Plenter forest
A plenter forest is a high forest managed in plenter operation . It is a steadily rejuvenating permanent forest , in which trees of all dimensions are mixed up from small to single trunks. In the plenter operation, individual trees are felled, creating a permanent high forest. Despite the supposedly primeval forest-like character, the Plenterwald is a managed forest .
history
It is unclear whether the expression plenter comes from plunder (worthless stuff) or from the Latin root word plenere (= to fill up, to make from it ). In the forestry history of the forest in Central Europe , clear cuts , the prerequisites for an age-class forest (such as: clearing activities in the Middle Ages, exports in the age of seafaring of colonialism , raw material requirements of industrialization ), as well as forms of permanent use with the removal of the wood that was just needed, were common .
The term to plenus would refer to the full supply of timber, of rods for tool handles, weapons and other equipment over timber to feed for the Waldhut , the economy of the small forest and the settlement nearby forest needs.
The name of the term to plunder is probably based on common mark ( common land ) shared farm forest. Such forests were used in an unregulated manner, as anyone could fell trees that were ready for harvest. With increasing intensity of use, e.g. B. During the wood shortage of the Middle Ages and the modern era, this overuse led to plunder forest - a term that was used synonymously with plenter forest . Until the 19th century, plenter forests, unless they were private forests, were mostly not used in a regulated manner. From 1827 to the end of the 19th century, plentering was therefore forbidden in large parts of France and Germany. In the Alpine region, on the other hand, clear-cutting was stopped again during this time, but the rebuilding of the forest still led to age-class forests.
Today's commercial forests, which with the exception of remnants and unprofitable extreme locations make up the total stock of Central European forests, are largely a product of reforestation in the 19th and 20th centuries, and in Germany also after clear cuts in the 1930s and after the Second World War.
Management
Plenter forest stands that are modeled on natural forest regeneration are possible in mixed forests as well as in pure-variety forests.
Plentering in the strict sense of the word is the management of semi-shade and shade trees, usually beech and silver fir . Due to their special shade tolerance and growth dynamics, it is possible for them to remain in the shelter for decades and to grow into a dominant tree after being released. Plenter forests in spruce cultures and similar dense trees are more complex, the stock must then be kept more loosely than is usual with trees of the same age group, which are usually about the same height. This type of farming is particularly critical with spruce, because it leads to knotty wood, and the over-covered spruce stock also helps the poles to grow well. It is possible, for example, in the alpine mountain forest, which is of course much looser - for example, as a standard care method in the protective forest (Bannwald). However, mixed forests are best suited .
The sustainability of the wood use of a forest enterprise is achieved in the plenter forest through the even regrowth of trees even on a small plot. Correct plentering requires the professional evaluation of each individual tree from a certain age. In contrast, the demographic sustainability of age category forests is only guaranteed over larger areas if plots with trees of every age group grow back.
The sustainability of the plenter forest is measured by the ratio of the number of trunks to the diameter distribution, on the plenter or equilibrium curve . It is approximately an exponentially decreasing curve from a high number of thin trees to a small number of thick trees. Establishing such a balance from a single-layer stand requires, wherever possible, targeted forestry activity over several generations.
Spread and claims
Plenter operation is therefore most likely where the ecological requirements of red beech ( mixed deciduous forests ) and those of silver fir (beech-fir forests or beech-fir (spruce)) overlap, or where the common beech is already limited. Geographically, this corresponds to the area from Thuringia in the north to the south in the Alpine foothills, as well as from the Vosges in the west to far east. According to Ellenberg (1996), within this area, more or less red beech or spruce- rich ( Fagion ) beech-silver fir forests or silver fir-spruce forests would thrive in the following locations:
- planar to montane soils rich in bases in the subcontinental climate,
- on clayey (base-rich) soils rich in precipitation in montane to subalpine areas, or
- on waterlogged soils in submontane and montan climates with high levels of precipitation.
In Germany, plenter forests occur in peasant forests in the Black Forest , in the Allgäu and in the Bavarian Forest . In the area of the north-west Thuringian edge plates, these are v. a. the Hainich and Dün mountain ranges , one finds the special form of pure beech woodland. In Switzerland selection forests are widespread. Especially in the Neuchâtel Jura and the Emmental, spruce, silver fir and some beech are used for planking. In addition, there is also planning in the French Jura, Austria and Slovenia .
ecology
It is difficult to distinguish between natural fir forests and mixed forests rich in beech, in which the silver fir (Abies alba) was favored by plentering: Plenter operations favor the fir over the common beech (Fagus sylvatica) where their distribution areas overlap . The differences to the plenter phase of a primeval forest ( mosaic cycle concept ) are not always recognizable at first glance. However, plenter phases are rather rare in the still existing East Central European primeval forests. Nor can it be assessed whether the plenter forest generally corresponds to the potentially natural (pnV) forest community of the location. Spruce woodland forests that are no longer managed (e.g. in the Neuchâtel Jura) are similar in appearance to age group forests.
In principle, the plenter forest can be counted as a permanent forest in the general sense, as a forestry type of operation differs from permanent forest in the narrower sense. Even very minor interventions by plenter operations, i.e. the felling of selected individual trunks, can have a considerable influence on the species composition of the tree layer. The same applies to the age structure, the cycle time of the blows follows economic, not ecological guidelines.
These interventions create a clearly differentiated vertical structure. The undergrowth is vital and potentially corresponds to the plenter phase of a primeval forest, but only if the game population allows this (otherwise the silver fir, for example, disappears from the undergrowth due to selective browsing). Deadwood , however, is largely absent, as the trees are usually removed before their biological age death. In the horizontal structure, however, the plenter forest is poorer and more uniform than a primeval forest, as there are no areas with pronounced regeneration and decay phases.
The artificially maintained high forest condition contradicts the natural forest development to a greater or lesser extent, depending on the PNV. In areas that would naturally have pure coniferous forests ( spruce forest , fir forest ) as PNV, the age class forest would possibly correspond more to the natural development than the permanent high forest condition of the plenter forest. On the other hand, the fir-beech-plenter forest is a permanent state that is naturally most likely to be found in mixed deciduous forests that are rich in red beech.
In the forestry of the 18th and 19th centuries, which tried to counteract the progressive devastation of Central Europe with massive afforestation, more pure coniferous forests were planted on the eroded and impoverished soils. For example, the spruce can withstand the open space conditions (which e.g. does not apply to the silver fir and red beech) and makes few demands on the soil. The resulting forests were then operated as age-group forests. In most locations, however, these coniferous forests do not correspond to the PNV and are therefore classified as very remote from nature (of course, age-class forests are only in regular forest fire areas, in exposed locations due to rare extreme windthrow, or in border areas due to mass deaths in particularly unfavorable years, and similar situations). In some areas, such as bogs and waterways ( fringing forest and alluvial forest zone), monoculture forests have to be classified as harmful.
The much rarer plenter forests, on the other hand, have a clearly differentiated vertical structure. Plenter forests have distinct floors, as vegetation occurs at all heights. Since the 20th century, more and more forests have been converted, as a mixed forest as a permanent high forest is less prone to damage than, for example, a spruce forest. This also potentially promotes the biodiversity of flora and fauna. In the case of plenter operations, the species composition of the forest can be assessed as being relatively closer to nature in most cases, but not as natural.
See also
literature
- Heinz Ellenberg : Vegetation of Central Europe with the Alps. From an ecological, dynamic and historical perspective (= UTB for Science 8104 Big Series ). 5th, heavily changed and improved edition. Eugen Ulmer, Stuttgart 1996, ISBN 3-8252-8104-3 .
- Heinrich Reininger: The plenter principle or the transfer of the age group forest. Leopold Stocker Verlag, Graz u. a. 2000, ISBN 3-7020-0874-8 .
- Jean-Philippe Schütz: The plenter forest and other forms of structured and mixed forests. Parey Buchverlag, Berlin 2001, ISBN 3-8263-3347-0 (similar: dsslb .: Plentering and its different forms. Script for the lecture Silviculture II and Silviculture IV, October 2002 version; pdf, ethz.ch).
Web links
- Plenterwald, a sprout from peasant forest and silver fir. waldwissen.net
- Why plenter? waldwissen.net
- Plenter anywhere? waldwissen.net
- Farm forest: Plentering as the ideal form of cultivation. Bernhard Henning in: The Farmer (online, landwirt.com).
Individual evidence
- ↑ H. Ellenberg 1996, p. OA
- ↑ a b Pascal Junod, Peter Ammann (translation): To what extent do plenter forests and permanent forests differ? Waldbau (FWB) - Center de compétence en sylviculture (CCS), Lyss, February 9, 2012 (pdf, on waldbau-sylviculture.ch).