Clematis potaninii Maxim.

Vines woody. Branches shallowly 5- or 6-grooved, appressed puberulous. Leaves usually (1 or)2-pinnate; petiole 3--5 cm; leaflet blades ovate to broadly ovate, 1.5--6 × 0.8--5.5 cm, thin papery, both surfaces sparsely appressed puberulous, base broadly cuneate, rounded, or subcordate, margin serrate, apex acute to acuminate; basal veins flat. Cymes arising from axils of leaves on current year’s branches, 1--3(or 4)-flowered; peduncle 5.5--15 cm; bracts ternate or simple, 3-lobed. Flowers 3--7 cm in diam. Pedicel 3--9.8 cm, appressed puberulous. Sepals 5 or 6(or 7), white, cuneate-obovate to narrowly obovate, 1.8--3.8 × 0.8--2.4 cm, abaxially densely appressed puberulous, adaxially glabrous, apex rounded and apiculate. Stamens 0.7--1.8 cm, glabrous; anthers narrowly oblong, 2--3 mm, apex obtuse. Ovaries pubescent. Style 7--11 mm, densely villous. Achenes obovate to elliptic, 3--4.5 × 2--2.8 mm, glabrous; persistent style 2.5--3.2 cm, plumose. Fl. Jun--Aug, fr. Aug--Oct.

S Gansu, S Shaanxi, N to W Sichuan, E Xizang, NW Yunnan.

* Forests, forest margins, slopes; 1400--4000 m.

Clematis fargesii Franchet; C. fargesii var. souliei Franchet ex Finet & Gagnepain; C. montana Buchanan-Hamilton ex de Candolle var. potaninii (Maximowicz) Finet & Gagnepain; C. potaninii var. fargesii (Franchet) Handel-Mazzetti.

Clematis potaninii, the old man's beard, is a species of flowering plant in the family Ranunculaceae, native to Tibet and central China. A deciduous woody vine, in the wild it is found climbing on slopes and in forests, particularly forest edges, at elevations from 1,400 to 4,000 m (4,600 to 13,100 ft). Its cultivar 'Summer Snow', also known as 'Paul Farges', has gained the Royal Horticultural Society's Award of Garden Merit.

Seedhead

Clematis potaninii là một loài thực vật có hoa trong họ Mao lương. Loài này được Maxim. mô tả khoa học đầu tiên năm 1890.

美花铁线莲（学名：Clematis potaninii）为毛茛科铁线莲属下的一个种。