A deciduous tree 50 to 90 ft high in the wild; young branches dark, glabrous. Leaves, except on extension growths, borne singly below the apex of slow-growing and long-lived spurs, each year’s growth marked by the scar left by the fallen leaf. The leaves are ovate or heart-shaped, long-pointed, with five or seven prominent nerves radiating from the base, 3 to 41⁄2 in. long, 2 in. wide, the margins evenly set with blunt teeth. Inflorescence a pendulous, catkin-like spike springing from the end of a spur and bearing numerous very small yellowish flowers. See further in generic introduction.
A native of central and western China, upper Burma, S.E. Tibet and (var. himalense) of the Himalaya as far west as E. Nepal; discovered by Augustine Henry in Hupeh; described in 1889 and introduced by Wilson in 1901 when collecting for Messrs Veitch. Like its cousin Trochodendron aralioides, it is more than just a botanical curiosity, being handsome in foliage and a picture of great elegance and beauty when bearing its slender catkins around midsummer. It is much hardier and less demanding than was once supposed. The largest example grows at Caerhays in Cornwall and measures 40 ft in height, with several stems, the stoutest 41⁄4 ft in girth (1975). But the other sizeable specimens are well distributed: The High Beeches, Handcross, Sussex, 39 × 21⁄2 ft (1974); University Botanic Garden, Cambridge, 37 × 23⁄4 ft + 2 ft (1976); Edinburgh Botanic Garden, pl. 1905, 30 × 31⁄4 ft (1970).
var. himalense Hara & Kanai – It was believed until recently that T. sinense had its western limit in upper Burma. But in 1963 the Japanese botanical expedition to E. Nepal discovered there a tetracentron that differs from T. sinense only in the mostly rather larger, longer-tipped leaves, with finer tips, and the laxer fruiting catkins. It is possible that this variety extends into upper Burma and Yunnan (Hara in Fl. East. Himalaya (1966), pp. 85-6). The variety was again found in 1967 by the Japanese expedition to Bhutan and is also now known to occur in the Assam Himalaya.