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六盘山天然林中没有落叶松,只零星分布有华山松、油松。1964年开始,在二龙河林场引种华北落叶松育苗,初获成效。1967年开始造林,目前已有小面积成林。经调查,它生长迅速,树干通直。67～68年营造的落叶松平均生长高度8米以上,胸径13厘米,是六盘山林区营造用材林基地的好树种。落叶松虽然造林容易成活,但育苗中易受病害造成幼苗大量死亡。据近年来调查统
There is no larch in the natural forest of Liupan Mountain, only Huaxia Pine and Pinus tabulaeformis are scattered in the forest. Beginning in 1964, introduction of Larix principis-rupprechtii nursery seedlings at the Erlonghe Forest Farm was initially successful. Beginning of reforestation in 1967, there are already a small area of forest. After investigation, it grows rapidly, trunk straight. 67 to 68 years to create an average height of larch growth of 8 meters above sea level, diameter 13 cm, is Liupanshan forest timber base to create a good species. Although Larix afforestation is easy to survive, but nursery susceptible to disease caused a large number of seedlings died. According to surveys in recent years