A deciduous, small tree, with distinctly three-lobed leaves 11⁄2 to 31⁄2 in. long, and about the same from tip to tip of the side lobes, which point forward, and are triangular and pointed; the leaf is distinctly three-nerved, and tapers to the rounded base; margins irregularly, sometimes obscurely, toothed; upper surface bright dark green, lower one dull and slightly glaucous. Except for a loose floss on the lower surface when quite young, which soon falls away, the leaf is glabrous; leaf-stalk slender, as long or longer than the blade. Flowers in a downy, umbel-like corymb, numerous, small. Fruit with keys 3⁄4 to 1 in. long; the wings 1⁄4 in. wide, parallel or connivent.
Native of China; originally described as A. trifidum from a specimen collected there in the eighteenth century. It is probably not a genuine native of Japan, but the present name is based on a tree cultivated in that country. It was introduced to Kew in 1896, where it thrives very well and grows quickly; the largest tree now in the collection is 36 × 3 ft (1967). It is rather uncommon in gardens but worthy of wider cultivation, for it is very distinct in its rich-green, rather ivy-like leaves, which are held long into the autumn without any change of colour. The leaves on wild trees are, however, rather variable in shape; some are entire or only faintly lobed, and such leaves appear to be the rule in the Formosan variety (var. formosanum (Hayata) Sasaki). In the polymorphism of its leaves A. buergerianum recalls A. paxii, but in that species they are evergreen. The degree to which this character is shown by cultivated trees seems to depend on the age of the specimen and even, perhaps, on the season.
var. trinerve (Dipp.) Rehd. A. trinerve Dipp. – Lateral lobes spreading, produced near the base of the leaf, margins of all three lobes coarsely toothed, underside of leaves glaucous. This is thought to be a juvenile form of the species and was introduced from Japan in the nineteenth century. According to Pax it was grown on the continent as a greenhouse plant under the name “A. trifidum”. In shape, the leaves resemble those of A. pilosum and A. pentapotamicum.
From the Supplement (Vol. V)
It is far from being invariably true that the leaves of this species fall without changing colour. In the Mallet Court collection they turn red, orange or sometimes purple. Mr Harris remarks that it makes a good bonsai tree.
specimens: Kew, 46 × 31⁄4 ft (1979); National Pinetum, Bedgebury, Kent, pl. 1934, 36 × 3 ft (1983); Cowdray Park, Sussex, 34 × 41⁄4 ft at 3 ft (1982); Norham Road, Oxford, 50 × 53⁄4 ft (1981).
† cv. 'Maruba Tokaede'. – Leaves of firm texture, with short, blunt lobes, some quite unlobed. There is an example in the Hillier Arboretum.