The Probert Encyclopaedia of Nature

OAK

The oak is a tree of the genus Quercus, family Fagaceae, family Cupuliferae. They have a three-celled ovary and bear a round nut called an acorn. The timber of the British oak - the Pedunculate Oak or Common Oak (Quercus robur) is very hard, though prone to twisting, and was formerly used for building warships.
Research Oak