Hardwood

As a hardwood, the wood of deciduous trees is called. Even deciduous trees per se, are sometimes referred to as hardwood or hardwood or deciduous shrubs.

A distinction is made between members of coniferous wood, the wood of conifers ( conifers), belonging to the gymnosperms ( gymnosperms ), and more hardwood, the wood of deciduous trees, all of the class of angiosperms ( Angiospermae). The reason for this differentiation is the one these different systematic mapping of tree species to different groups of seed plants. On the other hand, the two classes of wood species differ considerably in composition, structure and properties.

Composition and structure

The chemical composition of hardwood similar to that of softwood ( see table). The largest share makes cellulose with 42 - 51%, while hemicellulose 27-40 % and lignin 18 - make up 24%.

Hardwood shows in his anatomical structure of a wider range than the relatively uniform structured softwood. In contrast to softwood, where the tracheids fulfill a double function ( strengthening, water pipe ) in the hardwoods a functional separation has occurred. It can be found weiterlumige vessels for water and nutrient transport from the root to the crown, the tracheae. The mechanical strengthening function essentially take the wood fibers, which can be divided into libriform fibers and fiber-tracheids. In addition, can occur Gefäßtracheiden and tracheids commonly present as more cells in certain types of wood; these represent an intermediate stage of development of the tracheid at special water guide The storage is of nutrients takes place in the Längsparenchym or in the ray parenchyma. The figure gives an overview of the different cell types of hardwood.

Use and meaning

Hardwood, as coniferous wood, as a building material ( lumber, engineered wood, etc. ), furniture wood, raw material for paper production or as a source of energy (firewood, wood for energy ) are used. Softwoods such as spruce, however, planted preferred due to their rapid growth. In addition, they usually have a straighter growth and are therefore easy to process more easily and with less waste to timber.

2007 and 2008, the proportion of hardwoods in Germany 17.1% ( 13.1 million m3) or 22.7 % ( 12.6 million m3) of the total removal ( 76.7 and 55.4 million m3). The proportion of deciduous forests in the German forest area, however, is around 41%. The proportion of houses is 14.8 %, 9.6% oaks and other deciduous trees at 15.7%.