Deciduous tree. Leaves 3-8 cm across, 5-lobed; lobes sometimes lobulate, obtuse or rounded, rarely acute; lobules obtuse, sinuses acute; base subcordate. Inflorescence corymbose. Samaras horizontal, often sigmoid along the back.
It is a deciduous tree reaching 15–25 metres (49–82 ft) tall, with a trunk up to 1 metre (3 ft 3 in) in diameter, with finely fissured, often somewhat corkybark. The shoots are brown, with dark brown winter buds. The leaves are in opposite pairs, 5–16 centimetres (2.0–6.3 in) long (including the 3–9 centimetres (1.2–3.5 in) petiole) and 5–10 centimetres (2.0–3.9 in) broad, with five blunt, rounded lobes with a smooth margin. Usually monoecious, the flowers are produced in spring at the same time as the leaves open, yellow-green, in erect clusters 4–6 centimetres (1.6–2.4 in) across, and are insect-pollinated. The fruit is a samara with two winged achenes aligned at 180°, each achene is 8–10 millimetres (0.31–0.39 in) wide, flat, with a 2 centimetres (0.79 in) wing.[6][7]
The two varieties, not accepted as distinct by all authorities, are:[4][6]
The closely related Acer miyabei replaces it in eastern Asia.[6]
Field maple is an intermediate species in the ecological succession of disturbed areas; it typically is not among the first trees to colonise a freshly disturbed area, but instead seeds in under the existing vegetation. It is very shade-tolerant during the initial stages of its life, but it has higher light requirements during its seed-bearing years. It exhibits rapid growth initially, but is eventually overtaken and replaced by other trees as the forest matures. It is most commonly found on neutral to alkaline soils, but more rarely on acidic soil.[9]
Diseases include a leaf spot fungus Didymosporina aceris, a mildewUncinula bicornis, a cankerNectria galligena, and verticillium wiltVerticillium alboatrum. The leaves are also sometimes damaged by gall mites in the genus Aceria, and the aphidPeriphyllus villosus.[13]
The field maple is widely grown as an ornamental tree in parks and large gardens. The wood is white, hard and strong, and used for furniture, flooring, wood turning and musical instruments,[14] though the small size of the tree and its relatively slow growth make it an unimportant wood.[6]
It is locally naturalised in parts of the United States[10] and more rarely in New Zealand.[15] The hybrid maple Acer × zoeschense has A. campestre as one of its parents.[7]
The tree has gained the Royal Horticultural Society's Award of Garden Merit.[16]
Over 30 cultivars of Acer campestre are known, selected for their foliage or habit, or occasionally both; several have been lost to cultivation.[17]