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落羽松属为落叶或常绿乔木。树皮淡褐色。成长条片或鳞片状开裂;冬芽近园球形,芽鳞多数覆瓦状排列;小枝有两种,上部顶生枝宿存,下部侧生无芽小枝与叶同时脱落。叶互生,线形,扁平或锥形,螺旋状排列,柔软,绿色。花雌雄异花同株,雄花多数集生于下垂的枝梢上,形成穗状花序;雌花着生于小枝顶端,珠鳞数个,螺旋状互生,楯状隆起,每个珠鳞具2个胚珠;球果近园球形;种鳞木质,楯状,每种具种子2粒,种子为不规则三角形,具3个锐的鳞脊,子叶4-9枚。 本属在有史之前广布于欧洲和美洲,现存三种分布于北美洲:（1）落羽松（Taxodiumdistichum（L）Rich.（2）池柏（Taxodium ascendens Brongn.）,（3）墨西哥落羽松（Taxodium mucronatmg,Ten）。落羽松分布于新泽西州南部和特拉华州到佛罗里达州,西至阿肯色州和路易斯安那州,得克萨斯州,经密西西比河谷到来苏里州。池柏分布于弗吉里亚州到佛罗里达州和亚拉巴马。墨西哥落羽松原产墨西哥中部,特别在锡那罗亚州和科阿韦拉州;向北伸展到美国得克萨斯州西南部和危地马拉。落羽松属的木材轻软,不坚实,淡黑褐色,易于加工;供建筑,铁路枕木,码头枕木,篱笆柱子,桶材等;耐腐朽,与湿土接触保存良好。
Plumeria is a deciduous or evergreen tree. Bark pale brown. The growth of the strip or scale-like cracking; winter bud near the park spherical, bud scales most of the tile-like arrangement; there are two branches, the top of the top Zhizheng surviving, the lower side of the non-bud twig and leaves off at the same time. Leaves alternate, linear, flat or conical, spiral arrangement, soft, green. Flowers dioecious flower the same strain, most of the male flowers born in the drooping shoots to form spikes; female flowers were born in the twigs at the top, a few beads scales, spiral-shaped, ridge-like bulge, each with two pearl scales Ovules; cones nearly spherical; scales scales woody, glabrous, each with two seeds, the seeds are irregular triangles, with 3 sharp scales ridges, cotyledons 4-9. The genus is widely distributed in Europe and the Americas prior to its history. Three species exist in North America: (1) Taxodium distichum (L.) Rich. (2) Taxodium ascendens Brongn., (3) (Taxodium mucronatmg, Ten). Pinus tabulaeformis distributed in southern New Jersey and Delaware to Florida, west of Arkansas and Louisiana, Texas, the Mississippi Valley arrived in Surrey. To Florida and Alabama. The Mexican owl is native to central Mexico, particularly in Sinaloa and Coahuila; north to the southwest Texas and Guatemala. The wood of the Pinus is light and soft, not solid , Light brown, easy to process; for construction, railway sleepers, dock sleepers, fencing pillars, barrels, etc .; decay resistance, contact with wet soil well preserved.