Spruce

Other name:      red-spruce

Botanic Name:  Picea abies

German:            Fichte

Culture history

The modest but productive spruce saved forestry which had to wake up after decades of overfelling thanks to its advantages concerning the reforestation of bleak landscapes. The widespread type of tree provides nearly everything from building timber to christmas trees. No other tree offers a similar range of use from strong pallets to formwork in concrete building and elegant timber structure. All this is crowned by the

exclusive sound wood which is manufactured to soundboards of pianos and string instruments.

In general

About 60 percent of the Austrian commercial timberland is made up by spruces which makes it the most important domestic tree. Sometimes this dominance leads to ignore the numerous qualities of the spruce. Its trunks are cylindric and very straight but they tend to spiral growth. Spruces can be up to 600 years old but they are mostly felled between 80 and 120 years. Often the monoculture of the spuce was criticized but this is not true anymore concerning Austrian forestry.

Characteristics of the timber

The edges of the annual rings are clearly marked by the closing dark late wood and the new light early wood. This gives a decorative character to the wood. The annual rings may vary according to the location of the tree, its age and cultivation but the part of late wood reaches not more than ¼ of the annual ring. It is possible that these rings are only 1 mm wide if the tree is very old and situated in higher regions. Some spruces offer a fine-wavy fibre course which is called “Hazel-Spruce”. Freshly sliced timber is nearly white and matta s there is a larger part of early-wood. Late-wood is yellowish to reddish-brown. Its nearly white basic colour tends to turn yellow in the sunlight, later on the colour becomes honey-brown-yellow.

Properties

Spruce is light (kiln density 410 kg/m³) and soft (Brinell hardness 12 N/mm²). Spruce timber adjust quite slowly to the climate of the surrounding concerning the moisture. Spruce is easy to work, to bark and to cut if there are only few knots inside. There are no problems concerning seasoning buti f the wood is dried very quickly there may come tiny shakes. The treating of the surface is easy without any problems. Spruces are found in class 4 concerning durability and they are vulnerable to bark anobiids and house longhorns. The treatability of dry spruce wood is quite bad. If the wood is stored in water for a long time and if it is infected with bacteria there may come stains into the wood because of different absorption of liquids.

Verwendung

The spruce offers a huge variety of possible uses. It is the most important construction timber, it can be used as solid wood or lamellae. In addition ist is used for carpenter works, indoors, semi-finished-goods, constuctions, formworks, windows, doors, packaging, furniture and instruments. Spruce wood is the main component of cellulose production and it provides a big part of industrial timber and woodchips for wooden panels. So it is also used for energy because saw dust and wood shavings are sold as briquettes and pellets.

Quelle: www.proholz.at