An oak is a tree or shrub in the genus Quercus
Latin "oak tree") in the beech family, Fagaceae. There are about 500 extant oak species.
The common name "oak" also appears in the names of species in related genera, particularly in names
of unrelated species such as Lithocarpus (stone oak) and Grevillea robusta (silky oak) and Casuarinaceae (o-oak).
The genus Quercus is native to the Northern Hemisphere and includes deciduous and evergreen species ranging from cold temperate to tropical latitudes in the Americas, Asia,
Europe, and North Africa.
North America has the largest number of oak species, with about 160 species, 109 endemic in Mexico and about 90 in the United States.
The second largest area of oak diversity is China, with about 100 species
