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优良防风固沙树种樟子松在榆林地区引种成功。据调查,1964年在榆林红石峡8米深沙层的沙地上栽植的樟子松,目前平均高2.5米,地径8.5厘米,未发现病虫危害,也没有寒害和冻害现象,树势健旺,生长良好。榆林地区是1956年开始从东北引进樟子松的。开初,由于他们对这一树种的特性认识不足,违背了自然规律,育苗造林几乎全部失败。后来,他们不断总结经验,改进技
Excellent windbreak sand species Pinus sylvestris introduced in Yulin area success. According to the survey, the Pinus sylvestris planted on the sandy ground of 8m deep sand layer in Hongshixia of Yulin in 1964 is an average of 2.5 meters high with an average diameter of 8.5cm. No pests and diseases were found and no cold damage or frost damage was found. Healthy, good growth. Yulin area is the introduction of Pinus sylvestris from the northeast in 1956. In the beginning, because of their lack of understanding of the characteristics of this species and violation of the laws of nature, almost all of them failed. Later, they constantly sum up their experience and improve their skills