Branch

from Wikipedia, the free encyclopedia

A branch is the herbaceous or woody axis of a side shoot of the plants with corm (outdated: cormophytes). A branch can arise laterally from the axis of the basic shoot ( stem or trunk ) or from other branches. A branch is a branch with leaves. Colloquially, the term is often reduced to the woody branches of trees . In the use of wood , the distinction between branch and branch is common - or the branch is called, like the traces that the branch leaves in the wood, branch wood or "branch".

A tree struck by lightning opens the view inwards.

The branch on the tree: living branch and branch stump

Branch tied up with a loose knot

Living branches are at the top of the tree, the crown . Below is the trunk with its dead branch zone and the stumps of branches . Deviating from this, branches in the upper crown area also die when the braids are dry or branches develop on the trunk from water veins (sticky branches ).

If a branch breaks off the trunk, the tree tries to cover this wound. Depending on the shape, one speaks of bumps , knots ('knots', compare clubs and billets ), ribbons , roses , beards or seals . These almost always reduce the quality of the wood .

Branch thicknesses

The forestry distinguishes the following Aststärken :

  • Feinast : diameter is less than three centimeters
  • Weak branch : diameter is between three and five centimeters
  • Coarse : diameter is between five and ten centimeters
  • Starkast : diameter is over ten centimeters

This is known as standing timber from 7 cm in diameter and non-merchantable wood to 7 cm in diameter, including the fall brushwood for fine and weak branches. The top of the tree as a whole is summarized under the term plait wood, whether it is a trunk extension in softwood or branched branch wood .

The branch in the wood

Heavily branched tree

The material timber designated road as a growth feature, the heartwood of a branch, which up to the marrow results in the tree, and therefore, remains in all zones of the cut wood.

Depending on the location and arrangement of branches lead mostly to a reduction in the quality of wood as it will make grain disturbing and so the physical capacity decrease of the wood.

Branch purity and knotiness

Knot purity is generally a quality indicator for construction timber . The corresponding piece of wood is free ( pure ) of knots, but especially knotholes, and is used, for example, for construction timber , furniture , doors or windows . Wood with many branches is called knotty or way branching , which is a wood defects . Carpenter wood or veneer , especially with interesting grained types of wood without a tendency to knots , are an exception: For example, the stone pine with the typical black knots or the bird's eye maple is a popular wood.

  • In order to achieve branch purity, the trees are planted very closely ( in association ). They grow up quickly ( shoot up ) and form a short piece of plait and hardly any branches on the central trunk. Such wood is of the highest quality and is used as peeling wood for the production of veneers or in instrument making.
  • In the case of particularly beautiful straight conifers , the lower, mostly dry branches are removed. In the wood that after this so-called Pruning accrues on the trunk, the Äststümpfe be quickly and überwallt clean and are strong timber not on the surface.

Deciduous trees usually lose their branches by themselves, so that no value branches take place there. Oak is an exception, the dead branches of which remain on the tree for many years, and which plays an important role regionally as construction timber.

To avoid holes in a board, diarrheal branches are usually drilled out during manufacture and replaced with a knothole dowel .

Astrein became a word in youth language with a positive connotation.

Loose branches, knotholes

A knothole is created when a branch in a board becomes detached from the rest of the wood tissue and falls out, a failure branch .

Reasons for detachment from the remaining wood are:

  • Branch wood contains much more lignin . This makes it harder, more brittle and shrinks more when it dries.
  • The fibers do not run parallel to the fibers in the trunk.

Whether a branch fails depends on the one hand on the type of wood (the fir tree tends to do so more than the spruce , but the pine hardly), and on the other hand whether the branch stump was quickly overgrown or the dead wood remained on the trunk for a long time.

See also

Web links

Wiktionary: Ast  - explanations of meanings, word origins, synonyms, translations
Commons : Branch  - collection of images, videos and audio files

Individual evidence

  1. ^ Manfred A. Fischer, Karl Oswald, Wolfgang Adler: Excursion flora for Austria, Liechtenstein and South Tyrol . 3rd, improved edition. State of Upper Austria, Biology Center of the Upper Austrian State Museums, Linz 2008, ISBN 978-3-85474-187-9 .
  2. straight in the dictionary.
  3. ^ Ulrich Ammon: Variant Dictionary of German. De Gruyter, 2004, ISBN 978-3-11-016575-3 , p. 56, limited preview in the Google book search.