Northern red oak (Quercus rubra L.) is a North American forest species cultivated in Europe since 1691 and found nowadays all over the Europe except from the Scandinavian countries. In Romania it is cultivated since the beginning of the 20-th century. At present pure and mixed northern red oak plantations cover over 2,500 ha and the majority of them are located between the pedunculate oak zone and the lower limit of European beech zone (up to about 700 m asl elevation), where it performs reasonably well on both fertile and deep soils as well as heavy clays. The paper deals with the biometrical performances of a northern red oak-dominated plantation established back in 1997 and located at a mean elevation of 780 m asl. At 10 years of age, northern red oak, even grown only under medium favourable ecological conditions (quite harsh climate and heavy soil), performs well, with an average height increment of 0.67-0.80 m/yr, an average diameter increment of 0.50-0.63 cm/yr and a mean volume increment of 4.75-6.14 cu.m/ha/yr. In the last three years (2008-2010), the individual northern red oak trees within the experimental plots have also performed well, with a mean diameter increment of 0.50-0.57 cm/yr. This value is higher (on average 0.81 cm/yr, with a variation between 0.53 cm/yr and 1.20 cm/yr) in case of the 100 potential final crop trees of northern red oak selected back in 2008.
