also called  Brown Oak  (Quercus robur), ornamental and timber tree of the beech family (Fagaceae) that is native to Eurasia but also cultivated in North America and Australia. The tree has a short, stout trunk with wide-spreading branches and may grow to a height of 25 m (82.5 feet). The short-stalked leaves, 13 cm (5 inches) or more long, have three to seven pairs of rounded lobes; they are dark green above and pale green beneath and retain their colour into winter. Many varieties are cultivated as ornamentals, including a popular columnar form. The tree's heavy heartwood was once extensively used in Great Britain for shipbuilding and carving.