The Pedunculate Oak or Quercus robur (from Latin quercus, "oak" + robur "strength, hard timber") is native to most of Europe, and to Asia Minor to the Caucasus, and also to parts of North Africa.
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 section Quercus. It is a large deciduous tree 25 – 35m tall (exceptionally to 40 m), with lobed and nearly sessile (very short-stalked) leaves 7 – 14cm 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 is 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 – 8mm long, and by its pendunculate acorns. The two often hybridise in the wild, the hybrid being known as Quercus × 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.
It is planted for forestry, and produces a long lasting and durable heartwood, much in demand for interior and furniture work. The wood of Quercus robur is easily identified just by taking a closer look at the cross-section perpendicular to fibres. The wood is characterised by its distinct (often wide) dark and light brown growth rings.