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Quercus robur (sometimes considered Q. pedunculata) is commonly known as the pedunculate oak or English oak.
It is native to most of Europe, and to Asia Minor to the Caucasus, and also to parts of North Africa.
Q. robur (Latin quercus, "oak" + robur "strength, hard timber") 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.
The populations in Italy, southeast Europe, and Asia Minor and the Caucasus are sometimes treated as separate
species, Q. brutia Tenore, Q. pedunculiflora K. Koch and Q. haas Kotschy respectively.
A close relative is the Sessile Oak (Q. petraea), which shares much of its range. Q. robur 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 × rosacea.
Description
Q. robur is a large deciduous tree 25–35 m tall (exceptionally to 50 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 the following autumn. 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 specimen of notable longevity is one in Stelmu˛e., Lithuania which is believed
to be approximately 1,500 years old, possibly making it the oldest oak in Europe; another specimen, called the
Kongeegen (Kings Oak), estimated to be about 1,200 years old, grows in Jaegerspris, Denmark. Yet another can be
found in Sweden, Kvilleken. It is over 1,000 years old and 14 meters around. Of maiden (not pollarded) specimens,
one of the oldest is the great oak of Ivenack, Germany. Tree-ring research of this tree and other oaks nearby gives
an estimated age of 700 to 800 years old.
Within its native range Q. robur 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. The wood of Q. 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. The earlywood
displays a vast number of large vessels (~0.5 mm diameter). Rays which resemble of thin (~0.1 mm) yellow or light
brown lines run across the growth rings.
Uses
Oak wood has a density of about 0.75 g/cm³, great strength and hardness, and is very resistant to insect and
fungal attack because of its high tannin content. It also has very attractive grain markings, particularly when
quarter-sawn. Wide, quarter-sawn boards of oak have been prized since the Middle Ages for use in interior paneling
of prestigious buildings such as the debating chamber of the British House of Commons in London, England, and
in the construction of fine furniture. Oak wood, from Quercus robur and Quercus petraea, was used in Europe
for the construction of ships, especially naval men of war, until the 19th century, and was the principal
timber used in the construction of European timber-framed buildings.
Today oakwood is still commonly used for furniture making and flooring, timber frame buildings, and for veneer
production. Barrels in which red wines, sherry, brandy and spirits such as Scotch whisky and Bourbon whiskey are
aged are made from European and American oak. The use of oak in wine can add many different dimensions to wine
based on the type and style of the oak. Oak barrels, which may be charred before use, contribute to the colour,
taste, and aroma, of the contents, imparting a desirable oaky vanillin flavour to these drinks. The great
dilemma for wine producers is to choose between French and American oakwoods. French oaks (Quercus robur,
Q. petraea) give the wine greater refinement and are chosen for best wines since they increase the price
compared to those aged in American oak wood. American oak contributes greater texture and resistance to
ageing, but produces more violent wine bouquets. Oak wood chips are used for smoking fish, meat, cheeses
and other foods.
Oak bark is also rich in tannin, and is used by tanners for tanning leather. Acorns are used for making
flour or roasted for acorn coffee. Oak galls were used for centuries as the main ingredient in manuscript
ink, harvested at a specific time of year.
Mythology
In Celtic mythology it is the tree of doors, believed to be a gateway between worlds, or a place where
portals could be erected.
In Norse mythology, the oak was sacred to the thunder god, Thor. Some scholars speculate that this
is because the oak, as the largest tree in northern Europe, was the one most often struck by lightning.
Thor's Oak was a sacred tree of the Germanic Chatti tribe. Its destruction marked the Christianisation
of the heathen tribes by the Franks.
In Classical mythology the oak was a symbol of Zeus and his sacred tree. An example is the oracle of
Dodona, which in prehistory consisted solely of a holy oak.
Thanks to wikipedia for the above text
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Oak Leaves and Acorns
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