Aceroideae

Aceroideae is a subfamily of the flowering plant family Sapindaceae that includes the maples. In traditional classifications maples formed their own family, Aceraceae, but modern systems such as APG treat Acer as part of Sapindaceae, with Aceroideae used for the maple lineage within the family.

The subfamily is dominated by the genus Acer, which contains roughly 120–150 species of deciduous trees and shrubs. Members generally have opposite leaves that are simple and often palmately lobed, though lobing and leaf shape vary. The flowers are small and inconspicuous, produced in panicles or clusters, followed by distinctive samaras (winged fruits) that are usually single-seeded and wind-dispersed.

Aceroideae species are native to temperate regions of the northern hemisphere, with centers of diversity in East Asia and North America. They grow in forests, woodlands, and urban environments and are adapted to a range of habitats from lowlands to mountains. Many species are cultivated as ornamentals for their foliage, form, and autumn color.

Economically, maples provide syrup from several North American species, most notably Acer saccharum, and maple wood is valued for furniture and veneers. The genus also yields a wide array of cultivars selected for horticultural use.