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我场侧柏具有树干通直、园满,树冠呈尖塔形或尖园锥形、冠幅小,适于密植,生长较快,病虫害少的特点。据省林木良种繁育调查组72年7月份的调查,在土层深30—40厘米,碎石含量40—50％的立地条件下,20年生侧柏平均高7.5米,胸径9.8厘米,最大植株树高9.8米,胸径13.5厘米,每亩蓄积量3立方米(林分密度稳),是一种优良类型。为了加速这种侧柏优良类型的繁殖,我们选择了生长较好的林分,建立母树林。
My field Arborvitae has trunk straight, garden full, crown was pointed tower or cone tip park, small crown, suitable for close planting, rapid growth, fewer pests and diseases. According to the survey conducted by the Provincial Forest Breeding and Breeding Investigation Team in July, 72, the average annual height of 20-year-old Platycladus orientalis was 7.5 meters and the diameter at breast height was 9.8 centimeters under the site conditions of 30-40 cm deep and 40-50% 9.8 meters high, 13.5 cm in diameter at breast height, 3 cubic meters per acre (stand density density), is a good type. In order to speed up this excellent type of Arborvitae breeding, we have chosen to grow better stand, the establishment of the parent forest.