Teak, (genus Tectona grandis),is a large deciduous tree of the family Verbenaceae, one of the most valuable timber species.The tree has a straight but often buttressed stem (i.e., thickened at the base), a spreading crown, and four-sided branchlets with large quadrangular pith. The leaves are opposite or sometimes whorled in young specimens, about 0.5 metre (1.5 feet) long and 23 cm (9 inches) wide. In shape they resemble those of the tobacco plant, but their substance is hard and the surface rough. The branches terminate in many small white flowers in large, erect, cross-branched panicles.