Hardwood
Hardwood is a solid and heavy wood due to its high fiber content and its narrow vascular structure . The term was originally of a customs nature and was used for wood with a kiln density above 0.55 g / cm 3 (for example beech , oak , ash ). Mostly due to slow growth, the wood is dense and hard and difficult to work with. Very heavy wood over 1 g / cm 3 is called ironwood .
However, the properties of the wood are not always uniform across the board for a variety. For example, in Central Europe the birch is considered to be relatively worthless, mechanically weak softwood . If, on the other hand, the same tree species grows in very unfavorable locations such as in Central Europe on a northern slope with little light in the moor or in northern Scandinavia , then the annual growth remains very low and the annual rings are close together. The wood then becomes harder and more resistant, so that birch wood is traded like hardwood in Finland.
The English term hardwood should not be translated as hardwood, but rather as hardwood ; this term describes the origin of the wood and only indirectly the wood properties, since hardwoods are usually harder than conifers , but there are also soft hardwoods such as willow or poplar .
The hardness or density of the wood is not directly related to its durability when attacked by fungi and pests. For example, beech, ash or maple are among the least durable indigenous woods. Some soft woods such as larch or Douglas fir are relatively durable. The mechanical resilience is usually high in hardwoods, such as B. show the use of letters made of beech wood and antique comb- teeth made of ash wood.
literature
- Murray W. Nabors, Renate Scheibe: Botany. Pearson Education, Munich 2007, ISBN 978-3-8273-7231-4 .
See also
Web links
- Explanation and table with types of wood sorted according to density on kaminholz-wissen.de.
- Solid wood hardwoods - softwoods (accessed on June 19, 2020)
- List of wood species (accessed June 19, 2020)
- Wood science (accessed June 19, 2020)
- Investigation of different properties of West African wood species under the aspect of their use for engineering structures (accessed on June 19, 2020)
Individual evidence
- ^ Stefan Döring: Pellets as an energy source. Springer, 2011, ISBN 978-3-642-01623-3 , p. 45.