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It is the type species of the genus (the species by which the oak genus Quercus is defined), and a member of the white oak section Quercus subgenus Quercus section Quercus. The populations in Italy, southeast Europe, and Asia Minor & the Caucasus are sometimes treated as separate species, Q. brutia Tenore, Q. pedunculiflora K. Koch and Q. haas Kotschy respectively.
It is a large deciduous tree 25–35 m tall (exceptionally to 40 m), with lobed and nearly sessile (very short-stalked) leaves 7–14 cm long. Flowering takes place in mid spring, and their fruit, called acorns, ripen by autumn of the same year. The acorns are 2–2.5 cm long, pedunculate (having a peduncle or acorn-stalk, 3–7 cm long) with one to four acorns on each peduncle.
It forms a long-lived tree, with a large widespreading head of rugged branches. While it may naturally live to an age of a few centuries, many of the oldest trees are pollarded or coppiced, both pruning techniques that extend the tree's potential lifespan, if not its health.
A close relative is the Sessile oak (Quercus petraea), which shares much of its range. Pedunculate Oak is distinguished from this species by its leaves having only a very short stalk 3–8 mm long, and by its pendunculate acorns. The two often hybridise in the wild, the hybrid being known as Quercus x rosacea.
Within its native range it is valued for its importance to insects and other wildlife. Numerous insects live on the leaves, buds, and in the acorns. The acorns form a valuable food resource for several small mammals and some birds, notably Eurasian Jays Garrulus glandarius.
It is planted for forestry, and produces a long-lasting and durable heartwood, much in demand for interior and furniture work.
A number of cultivars are grown in arboreta and in parks and gardens. The most common cultivated form probably is the cultivar Quercus robur 'Fastigiata', with a narrow and columnar crown. This is propagated from an upright tree that was found in central Europe. Several hybrids with other white oak species have also been produced in cultivation, including Turner's oak Q. x turnerii (Q. ilex x Q. robur), Heritage oak Q. x macdanielli (Q. macrocarpa x Q. robur) and Two worlds oak Q. x bimundorum (Q. alba x Q. robur), the latter two developed by nurseries in the United States.
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