A deciduous tree up to 60 ft high, but usually much smaller, with stout, very pale grey, glabrous young shoots; terminal winter-buds covered with red-brown down. Leaves pinnate, 7 to 15 in. long, composed of from five to thirteen leaflets. The lowest ones are usually rounded to ovate, about 1 in. long and 3⁄4 in. wide, the remainder gradually increasing in size and changing in shape to oval and obovate towards the terminal one, which is the largest and from 3 to 51⁄2 in. long by 11⁄4 to 21⁄2 in. wide; they are pointed and distinctly toothed, the upper surface slightly downy when the leaf is young, the lower one having tufts of down in the vein-axils. Flowers pure white, produced in terminal, erect, much- branched, downy panicles 6 to 12 in. high and wide; each flower is 1⁄6 to 1⁄4 in. wide.
Native of Korea, where it was discovered in 1863 by Richard Oldham, the Kew collector, and of China, whence it was introduced by Wilson in 1900. It is extremely rare in cultivation, but a tree about 15 ft high at Kew grows freely except when cut by late spring frost. Wilson describes it as a fine tree occurring in the moist woods and thickets of W. Hupeh, but not really common there. It appears to be related to M. beaniana, but differs in the terminal inflorescence and in flowering later when the leaves are nearly fully grown. The tree at Kew flowered in July 1942. There is an example measuring 35 × 21⁄2 ft at Talbot Manor, Norfolk (1970). The example at Kew, raised from seeds received from the Lushan Botanic Garden in 1935, measures 27 × 2 ft (1970). It flowers fairly regularly.