《中国植物志》|| 杨柳科 SALICACEAE ||白杨组 Sect. Populus ||银白杨 Populus alba L.

1．银白杨（中国树木分类学）
Populus alba L. Sp. Pl. 1034. 1753; Schneid. in Sarg. Pl. Wils. 3: 37. 1916; Rehd. Man. Cult. Trees and Shrubs 84. 1927; Hao in Contr. Inst. Bot. Nat. Acad. Peiping 3: 227. 1935; Kom. Fl. URSS, 5: 225. 1936;陈嵘, 中国树木分类学, 112. 1937; 刘慎谔等, 东北木本植物图志, 112.图版9: 1-2. 图版12: 32. 1935; Poljak. in Fl. Kazakhst. 3: 40. 1960;中国高等植物图鉴, 1: 350. 图700. 1972; 秦岭植物志, 1 (2): 16. 1974; 西藏植物名录, 43. 1980.
乔木，高15-30米。树干不直，雌株更歪斜；树冠宽阔。树皮白色至灰白色，平滑，下部常粗糙。小枝初被白色绒毛，萌条密被绒毛，圆筒形，灰绿或淡褐色。芽卵圆形，长4-5毫米，先端渐尖，密被白绒毛，后局部或全部脱落，棕褐色，有光泽；萌枝和长枝叶卵圆形，掌状3-5浅裂，长4-10厘米，宽3-8厘米，裂片先端钝尖，基部阔楔形、圆形或平截，或近心形，中裂片远大于侧裂片，边缘呈不规则凹缺，侧裂片几呈钝角开展，不裂或凹缺状浅裂，初时两面被白绒毛，后上面脱落；短枝叶较小，长4-8厘米，宽2-5厘米，卵圆形或椭圆状卵形，先端钝尖，基部阔楔形、圆形，少微心形或平截，边缘有不规则且不对称的钝齿牙；上面光滑，下面被白色绒毛；叶柄短于或等于叶片，略侧扁，被白绒毛。雄花序长3-6厘米；花序轴有毛，苞片膜质，宽椭圆形，长约3毫米，边缘有不规则齿牙和长毛；花盘有短梗，宽椭圆形，歪斜；雄蕊8-10，花丝细长，花药紫红色; 雌花序长5-10厘米，花序轴有毛，雌蕊具短柄，花柱短，柱头2,有淡黄色长裂片。蒴果细圆锥形，长约5毫米，2瓣裂，无毛。花期4-5月，果期5月。
辽宁南部、山东、河南、河北、山西、陕西、宁夏、甘肃、青海等省区栽培，仅新疆（额尔齐斯河）有野生。欧洲、北非、亚洲西部和北部也有分布。模式标本采自欧洲。
银白杨喜大陆性气候，耐寒，深根性，根薛力强，抗风力强，对土壤条件要求不严，但以湿润肥沃的沙质土生长良好。不耐湿热，北京以南地区栽培的多受病虫害。用种子和插条繁殖。种子千粒重0.54克，发芽率95%。插条育苗时，将枝条进行冬季沙藏，保持0-5摄氏度的低温，促使皮层软化，或早春将剪好的插穗放入冷水中浸5-10小时，再用湿沙分层复盖，经5-10天后扦插，也可用生长素处理。银白杨木材纹理直，结构细，质轻软，可供建筑、家具、造纸等用。树皮可制栲胶；叶磨碎可驱臭虫；树形高耸，枝叶美观，幼叶红艳，可做绿化树种。也为西北地区平原沙荒造林树种。

《Flora of China》|| Salicaceae || Populus ||银白杨 Populus alba

1. Populus alba Linnaeus, Sp. Pl. 2: 1034. 1753.

银白杨 yin bai yang

Trees to 30 m tall, suckering freely; crown broad. Branchlets at first white tomentose; shoots grayish green or brownish, terete, densely white tomentose. Buds russet, ovoid, 4-5 mm, densely white tomentose, glabrescent, shiny. Leaves of short branchlets with petiole slightly flattened, ca. as long as leaf blade; leaf blade ovate-orbicular or elliptic-ovate, 4-8 × 2-5 cm, both surfaces tomentose. Leaves of sprouts and long shoots ovate-orbicular, middle lobe much larger than lateral ones, 4-10 × 3-8 cm, adaxially white tomentose at first, somewhat glabrescent, base broadly cuneate, rounded, truncate, or subcordate, palmately 3-5-lobed; margin irregularly notched; lateral lobes spreading nearly obtusely, entire or notched-lobed. Male catkin 3-6 cm. Male flower: stamens 8-10. Female catkin 5-10 cm. Female flower: stipe short; stigma 2-lobed. Capsule narrowly conical, ca. 5 mm, glabrous, 2-valved. Fl. Apr-May, fr. May.

Native in Xinjiang; planted in Gansu, Hebei, Henan, Liaoning, Nei Mongol, Ningxia, Qinghai, Shaanxi, Shandong, Shanxi, Xinjiang [N Africa, SW and WC Asia, Europe].