Timber harvest
The timber harvest is the removal of (standing) trees from a forest or a wood plantation in order to convert them into a salable or usable condition. The timber harvest begins with the felling of the tree and usually ends with the transport to a collection point ( pile area ), from which it can be transported away by truck.
Organizational workflow of the timber harvest
Essentially, the wood harvest can be divided into two organizationally and temporally separate work processes: the logging and the logging. However, with increasing mechanization of forest work, there are also possibilities to handle logging and bringing it in one operation using a so-called harwarder (= har (vester) + (for) warder ).
Logging
Logging, also known as logging - traditionally carried out by the lumberjack - includes the actual felling work and the subsequent processing of the felled tree. The spectrum of possibilities ranges from purely manual work with primitive tools to highly mechanized processes such as the wood harvester .
- Felling work: The separation of the tree trunk from the rootstock and the targeted placement at the felling site.
- Processing : The delimbing and de-trapping of the felled tree, as well as the division of the trunk into shorter parts to divide the assortments or to achieve transportability. In the case of raw wood , the quality class is usually determined and the processed trunk parts are measured, unless this is done in the receiving plant.
- Debarking: Coniferous wood was originally debarked manually, mostly at the felling site. Nowadays, debarking is almost always done by machine, either after the wood has been brought to the forest storage location or in the factory.
Bringing wood
Timber harvesting and felling are usually carried out separately in time - for reasons of avoiding danger and optimizing the work flow. However, close interlinking between the felling and harvesting of the wood may also be necessary, for example in tight spaces or on steep slopes.
Bringing the wood initially includes taking the reclaimed logs to a collection point, from which they can be taken to the customer by truck. The various wood assortments are then almost always bundled in an orderly manner to form wooden gander or piles of wood.
The following methods of bringing wood are possible:
- Wooden back with a forwarding vehicle: This is the most common method. It can be the case that smaller vehicles (or other methods) are used in sensitive or inaccessible parts of the forest and the final transport to the forest storage area is carried out separately. Examples of (timber) forwarding vehicles are: Forwarders , forest tractors and Elliators .
- Wooden back with back horse: This was once the common method. Nowadays this is only done in rare, particularly sensitive cases (e.g. in water protection areas ) or as a hobby.
- Manually carrying the wood to the forest storage area: Until the advent of hydraulic cranes and other mechanization, firewood, plywood, poles and the like were mostly carried or pulled out of the forest.
- Holzen: Another name is "drifting". In mountainous areas, the wood used to be "driven" on sufficiently steep slopes with the help of a sappie . Snow or rain made the work easier. A so-called giant could also be erected if the volume was sufficient . This was a veritable slide made of suitable tree trunks. The rest of the transport was then carried out either by back horse or by drifting . Manual driving over short distances is still carried out today, for example in connection with pulling ropes.
- Rope delivery: on slopes or other inaccessible areas, wood can be brought to an intermediate or final storage area with a temporarily constructed cable car .
- Helicopter delivery: This method is used as an alternative to rope delivery where the installation of a temporary cable car is uneconomical or not possible at all. This procedure is also called heli-logging .
Wood recording
The so-called “wood pick-up” is also part of the timber harvest. This is the recording of the quality class and dimensions that have generally already been determined in an electronic storage medium or on paper. This can be done in the course of processing or as a separate operation after the wood has been brought to the wood collection point. It is not uncommon for the forest owner or a forester to carry out the logging , as this also involves a certain control function.
Increasingly, however, the logging is being relocated to the receiving plant, since there the measurement and quality can be determined more cost-effectively using today's technology than in the forest. This also eliminates the so-called “wood takeover” in the forest, in which the price-determining wood characteristics are mutually recognized and the risk of loss and destruction is passed on from the forest owner to the wood buyer.
Timber harvest in Germany
For the Federal Republic of Germany, detailed data on the timber harvest by year are published in logging statistics. The following is an overview of the statistics for Germany:
- 54,356,200 cubic meters of total logging in Germany in 2014
- 55,612,700 solid cubic meters of total logging in Germany in 2015
- 52,193,500 solid cubic meters of total logging in Germany in 2016
- 53,490,700 solid cubic meters of total logging in Germany in 2017
- 64,361,900 solid cubic meters of total logging in Germany in 2018
Other timber harvesting methods
In energy wood plantations, the harvesting process is less based on the classic wood harvest. One possible method there is the use of appropriately adapted forage harvesters . The production of wood chips in the forest with the help of a wood chip harvester does not fit into the prevailing pattern of wood harvesting either .
See also
Web links
- Video harvesters and forwarders - what is it? on www.forstcast.net
Individual evidence
- ↑ Federal Statistical Office (Germany), technical series. 3, agriculture, forestry, fishing. 3, Agricultural land use and crop production. 3, forest land use. 1 Overview of the logging statistics ( Memento from April 29, 2019 in the Internet Archive )
- ↑ Federal Statistical Office (Germany), Logging Statistics Germany 2014 ( Memento from April 29, 2019 in the Internet Archive )
- ↑ Federal Statistical Office (Germany), Logging Statistics Germany 2015 ( Memento from April 29, 2019 in the Internet Archive )
- ↑ Federal Statistical Office (Germany), Logging Statistics Germany 2016 ( Memento from April 29, 2019 in the Internet Archive )
- ↑ Federal Statistical Office (Germany), Logging Statistics Germany 2017 ( Memento from April 29, 2019 in the Internet Archive )
- ↑ Federal Statistical Office (Germany), Logging Statistics Germany 2018 ( Memento from April 29, 2019 in the Internet Archive )