This biome is characterized by relatively warm summers, cold winters and sufficient precipitation (75 to 250 cm per year) (Raven and Johnson, 1992). The non- growing season is due to temperature-induced drought during the cold winters.
Many of the same genera are common to all of the northern hemisphere expressions of this biome. These include; Oak, Maple, Beech, Chestnut, Hickory, Elm, Walnut, and Sweetgum. Different species of these genera occur on each continent.
World wide distribution of deciduous forests