Clearfell Logging
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Clearcutting, clearfelling or clearcut logging is a forestry/
logging Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidding, on-site processing, and loading of trees or logs onto trucks or skeleton cars. Logging is the beginning of a supply chain ...
practice in which most or all trees in an area are uniformly cut down. Along with
shelterwood Shelterwood cutting is the progression of forest cuttings leading to the establishment of a new generation of seedlings of a particular species or group of species without planting. This silvicultural system is normally implemented in forests t ...
and seed tree harvests, it is used by foresters to create certain types of forest ecosystems and to promote select species that require an abundance of sunlight or grow in large, even-age stands. Logging companies and forest-worker unions in some countries support the practice for scientific, safety and economic reasons, while detractors consider it a form of deforestation that destroys natural habitats and contributes to climate change. Clearcutting is the most common and economically profitable method of logging. However, it also may create detrimental side effects, such as the loss of topsoil, the costs of which are intensely debated by economic, environmental and other interests. In addition to the purpose of harvesting wood, clearcutting is used to create land for farming. Ultimately, the effects of clearcutting on the land will depend on how well or poorly the forest is managed, and whether it is converted to non-forest land uses after clearcuts. While deforestation of both temperate and tropical forests through clearcutting has received considerable media attention in recent years, the other large forests of the world, such as the taiga, also known as boreal forests, are also under threat of rapid development. In Russia, North America and Scandinavia, creating protected areas and granting long-term leases to tend and regenerate trees—thus maximizing future harvests—are among the means used to limit the harmful effects of clearcutting. Long-term studies of clearcut forests, such as studies of the Pasoh Rainforest in Malaysia, are also important in providing insights into the preservation of forest resources worldwide.


Types

Many variations of clearcutting exist; the most common professional practices are: *''Standard (uniform) clearcut'' – removal of every stem (whether commercially viable or not), so no canopy remains. *''Patch clearcut'' – removal of all the stems in a limited, predetermined area (patch). *''Strip clearcut'' – removal of all the stems in a row (strip), usually placed perpendicular to the prevailing winds in order to minimize the possibility of windthrow. *''Clearcutting-with-reserves'' – removal of the majority of standing stems, leaving a few reserved for other purposes (for example as snags for wildlife habitat), (often confused with the
seed tree Seed trees are trees left after reproduction cutting to provide seeds for natural regeneration in the seed-tree method. These trees serve as both the gene source for the new crop of regeneration and as a source of timber during future cuttings. B ...
method). *'' Slash-and-burn'' – the permanent conversion of tropical and subtropicals forests for agricultural purposes. This is most prevalent in tropical and subtropical forests where
population growth Population growth is the increase in the number of people in a population or dispersed group. Actual global human population growth amounts to around 83 million annually, or 1.1% per year. The global population has grown from 1 billion in 1800 to ...
creates land needs from smallholders in
developing Development or developing may refer to: Arts *Development hell, when a project is stuck in development *Filmmaking, development phase, including finance and budgeting *Development (music), the process thematic material is reshaped * Photograph ...
and least developed countries. Slash-and-burn entails the removal of all stems in a particular area. This can be a form of deforestation, when the land is converted to other uses. However, some indigenous forest peoples, for example the 19th century Forest Finns rotate over the land and it does return to forest and this would be sustainable. Slash and burn techniques are typically used by civilians in search of land for living and agricultural purposes. The forest is first clear cut, and the remaining material is burned. One of the driving forces behind this process is a result of overpopulation and subsequent sprawl. These methods also occur as a result of commercial farming. The lumber is sold for profit, and the land, cleared of all remaining brush and suitable for agricultural development, is sold to farmers. Clearcutting contrasts with selective cutting, such as high grading, in which only commercially valuable trees are harvested, leaving all others. This practice can reduce the genetic viability of the forest over time, resulting in poorer or less vigorous offspring in the stand. Clearcutting also differs from a coppicing system, by allowing revegetation by seedlings. Additionally, destructive forms of forest management are commonly referred to as 'clearcutting'.


Clearcutting regeneration, harvesting or system

Clearcutting can be differentiated into *''Clearcutting'' - clean felling by complete exploitation and removal of all the trees in one operation ... a harvesting method * ''Clearcutting method'' - a method for regenerating an even-aged community by removing all the mature trees * ''Clearcutting system'' - a silvicultural system incorporating the clearcutting method to remove (clear) the mature community over a considerable area at one time Confusion between these different uses of the term is common. Furthermore, as indicated above many variations mean technically correct usage may not be descriptive enough to know what is meant on that particular occasion. A clearcut is distinguished from selective logging where typically only a few trees per hectare are harvested in proportions dictated by management objectives. Clearcut logging is also distinct from wildland fire use, and from forest thinning. In these latter two it is common practice to leave trees that are considered undesirable, such as those that are too diseased, stunted or small to be marketable. Selective logging is usually practiced in areas with access to infrastructure.


Effects on the environment

Environmental groups criticize clear-cutting as destructive to water, soil, wildlife, and
atmosphere An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A s ...
, and recommend the use of
sustainable Specific definitions of sustainability are difficult to agree on and have varied in the literature and over time. The concept of sustainability can be used to guide decisions at the global, national, and individual levels (e.g. sustainable livin ...
alternatives. Clear-cutting has a very big impact on the water cycle. Trees hold water and topsoil. Clear-cutting in forests removes the trees which would otherwise have been transpiring large volumes of water and also physically damages the grasses,
moss Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hor ...
es,
lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.ferns populating the understorey. All this bio-mass normally retains water during rainfall. Removal or damage of the
biota Biota may refer to: * Biota (ecology), the plant and animal life of a region * Biota (plant), common name for a coniferous tree, ''Platycladus orientalis'' * Biota, Cinco Villas, a municipality in Aragon, Spain * Biota (band), a band from Color ...
reduces the local capacity to retain water, which can exacerbate flooding and lead to increased leaching of nutrients from the soil. The maximum nutrient loss occurs around year two, and returns to pre-clearcutting levels by year four.Martin, C. W., Pierce, R. S., Likens, G. E., & Bormann, F. H. (1986). Clearcutting affects stream chemistry in the White Mountains of New Hampshire. Broomall, PA: US Department of Agriculture, Forest Service, Northeastern Forest Experiment Station. Clear-cutting also prevents trees from shading riverbanks, which raises the temperature of riverbanks and rivers, contributing to the extinction of some fish and
amphibian Amphibians are tetrapod, four-limbed and ectothermic vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terres ...
species. Because the trees no longer hold down the soil, riverbanks increasingly erode as sediment into the water, creating excess nutrients which exacerbate the changes in the river and create problems miles away, in the sea. All of the extra sediment and nutrients that leach into the streams cause the acidity of the stream to increase, which can kill marine life if the increase is great enough. The nutrient content of the soil was found to return to five percent of pre-clearcutting levels after 64 years, which demonstrates how clearcutting affects the environment for many years. Clearcutting can destroy an area's ecological integrity in a number of ways, including: the destruction of buffer zones which reduce the severity of flooding by absorbing and holding water; the immediate removal of forest canopy, which destroys the habitat for many rainforest-dependent insects and bacteria; the removal of forest carbon sinks, leading to global warming through the increased human-induced and natural carbon dioxide build-up in the
atmosphere An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A s ...
; the elimination of fish and wildlife species due to
soil erosion Soil erosion is the denudation or wearing away of the upper layer of soil. It is a form of soil degradation. This natural process is caused by the dynamic activity of erosive agents, that is, water, ice (glaciers), snow, air (wind), plants, and ...
and habitat loss; the removal of underground worms, fungi and bacteria that condition soil and protect plants growing in it from disease; the loss of small-scale economic opportunities, such as fruit-picking, sap extraction, and rubber tapping; and the destruction of aesthetic values and recreational opportunities.


Negative impacts

Clearcutting can have major negative impacts, both for humans and local flora and fauna. A study from the University of Oregon found that in certain zones, areas that were clear cut had nearly three times the amount of erosion due to slides. When the roads required by the clearcutting were factored in, the increase in slide activity appeared to be about 5 times greater compared to nearby forested areas. The roads built for clearcutting interrupt normal surface drainage because the roads are not as permeable as the normal ground cover. The roads also change subsurface water movement due to the redistribution of soil and rock. Clearcutting may lead to increased stream flow during storms,
loss of habitat Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...
and species diversity, opportunities for invasive and weedy species, and negative impacts on scenery, specifically, a growth of contempt by those familiar with the area for the wooded, planet aftermaths, as well as a decrease in property values; diminished recreation, hunting, and fishing opportunities. Clearcutting decreases the occurrence of natural disturbances like forest fires and natural uprooting. Over time, this can deplete the local seed bank.Pykälä, J. (2004). Immediate increase in plant species richness after clear‐cutting of boreal herb‐rich forests. Applied vegetation science, 7(1), 29-34. In temperate and
boreal Boreal may refer to: Climatology and geography *Boreal (age), the first climatic phase of the Blytt-Sernander sequence of northern Europe, during the Holocene epoch *Boreal climate, a climate characterized by long winters and short, cool to mild ...
climates, clearcutting can have an effect on the depth of snow, which is usually greater in a clearcut area than in the forest, due to a lack of interception and evapotranspiration. This results in less soil frost, which in combination with higher levels of direct
sunlight Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth, sunlight is scattered and filtered through Earth's atmosphere, and is obvious as daylight when t ...
results in snowmelt occurring earlier in the spring and earlier peak runoff. The world's rain forests could completely vanish in a hundred years at the current rate of deforestation. Between June 2000 and June 2008 more than 150 000 square kilometers of rainforest were cleared in the
Brazilian Amazon Brazilian commonly refers to: * Something of, from or relating to Brazil * Brazilian Portuguese, the dialect of the Portuguese language used mostly in Brazil * Brazilians, the people (citizens) of Brazil, or of Brazilian descent Brazilian may also ...
. Huge areas of forest have already been lost. For example, only eight to fourteen percent of the
Atlantic Forest The Atlantic Forest ( pt, Mata Atlântica) is a South American forest that extends along the Atlantic coast of Brazil from Rio Grande do Norte state in the northeast to Rio Grande do Sul state in the south and inland as far as Paraguay and th ...
in South America now remains. While deforestation rates have slowed since 2004, forest loss is expected to continue for the foreseeable future. Farmers slash and burn large parcels of forest every year to create grazing and croplands, but the forest's nutrient-poor soil often renders the land ill-suited for agriculture, and within a year or two, the farmers move on.


Positive perspectives

Clearcutting can be practiced to encourage the growth and proliferation of tree species that require high light intensity. Generally, a harvest area wider than double the height of the adjacent trees will no longer be subject to the moderating influence of the woodland on the microclimate. The width of the harvest area can thus determine which species will come to dominate. Those with high tolerance to extremes in temperature,
soil moisture Soil moisture is the water content of the soil. It can be expressed in terms of volume or weight. Soil moisture measurement can be based on ''in situ'' probes (e.g., capacitance probes, neutron probes) or remote sensing methods. Water that enters ...
, and resistance to browsing may be established, in particular secondary successional pioneer species. Clearcutting can be used by foresters as a method of mimicking a natural
disturbance Disturbance and its variants may refer to: Math and science * Disturbance (ecology), a temporary change in average environmental conditions that causes a pronounced change in an ecosystem * Disturbance (geology), linear zone of faults and folds ...
and increasing primary successional species, such as poplar ( aspen), willow and black cherry in
North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
. Clearcutting has also proved to be effective in creating animal habitat and browsing areas, which otherwise would not exist without natural stand-replacing disturbances such as wildfires, large scale windthrow, or avalanches. Clearcuts are used to help regenerate species that cannot compete in mature forests. A number of them are aspen, jack pine and, in areas with poor soils, oaks—are important species for both game and nongame wildlife species. Clearcutting can also lead to increased vascular-plant diversity in the area. This is most pronounced after a couple years of clearcutting and in herb-rich forests where scarification took place. No significant changes in water temperature were observed when patch clearcutting was done 100 feet away from a river. This suggests that patch clearcutting is a possible solution to concerns about changes in water temperature due to clearcutting. The effects of clearcutting on soil nutrient content were not examined in this study. More recently, forest managers have found that clearcutting oak stands helps regenerate oak forests in areas of poor soil. The tree canopies in oak forests often shade out the ground, making it impossible for newly sprouted oaks to grow. When the mature trees are removed, the saplings stand a chance of recruiting into the forest.


Effects on wildlife

Clearcutting's main destruction is towards habitats, where it makes the habitats more vulnerable in the future to damage by insects, diseases, acid rain, and wind. Removal of all trees from an area destroys the physical habitats of many species in wildlife. Also, clearcutting can contribute to problems for ecosystems that depend on forests, like the streams and rivers which run through them. In Canada, the black-tailed deer population is at further risk after clearcutting. The deer are a food source for wolves and cougars, as well as First Nations and other hunters. While deer may not be at risk in cities and rural countryside, where they can be seen running through neighbourhoods and feeding on farms, in higher altitude areas they require forest shelter.


In Maine

In Maine, a form of land management known as Outcome Based Forestry (OBF) allows for a wide range of harvesting as long as the removed trees do not exceed the amount of tree growth. Since implemented, this program has led to large-scale clearcutting and monoculture tree planting, and research by the University of Maine's Sustainability Solutions Initiative has found that the 8 million acres of certified forest land in (primarily northern) Maine is being
overharvested Overexploitation, also called overharvesting, refers to harvesting a renewable resource to the point of diminishing returns. Continued overexploitation can lead to the destruction of the resource, as it will be unable to replenish. The term ap ...
, leading to reduced long-term stability of
timber harvest Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidding, on-site processing, and loading of trees or logs onto trucks or skeleton cars. Logging is the beginning of a supply chain ...
s and increased erosion and pollution in the watershed. These practices have sparked environmental justice concerns regarding the health and well-being of foresters and locals.


See also

*
Amazon rainforest The Amazon rainforest, Amazon jungle or ; es, Selva amazónica, , or usually ; french: Forêt amazonienne; nl, Amazoneregenwoud. In English, the names are sometimes capitalized further, as Amazon Rainforest, Amazon Forest, or Amazon Jungle. ...
*
Clearcutting in British Columbia When logging began in British Columbia, Canada, in the late 19th century, the overriding concern was to harvest timber in the most economical fashion. Reforestation, aesthetics and protection of fish and wildlife habitat were not issues of great ...
*
Even-aged timber management Even-aged timber management is a group of forest management practices employed to achieve a nearly coeval cohort group of forest trees. The practice of even-aged management is often pursued to minimize costs to loggers. In some cases, the practice ...
* Land clearing in Australia *
List of tree species by shade tolerance A list of tree species, grouped generally by biogeographic realm and specifically by bioregions, and shade tolerance. Shade-tolerant species are species that are able to thrive in the shade, and in the presence of natural competition by other plan ...
– shade intolerant and some intermediate species are primarily regenerated with clearcuts *
Seed production and gene diversity Genetic diversity is often a major consideration in e g forest crops. Group coancestry of a population Consider the gene pool of a seed orchard crop or other source of seeds with parents. The gene pool is large as there are many seeds in a seed cr ...


References

* Roy, Vincent; Ruelb, Jean-Claude and Plamondon, André P. (1999)
"Establishment, growth and survival of natural regeneration after clearcutting and drainage on forested wetlands."
''Forest Ecology and Management'', Volume 129, Issues 1–3, 17 April 2000, pp. 253–267.


External links



* ttps://digital.library.unt.edu/govdocs/crs/search/?q=clearcutting&t=fulltext&nlow=&nhi= Congressional Research Service (CRS) Reports regarding Clearcutting, accessed 14 December 2009br>Forest Policy Research page: California citizens to stop Sierra Pacifics plan to clearcut one million acres of Sierra forest, accessed 14 December 2009Ancient Forest News - Clearcutting threatens black-tailed deer
* {{Authority control Forest management Deforestation Environmental controversies