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落羽松属有三种,即落羽松、池柏和墨西哥落羽松。前两种产美国南部,后一种产墨西哥。在墨西哥的渥撤卡地方有一株大树,树高42.6米,胸径11.7米,据估计树龄为4,000-5,000年。这三种树均为速生树种,其生长速度约与水杉相同或超过水杉,干形通直,木材质地比较轻软,可供建筑及家具之用,其最大特点是耐水湿,在积水1-3个月的情况下,尚能生长。在我国长江中、下游及南方水网地区发展落羽松是很有前途的。落羽松和池柏我国引种较早,多栽培在江南各城市,生长良好,深受平原水网地区农民群众的欢迎。1962年我们在南京工学院科学馆前观察到一独株墨西哥落羽松,树高21米,胸径80厘米,约40年生,每年开有大量的雌花和雄花,经过多年观察,从没见到果
There are three types of Pinus pluvialis, namely Pinus pluvialis, Bald cypress and Mexican bald pine. The first two are from the southern United States and the latter from Mexico. In Otzka, Mexico, there is a large tree with a tree height of 42.6 meters and a breast diameter of 11.7 meters, estimated to be between 4,000 and 5,000 years old. These three kinds of trees are fast-growing tree species, its growth rate is about the same with Metasequoia or more than Metasequoia, dry straight, relatively soft wood texture, for construction and furniture purposes, the most prominent feature is water-wet, in the water 1 -3 months, still able to grow. It is very promising for the development of Pinus tabulaeformis in the middle and lower reaches of the Yangtze River and the water network in the south. Bald Cypress and Bald Cypress introduced earlier in our country, and more cultivated in various cities of the south of Jiangnan. They grew well and were well received by farmers in plain water network. In 1962 we observed in front of the Science Museum of Nanjing Institute of Technology a single strain of Mexican plumeria, tree 21 meters high, diameter 80 cm, about 40 years old, each year a large number of female flowers and male flowers, after years of observation, never see fruit