Red Oak

Red Oak (Quercus rubra) is a tree of the Fagaceae family, native to the North American region, i.e.the eastern states of the USA and Canada around the Great Lakes. Cultivated for forestry use due to its rapid growth and for ornamental purpose due to the beauty of its foliage, red in autumn, has become sometimes invasive in Quercus Robur woods of central-northern Europe and northern Italy, especially in Lombardy, Piedmont and Veneto, where its planting and cultivation are prohibited to protect local biodiversity. Its leaves are deciduous, composed and alternated. It is a monoecious plant, in which male flowers are assembled in 10-15 cm long pendulous catkins, with many stamens, which appear on the previous year branches before the leaves appear. Its female unisex flowers open from mixed gems after the male ones (proterandria), are single or assembled in groups of 2-3, rarely 4, and appear on the new shoots, at the same time as the leaves. The fruit is a drupe, composed of the fleshy, fibrous, exocarp (husk) blackening at maturity and releasing the woody endocarp, i.e. the real walnut, consisting of two half shells that enclose the kernel with high lipid content