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前言 雪松Gedrvs deodara(Roxb)Lowd是松科,雪松属的常绿大乔木,主干耸直,侧枝平展,树冠若塔,姿态优美,为世界著名的观赏树,也是优良的用材树种。 雪松原产喜马拉雅山西北部,我国西藏西南部亦有野生,分布于海拔1200—3000米地带,在1650—2400米处组成纯林或混交林。原产地至今尚有树高75米,直径4.3米的大树。寿命可达七、八百年。 雪松性喜土层深厚,排水良好的土壤,也能适应瘠薄砾石土壤,耐干旱,不耐水湿,耐寒力较强,在南京-13℃的低温安全无恙,1954年冬气温短时间降至-17℃时也未受害。 南京引种雪松已有50余年历史。雪松幼龄阶段生长较慢,20年后生长转快。中山陵园50余年生的大树高17.2米,胸径93.6厘米。玄武湖45年生的大树高达15米,胸径72厘米,材积约为3立方米。 雪松材质坚硬,纹理通直,经久耐用,易于加工,为建筑、造桥、枕木、造船和制作家
Preface Cedar Gedrvs deodara (Roxb) Lowd is an evergreen tree of Pinaceae and cedar with its main trunk rising upright, flat branches and towering crown. It is a world famous ornamental tree and is also an excellent tree species. Cedar native to the northwestern Himalayas, southwestern Tibet also has wild, distributed in the 1200-3000 meters above sea level, composed of pure forests or mixed forests at 1650-2400 meters. Origin so far there are trees 75 meters high, 4.3 meters in diameter trees. Life expectancy up to seven or eight years. Cedar loving hi soil deep, well drained soil, but also to adapt to infertile gravel soil, drought-resistant, water-resistant wet, strong cold hardiness, low temperature in Nanjing -13 ℃ safe, short winter temperature in 1954 dropped to - 17 ℃ also not affected. Cedar introduced in Nanjing has more than 50 years of history. Cedar young stage of growth is slower, faster growth after 20 years. Zhongshan cemetery more than 50 years old tree height 17.2 meters, diameter 93.6 cm. 45-year-old trees Xuanwu Lake tree up to 15 meters, diameter 72 cm, volume of about 3 cubic meters. Cedar material is hard, straight texture, durable, easy to process, for construction, bridge construction, sleepers, shipbuilding and fabricators