《中国植物志》|| 红豆杉科 TAXACEAE S. F. Grey ||红豆杉族 Trib. TAXEAE Milchior et Werd. ||红豆杉属 Taxus Linn.

1.红豆杉属——Taxus Linn.
Linn. Gen. Pl. 312. 1737. Nr. 756.
常绿乔木或灌木；小枝不规则互生，基部有多数或少数宿存的芽鳞，稀全部脱落；冬芽芽鳞覆瓦状排列，背部纵脊明显或不明显。叶条形，螺旋状着生，基部扭转排成二列，直或镰状，下延生长，上面中脉隆起，下面有两条淡灰色、灰绿色或淡黄色的气孔带，叶内无树脂道。雌雄异株，球花单生叶腋；雄球花圆球形，有梗，基部具覆瓦状排列的苞片，雄蕊6-14枚，盾状，花药4-9,辐射排列；雌球花几无梗，基部有多数覆瓦状排列的苞片，上端2-3对苞片交叉对生，胚珠直立，单生于总花轴上部侧生短轴之顶端的苞腋，基部托以圆盘状的珠托，受精后珠托发育成肉质、杯状、红色的假种皮。种子坚果状，当年成熟，生于杯状肉质的假种皮中，稀生于近膜质盘状的种托（即未发育成肉质假种皮的珠托）之上，种脐明显，成熟时肉质假种皮红色，有短梗或几无梗；子叶2枚，发芽时出土。
本属模式种：欧洲红豆杉Taxus baccata Linn.
本属约11种，分布于北半球。我国有4种1变种。
本属木材的边材窄，与心材区别明显，无树脂道及树脂细胞，纹理均匀，结构细致，硬度大，防腐力强，韧性强。为优良的建筑、桥梁、家具、器材等用材。惟产量少，一般仅作细木加工、船桨、拱形制品、车旋、雕刻、乐器及箱板等用; 种子可榨油。叶常绿，深绿色，假种皮肉质红色，颇为美观，可作庭园树。
本属树种耐荫性强，在天然林中生长缓慢，分布星散，野生树木日渐减少。惟木材优良，宜选用造林，加强抚育管理，可促进其加速生长，以生产优良木材。

《云南植物志》|| 红豆杉科 Taxaceae nom. conserv. ||红豆杉科 Taxaceae nom. conserv. ||红豆杉属 Taxus Linn.

1．红豆杉属 Taxus Linn.
常绿乔木或灌木，树皮裂成窄长薄片或鳞片脱落；大枝斜展，小枝不规则互生；芽鳞多数，覆瓦状排列。叶螺旋状排列，条形，直伸或微弯，下延生长，上面中脉隆起，下面中脉两侧各有一条淡黄色或淡灰绿色气孔带；叶内无树脂道。雌雄异株，雌雄球花均单生叶腋；雄球花有雄蕊6—14，每雄蕊具2—9个花药；雌球花总花轴上部的侧生花轴顶端的苞腋单生1枚胚珠，胚珠基部托以圆盘状珠托。种子当年成熟，卵形或倒卵形，坚果状，种皮坚硬，革质，微有棱脊，种脐显著，着生于红色、肉质杯状的假种皮中，胚乳不皱；子叶2，发芽时出土。
11种，分布北半球。我国有4种，1变种；云南有2种，1变种。
均为耐荫树种，生长缓慢，常散生于沟边杂木林中。本属各种木材坚实美观，无树脂道及树脂细胞；可供细木工、船桨、雕刻、乐器及箱板等，为优良用材树种；又常栽为庭园观赏树。

《Flora of North America》|| Taxaceae || || Taxus

1. Taxus Linnaeus, Sp. Pl. 2: 1040. 1753; Gen. Pl. ed. 5, 462, 1754.

Yew [Latin name for yew]

Trees or shrubs dioecious or monoecious. Bark reddish brown, scaly. Branches ascending to drooping; twigs irregularly alternate, green or yellow-green when young, reddish brown in age. Leaves often appearing 2-ranked, flexible; stomates abaxial, in 2 broad, pale bands; apex soft-pointed, mucronate, not sharp to touch; resin canal absent. Pollen cones globose, yellowish, with 4--16 peltate sporophylls, each bearing 2--9 sporangia. Ovule 1. Seed maturing in 1 season, brown; aril scarlet to orange-scarlet, soft, mucilaginous, thick, cup-shaped, open at apex, exposing hard seed coat; albumen uniform. x = 12.

Species 6--10 (3 in the flora): mainly north temperate regions.

The species of Taxus , discouragingly similar, are more geographically than morphologically separable; they were all treated by R. K. F. Pilger (1903) as subspecies of T . baccata Linnaeus. Detailed study of the genus (not neglecting the cultivated representatives), including extensive fieldwork, is much needed and long overdue.

The foliage, bark, and seeds---but not the fleshy red aril---of most Taxus species are toxic due to the presence of taxine (M. R. Cooper and A. W. Johnson 1984; J. M. Kingsbury 1964); this alkaloid, however, was not found in T . brevifolia (I. Jones and E. V. Lynn 1933). Two Eurasian species, T . baccata Linnaeus (English yew) and T . cuspidata Siebold & Zuccarini (Japanese yew), are best known and documented for toxicity. Cattle have been poisoned by T . canadensis planted in British Columbia, but toxicity of T . brevifolia has not been conclusively recorded (J. M. Kingsbury 1964). Although horses, cattle, and humans have been poisoned by ingesting yew leaves and seeds, the fresh foliage of T . canadensis is browsed by deer, and that of T . brevifolia by moose.

The only other yew native to the New World is Taxus globosa Schlechtendahl of Mexico and Honduras. The Old World T . baccata Linnaeus and T . cuspidata Siebold & Zuccarini---and T . ´ media Rehder, the alleged hybrid between these two---are common in cultivation in the flora area.

Although no extralimital species of Taxus is naturalized in North America, spontaneous, immature (sapling) exotic yews have been noted in a very few localities in the northeastern United States within the range of Taxus canadensis . Apparently originating from seeds dispersed (probably by birds) from cultivated yews, these plants differ from T . canadensis in having typically erect (rather than sprawling) stems. Immature volunteer yews are, with the use of macromorphological characters and with our present knowledge, probably unidentifiable to species.

Although species of Taxus are much cultivated in the Pacific Northwest, spontaneous yews have not been recorded there away from cultivated individuals, in the vicinity of which (or under which) they may reseed. Should such volunteers be found, the shape of their leaf epidermal cells as viewed in cross section---wider than tall (rather than taller than wide) or ± isodiametric---may be used to distinguish them from T . brevifolia .

Anatomical features of the leaves of yews, helpful in identification of the species, have been contributed by R. W. Spjut (unpublished data).

SELECTED REFERENCES

Chadwick, L. C. and R. A. Keen. 1976. A study of the genus Taxus. Ohio Agric. Exp. Sta. Bull. 1086. Cooper, M. R. and A. W. Johnson. 1984. Poisonous Plants in Britain and Their Effects on Animals and Man. London. [Minist. Agric., Fisheries & Food Ref. Book 161.] Jones, I. and E. V. Lynn. 1933. Differences in species of Taxus. J. Amer. Pharm. Assoc. 22: 528--531. Keen, R. A. 1956. A Study of the Genus Taxus. Ph.D. thesis. Ohio State University. Keen, R. A. and L. C. Chadwick. 1955. Sex reversal in Taxus. Amer. Nurseryman 100(6): 13--14. Kingsbury, J. M. 1964. Poisonous Plants of the United States and Canada. Englewood Cliffs.

《Flora of China》|| Taxaceae || ||红豆杉属 Taxus

1. Taxus Linnaeus, Sp. Pl. 2: 1040. 1753.

红豆杉属 hong dou shan shu

Trees or shrubs evergreen, dioecious; branchlets irregularly alternate, basal part with few or several persistent or early deciduous bud scales; winter bud scales overlapping, with prominent or indistinct, longitudinal adaxial ridges. Leaves 2-ranked, spirally arranged, sessile, or shortly petiolate in Taxus cuspidata, linear, straight or falcate, decurrent, adaxial surface with raised midvein, abaxial surface with 2 pale gray, grayish blue, or pale yellow stomatal bands, resin canal absent. Reproductive structures axillary, solitary. Pollen cones pedicellate, globose, with overlapping bracts at base; microsporophylls 6-14, shield-shaped, each with 4-9 radially arranged pollen sacs. Seed-bearing structures subsessile, with several overlapping bracts, 2 or 3 distal pairs of which are decussate. Aril red or orange when ripe, succulent. Seed nutlike, ripening in 1st year, enclosed within cupular aril but with apex exposed; hilum prominent. Cotyledons 2. Germination epigeal. 2n = 24.

About nine species: mainly N hemisphere; three species in China.

Taxus sumatrana (Miquel) de Laubenfels (T. celebica (Warburg) H. L. Li), from Indonesia (Sulawesi and Sumatra) and the Philippines, has been recorded from China (e.g., Fl. Taiwan, ed. 2). Such records are based on a broad concept of that species, including the taxa treated in this account as T. wallichiana var. chinensis and T. wallichiana var. mairei (but excluding the type of T. wallichiana). The total number of distinct species of Taxus occurring in Asia is quite controversial and in need of further study.

The papillae and other characters of the abaxial leaf surface are best observed in fresh, young leaves. The papillae are minute and are best seen using a microscope or a lens of × 25 magnification or greater.