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我省秦巴地区主要桦木有白桦、红桦、糙皮桦、亮叶桦、坚桦,生长优势地段在海拔1200～2000米之间,常与华山松、油松、冷杉、云杉、铁杉、山杨、山柏、杨、栎类等相混生,也容易形成大面积纯林林分。该树种喜光,耐高寒气候和湿地瘠土。不择土壤,适应性很强,天然更新良好,是中、高山最有代表性的速生树种,也是中、高山地区育苗造林的理想树种,特别是与针叶林树种混交,具有能减少病虫害,有利于防止森林火灾的两大优点。 桦木因其树冠高大,果实很小,千粒重仅0.25克,且易分散,故而种子很难采集,即使少数能采集的地方,采时成本很高,同时十分
The main birch in Qinba area of our province are birch, red birch, rough birch, bright birch, and birch birch. The growth predominance is between 1200 and 2000 meters above sea level, often with Pinus armandii, Pinus tabulaeformis, fir, spruce, iron Cunninghamia lanceolata, mountain cypress, Yang, oak and other mixed, but also easy to form a large area of pure forest stand. The species hi light, cold climate and wetlands infertile. It is an ideal tree species for seedling and afforestation in middle and high mountains, especially mixed with coniferous tree species. It has the advantages of reducing pests and diseases, Benefit to prevent two major advantages of forest fires. Birch because of its tall canopy, the fruit is very small, only one thousand grain weight of only 0.25 grams, and easy to disperse, it is difficult to collect seeds, even if a few can be collected, the acquisition cost is high, while very