厘米,单株材积0.4950立方米,每亩蓄积量17.82立方米.在生长前期,胸径生长量是同龄毛白杨的2.4倍.但是,不适地适树加强抚育管理树木就容易形成“小老树”.同一树种,有的在短时间内已成为参天大树,有的却始终造林不成材,这就存在
Populus × euramericana was introduced into our country from East Germany in 1954. Its remarkable merit is that it grows faster and gets better as early as planting planted in more than two decades. To create a high-yielding forest of Sallam Yang, now the average height of 16 meters of trees, the average height of 28 cm in diameter, single plant volume of 0.4950 cubic meters, 17.82 cubic meters per acre volume in the growth of DBH growth was 2.4 times the same age Poplar However, unsuitable to strengthen the tree management and tending to facilitate the formation of The same species, some have become towering trees in a short period of time, while others have been reforestation, it exists