Oak

Other commercial names common oak, holm oak, Turkey oak, red oak
Botanical name Quercus robur L.; Q. petraea (Matt.) Liebl.; Q. cerris L.;Q. rubra L.

Historical and cultural information
Up to today the value of oak forests has been measured according to their capacity to fatten pigs. Still today, connoisseurs appreciate ham from Spain and France coming from pigs fed on acorns. Excessive ship building during the XVIII century threatened oak forests, but fortunately at that same time repopulation occurred leading to the trees that are now mature to be felled. Oak does not yield quick income. If you plant an oak, you are thinking of the future. This is why oak represents continuity and strength. This plant is strongly anchored to the ground and it splits rather than becoming uprooted.

General information
Among the various types of oak (oak, common oak and Turkey oak), common oak is the one with the best shaped trunk, with branches generally dividing higher up compared to the knotty oak. Compared with the total wood mass in forests, these two species represent a mere 2%. The Turkey oak, instead, originates from southern Europe. Oaks can reach the age of 2000 years. Isolated oak trees usually have a knotty shape. Peat bog oak is not a real botanical species, but a name given to oak trunks that have been buried in bogs for centuries.

Characteristics
All oaks have a typical ring porosity with large and characteristic medullary rays. Local species, except for the Turkey oak, are classified as “white oak” and differ in colour from the “red oak”, which is slightly more reddish, and in the array and size of the vessels in late wood. The weak appearance of tylosis (obstruction of pores caused by particular tissues) in red oak is not a distinctive characteristic. The original light brown colouring of oak wood often becomes darker after drying . Obtaining an evenly clear wood is the aim of every drying specialist.

Properties
Oak wood is relatively heavy (dry density 670 kg/m3) and hard (Brinell hardness 34 N/mm2). Timbers of particular origin, such as Slavonia, French, Polish or Weinviertel oaks are often associated with particular characteristics. Oak wood can be easily sawed, planed, perforated and shaped. When working on this wood, it is advisable to ensure adequate suction of the powder which, in some people, can cause allergic reactions. Drying requires a lot of time and experience. Typical problems are cracks, deformation to the extent of cellular collapse and dark colouring. If, when damp, the wood comes into contact with metal, dark blue to black stains can appear due to the contents of tannic acid. With reference to the tannic acid contents, difficulties do not occur during usual treatment processes of the surface; the pores must be filled before varnishing. The heartwood is resistant against fungi (resistance class 2).

Use
Oak is one of the finest woods for making furniture, interiors, joinery, stairs, railings and panelling especially for the outdoors, and is suitable for other particular uses in outdoor and underground construction. Although often subject to the trend of the moment, oak wood remains first choice for solid furniture. A considerable amount of oak is devoted to parquet production. Traditionally it is used for facades and barrique barrels.