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Links to Dendrology Genus Directory of Images:

Genera : 2

Species: 102 - 153

Distribution: Northern Hemisphere deciduous forest.

Economic Uses: As timber, landscape ornamentals and for maple sugar and syrup.

Defining Features of Interest: The majority of species are in the genus Acer, with the remaining two species in the genus Dipteronia and confined to China. Winter sap contains a high concentration of stored sugars.

Fossil Evidence: Fossil plant parts are common in the Eocene.

Defining Morphology

Floral Features : Actinomorphic and perfect or unisexual ( dioecious, monoecious or polygamous). Flowers are small and in inflorescences of corymbs, panicles, racemes, or umbels. Hypogynous or perigynous.

Fruit and Seed Features : Fruit a winged schizocarp or samara. Seed is solitary and without endosperm. Placentation is axile.

Vegetative Features : Habit is as shrubs or trees. Leaves simple (rarely palmately or pinnately compound) and with palmate veins. Opposite and deciduous or evergreen. Stipules lacking.