A deciduous tree up to 30 ft high, with a rounded head of branches; young shoots glabrous or minutely downy. Leaves from 10 to 16 in. long, composed of seven, nine, or eleven leaflets, which are oblong to oblong-lanceolate, obliquely rounded or broadly tapered at the base, tapered at the apex to a fine point, 21⁄2 to 5 in. long, 1 to 13⁄4 in. wide, margins entire or sparsely toothed, glabrous and dark green above, but with a tuft of hairs at the base of the midrib and on the short stalk. Flowers small, produced in June on terminal pyramidal downy panicles 3 to 7 in. high, the main and secondary flower-stalks as well as the sepals covered with brown down; the greenish-white petals are also downy outside, and about 1⁄8 in. long. Fruits rich red, downy, about the size of peppercorns, densely packed in drooping panicles.
Native of China in the provinces of Kansu, Shensi, Shansi, Honan, and Hupeh; discovered by Potanin in Kansu in 1885, three years later by Henry in Hupeh; introduced by Wilson in 1902 when collecting for Messrs Veitch. It makes a quite handsome small or medium-sized tree, sometimes many-stemmed, and usually colours red in the autumn. But it rarely flowers or fruits in this country.
Among the largest recorded specimens are: Kew, pl. 1908, 40 × 5 ft (1967); Wakehurst Place, Sussex, 58 × 71⁄2 ft at 3 ft (1964); Westonbirt, Glos., in Clay Island, 55 × 5 ft at 2 ft (1966).
R. potaninii received an Award of Merit in 1932, for its foliage and autumn colour. The young plant exhibited in 1909 under the name R. sinica, which received the same award, was probably R. potaninii.
R.punjabensis Brandis – R.potaninii is closely related to this species, which in its typical state is a native of the N.W. Himalaya as far east as Kumaon. R. punjabensis has more hairy stems and foliage, but otherwise the two species scarcely differ. Rehder recognises a variety of R. punjabensis in China – var. sinica (Diels) Rehd. & Wils., differing from the Himalayan type in having the upper part of the rachis slightly winged and in the usually fewer and more sessile leaflets. R. potaninii is supposed to differ from this variety in being more glabrous, in having the leaflets distinctly stalked and in its unwinged leaf-rachis. But the differences are not at all clear-cut, and certainly R. potaninii cannot be reliably distinguished from R. punjabensis var. sinica by the differences given by Rehder in the key on p. 542 of the present (second) edition of his Manual. It is possible that R. punjabensis var. sinica is in cultivation in Britain from Wilson 275, collected during the first expedition for the Arnold Arboretum but, if so, it is probably by this time grown as R. potaninii.