文县杨 wen xian yang

Trees to 30 m tall; trunk straight, to 80 cm d.b.h.; bark gray-green or green-white, smooth, that of old trunk shallowly furrowed at base. Sprouts and long branchlets angled. Leaves on short branchlets with petiole terete, 3-5 cm, laterally flattened distally; leaf blade ovate-orbicular or rhombic-ovate, 6-10 × 2.5-8 cm, abaxially greenish white, adaxially dull green, base rounded or broadly cuneate, margin with glandular teeth, apex acuminate. Leaf blade of sprouts and long branchlets deltoid-ovate or broadly ovate, 11-18 × 7-12 cm, base subcordate, rounded or broadly cuneate, margin with obtusely glandular teeth. Male catkin 4-5 cm; rachis glabrous. Fruiting catkin 8-12 cm; bracts fan-shaped, 2-2.5 mm, intricately laciniate. Female flower: ovary glabrous; stigma large, 3-lobed. Capsule long ovoid, 4-7 mm, (2 or)3-valved; stipe ca. 1 mm. Fl. Apr, fr. May.

* Mountains, along rivers; 1200-1800 m. Gansu (Wen Xian)