A deciduous tree of dense, rounded habit, occasionally more than 50 ft (usually 20 to 30 ft) high, sometimes scarcely more than a shrub; branchlets glabrous. Leaves three-lobed, with a heart-shaped base; 11⁄2 to 21⁄2 in. wide, less in length; dark green and glossy above, paler below, soon quite glabrous on both surfaces, except for a tuft of down where the three prominent veins join the stalk, which is 1 to 2 in. long and has no milky sap. Flowers greenish yellow, borne on drooping slender stalks 3⁄4 to over 1 in. long, in few-flowered corymbs or loose racemes. Fruit reddish, often very abundant, with wings 3⁄4 to 1 in. long, 1⁄4 to 1⁄2 in. wide, and pointing downwards, so that the inner edges nearly meet or even overlap.
Native of S. Europe and parts of Central Europe; also of N. Africa and the Near East; introduced, according to Aiton, in 1739. In general appearance this maple bears much resemblance to our native A. campestre, but is easily distinguished by its glabrous three-lobed leaves, without milky juice in the stalks. It is a small tree of neat and pleasing appearance, very suitable as an isolated specimen in a small garden. There are several fine examples in or near London, where this maple thrives well. The largest at Kew measures 45 × 5 ft (1965). Others are: West Ham Park, 46 × 61⁄4 ft (1956), and Kensington Gardens, 50 × 51⁄4 ft (1967). This maple is used as a hedge plant in the south of Europe.
From the Supplement (Vol. V)
specimens: Kew, by Lion Gate, 40 × 5 ft (1976) and, by Aroid House, 41 × 7 ft (1981); Kensington Gardens, London, 44 × 6 ft (1978); Oxford Botanic Garden, pl. 1900, 35 × 6[3/4] ft (1981); University Botanic Garden, Cambridge, 42 × 5[1/2] ft (1984); St Briavels, Glos., 42 × 7[1/4] ft (1976); Singleton Abbey, W. Glam., 48 × 6[1/2] ft (1982).
In its typical state A. monspessulanum is mainly, as indicated, a native of southern and parts of central Europe, and of North Africa; it also extends into western Anatolia. However, in most of Anatolia, the Caucasus, the Near East and southern central Asia its place is taken by related species, which have been included under it as subspecies. For these, see Flora of Turkey, Vol.2, pp. 516, 518 (1967). They differ from typical A. monspessulanum in technical characters of the flower rather than in foliage, which is variable in European trees.
There is in cultivation a small-leaved variant of A. monspessulanum, introduced from Corsica by the late Collingwood Ingram a few years before 1932. This has been confused with A. monspessulanum var. microphyllum Boiss. (A. m. subsp. microphyllum (Boiss.) Bornm.), which differs from the European trees primarily in floral characters, though its leaves are indeed rather small. It is a native of the Near East.
In addition to the subspecies occurring in Asiatic Turkey, there is A. turcomanicum Poyark. (A. monspessulanum subsp. turcomanicum (Poyark.) E. Murray), from the mountains south-east of the Caspian. This is described as having the leaves rusty-downy beneath even when mature.