A deciduous tree to 40 ft high in cultivation, with a dark brown, peeling bark; young stems covered with a glaucous bloom. Leaves 4 to 5 in. long and slightly more wide, usually with three lobes, the central one broadly triangular, the lateral ones shorter, all tapered at the apex; sometimes five-lobed by the addition of two small lobes near the base; glabrous above, downy at first and prominently net-veined beneath; margins rather coarsely and remotely toothed. Flowers in corymbs. Wings of fruit almost parallel; keys to 2 in. long, with convex nutlets.
Native of China; discovered by the missionary Giraldi in Shensi; introduced by Forrest from Yunnan. It is rare in gardens but there is an example at Caerhays Castle, Cornwall, measuring 39 × 3 ft; others grow at Dawyck, Peebl., Hergest Croft, Heref., and at Birr Castle and Headfort, Eire.
A. caesium Wall. – This is the Himalayan counterpart of A. giraldii. Leaves usually five-lobed, the lobes more tapered at the apex; margins more finely toothed; undersides not so prominently net-veined.
From the Supplement (Vol. V)
specimens: Caerhays, Cornwall, 48 × 31⁄2 ft (1984); Dawyck, Peebl., 20 × 13⁄4 ft (1982).
A. caesium – The author of this species should be given as Wall. ex Brandis, since Wallich's A. caesium was a bare name until Brandis provided a description.
It is in cultivation at Wakehurst Place, Sussex, from seeds collected in Kashmir, which is its western limit (Lancaster 144). Eastward it ranges as far as Nepal.