《中国植物志》|| 杨柳科 SALICACEAE ||裸柱头柳组 Sect. Psilostigmatae Schneid. ||褐背柳 Salix daltoniana Andersson

146．褐背柳（西藏林芝）图版70：1-5
Salix daltoniana Anderss. in Journ. Linn. Soc. 4: 49. 1859; Hook. f. Fl. Brit. Ind. 5: 632. 1888; Schneid. in Sarg. Pl. Wils. 3: 115. 1916; Hao in Fedde, Rep. Beih. 93: 93. 1936, excl. pl. Yunnan et Sichuan;西藏植物名录, 45. 1980.
灌木或小乔木。幼枝被疏柔毛；小枝黑紫色。芽卵形，较叶柄短，黑紫色，有时有白粉。叶披针形、长圆形或椭圆形，长4.5-9厘米，宽1.5-2.5厘米，先端急尖，基部楔形至圆形，上面暗绿色，叶脉明显，侧脉11-14(8)对，无毛或仅脉上有短柔毛，幼叶散生柔毛，下面密被伏生的铅灰色绢毛，闪闪发光，叶脉不明显，多全缘，少有极不明显的细腺锯齿。花序有花序梗，梗上着生2-5小叶，花与叶同时开放；雄花序长3.5-6厘米，粗8-10毫米；雄蕊2，花药长圆形，黄色，花丝长4-5.5毫米，中下部有柔毛；苞片匙状长圆形，先端钝或近截形，全缘或有圆齿或2裂，黄褐色，外面有柔毛和长柔毛，内面无毛；腺体2,圆柱形；雌花序长4-6(7)厘米，粗5-6毫米，果序可达10厘米以上；子房卵形，密被柔毛，花柱约与子房等长，2深裂，柱头2裂，紫红色；苞片同雄花；腺体1，腹生，为苞片长的1/3-1/2。蒴果卵状圆锥形，渐狭，有毛或毛脱落，无柄或有短柄。花期5月下旬-6月上旬，果期7月。
产我国西藏（雅鲁藏布江流域）。生于海拔3000-4400米的山坡灌丛中。锡金、不丹、尼泊尔、印度也有分布。
本种与白背柳S. balfouriana Schheid.,银背柳S. ernesti Schneid.相似。主要区别为本种叶下面密被伏生的铅灰色绢毛，有光泽，至老叶毛也很少脱落，叶脉不明显，花柱及柱头不扭曲。

《Flora of China》|| Salicaceae || Salix ||褐背柳 Salix daltoniana

163. Salix daltoniana Andersson, J. Linn. Soc., Bot. 4: 49. 1860.

褐背柳 he bei liu

Shrubs or small trees. Branchlets blackish purple, sparsely downy when young. Buds ovoid, shorter than petiole, rarely pruinose. Petiole ca. 1 cm; leaf blade lanceolate, oblong, or elliptic, 4.5-9 × 1.5-2.5 cm, abaxially densely lead gray sericeous, shiny, adaxially dull green, glabrous or pubescent along veins, when young sparsely downy, base cuneate to rounded, margin entire, rarely indistinctly glandular serrulate, apex acute; lateral veins 11-14(-16) each side of adaxially conspicuous midvein; veins indistinct abaxially. Flowering coetaneous. Male catkin cylindric, 3.5-6 × 0.8-1 cm; peduncle with 2-5 leaflets; bracts yellowish brown, spatulate-oblong, abaxially downy and villous, adaxially glabrous, margin entire, crenate, or 2-cleft, apex obtuse or subtruncate. Male flower: stamens 4-5.5 mm, basally downy; anthers yellow, oblong. Female catkin 4-6(-7) cm × 5-6 mm, more than 10 cm in fruit; bracts as in male catkin. Female flower: gland adaxial, 1/3-1/2 as long as bracts; ovary ovoid, densely downy; style ca. as long as ovary, 2-lobed; stigma purplish red, 2-cleft. Capsule ovoid-conical, pilose or glabrescent, attenuate, sessile or shortly stipitate. Fl. May-Jun, fr. Jul. 2n = 38.

Thickets on mountain slopes; 3000-4400 m. Xizang [Bhutan, India, Nepal, Sikkim]

Similar to Salix balfouriana and S. ernestii but leaf blade densely lead gray sericeous, shiny, and indistinctly veined abaxially; style and stigma not twisted.