针叶是裸子植物常见的叶子外形。 横切面结构针叶的最外层为表皮(Epidermis)，而内面紧接有一层皮下层(Hypodermis)。表层细胞强木质化，表面上有很厚的角质层。表皮上有稀疏的气孔器，而且气孔器明显下陷。
中国最大的综合性文献数据库 -维普资讯 关键词: 松科 针叶 形态特征 解剖学特征[gap=1013]Key words: Pinaceae; needles; morphological character; anatomical structure
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针叶树 [林] conifer ; [林] coniferous tree ; needle leave tree ; cypress
北方针叶林 [林] taiga ; [林] boreal coniferous forest ; boreal forest ; boreal conif
针叶林 taiga forest regions
温带针叶林 temperate coniferous forest
披针叶杜英 Elaeocarpus lanceifolius
倒披针叶虫实 Corispermum lehmannianum ; lehmannianum bunge
针叶天蓝绣球 Phlox subulata
针叶树种 [林] coniferous species ; coniferous
针叶苋属 Trichurus ; Trichurus C.C.Townsend
现在（大家）想象一棵布满了密密麻麻的小针叶的松树。
Now imagine a pine tree with all those little densely packed needles.
人们对森林衰退还知之甚少，但森林衰退会导致树叶和针叶大面积脱落。
Forest decline is still poorly understood but leads to the loss of a high proportion of a tree's needles or leaves.
通过吮吸铁杉幼嫩枝的汁液，树木的生长被毛茸茸的叶蝉阻碍，导致针叶从深绿色变为灰绿色，并提早掉落。
By sucking sap from the young twigs of the hemlock tree, tree growth is retarded by the woolly adelgid, causing needles to change color from deep green to grayish green and to drop prematurely.
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