Description from Flora of China
Trees to 30 m tall. Branches grayish brown; branchlets tomentose. Buds ovoid, smooth, viscid. Petiole terete, ca. 4 cm, densely pubescent; leaf blade broadly ovate-cordate, ca. 10 × 8 cm, abaxially glaucous, with dense hairs, adaxially dull green, pilose along veins, base cordate, margin glandular serrulate, ciliate when young, apex acute. Fruiting catkin to 15 cm; rachis pubescent; bracts russet, suborbicular, laciniate. Disc sinuolate. Capsule ovoid, densely tomentose when young, glabrescent, 4-valved, subsessile. Fl. May, fr. Jul.
Similar to Populus ciliata but branchlets densely tomentose; petiole ca. 1/2 as long as leaf blade, eglandular distally; capsule subsessile, densely hairy when young. Similar also to P. lasiocarpa but petiole not red, smaller; leaf blade broadly ovate-cordate, smaller, ca. 10 cm, base cordate, apex acute; bracts suborbicular; disc sinuolate; capsule glabrescent, 4-valved.
* Mountain slopes, along rivers; 3000-3800 m. Xizang (Mainling Xian, Nyingchi Xian)