Logging

Logging is the process in which trees are felled (cut down) usually as part of a timber harvest. Timber is harvested to supply raw material for the wood products industry including logs for sawmills and pulp wood for the pulp and paper industry. Logging can also remove wood for forest management goals. Logging is controversial due to its environmental and aesthetic impacts.

Use of the term logging in Forestry

In forestry the term logging is sometimes used in a narrow sense concerning the logistics of moving wood from the stump to somewhere outside the forest, often a mill. In common usage however the term may be used more generally to mean a range of forestry or silviculture activities. For example the practice of the removal of a small number of commercial valuable trees from the forest has been called selective logging perhaps confused with selection cut. Illegal logging refers to what in forestry might be called timber thief. In common usage what is sometimes called clearcut logging is not necessarily considered a type of logging but a harvest method and is simply called clearcutting or block cutting. In the forest products industry logging companies may be referred as logging contractors.

Logging usual refers to above-ground forestry logging. Submerged forests exist on land that has been flooded to create artificial dams and reservoirs, and trees have started to be felled there too (see underwater logging).

Logging and forestry

The two main stakeholders in most logging operations are the landowner and the logging contractor. Prior to a large harvest a landowner will often hire a consulting forester. Owners of large industrial tracts may employ their own foresters. During planning for the harvest the forester will determine how best to meet the landowner's objectives, including the silvicultural system to be used, even-aged or uneven-aged management, layout of roads and landings. If a selection cut is planned the forester will mark the trees intended to be cut or if a clear cut which blocks are to be harvested. A well-managed forest will be harvested according to a forest management plan. This plan should include areas off-limits to cutting such as sensitive habitat, vernal pools and riparian zones.

Logging methods

The above operations can be carried out by different methods, of which the following three are considered industrial methods:

Tree-length logging: Trees are felled and then delimbed and topped at the stump. The log is then transported to the landing, where it is bucked and loaded on a truck. This leaves the slash (and the nutrients it contains) in the cut area where it must be further treated if wildland fires are of concern.

Full-tree logging: Trees are felled and transported to the roadside with top and limbs intact. The trees are then delimbed, topped, and bucked at the landing. This method requires that slash be treated at the landing. In areas with access to cogeneration facilities, the slash can be chipped and used for the production of clean electricity or heat. Full-tree harvesting also refers to utilization of the entire tree including branches and tops. ^[1] This technique removes both nutrients and soil cover from the site and so can be harmful to the long term health of the area if no further action is taken.

Cut-to-length logging: Trees are felled, delimbed, bucked, and sorted (pulpwood, sawlog, etc.) at the stump area, leaving limbs and tops in the forest. Harvesters fell the tree, delimb and buck it, and place the resulting logs in bunks to be brought to the landing by the forwarder.

Operations

A timber harvest can consist of the following operations, although not necessarily in the following order.

Pre-logging: Planning - Identifying optimal timing, access, and layout of harvest.

Permitting - Regulatory review can include public notification, environmental assessment, taxes, and fees.

Sale - Many timberland owners employ their own loggers, while others hire or sell the right to log to a logging company.

Accessing - Logging roads, logging camps, and weighing stations are built or repaired as needed.

Marking - The area or individual trees to be harvested are clearly identified.

Measuring - Assessing the volume of timber that will be produced by the harvest.

Marketing - Arranging supply contracts with timber customers, this may be undertaken through competitive sale methods or as part of a negotiation with preferred customers.

Logging: Felling - The standing tree is cut down or felled by chainsaw, harvester, or feller buncher.

Processing - The tree is turned into logs by removing the limbs (delimbing) and cutting it into logs of optimal length (bucking).

Stump to landing - The felled tree or logs are moved from the stump to the landing. Ground vehicles can pull, carry, or shovel the logs. Cable systems can pull logs to the landing. Logs can also be flown to the landing by helicopter.

Landing to mill - The logs are commonly transported to the mill or port by truck, but in the past, this has been done by train, by driving the logs downstream, or by pulling them as a floating log raft.

Post-logging: Burning - Burning logging debris and other woody material on the site can reduce future fire risk and release nutrients.

Herbicide - Eliminating competing seedlings and brush to speed growth of the planted seedlings

Ground preparation - Cultivation of the soil to create suitable planting positions. This operation may include some element of land drainage in wet areas if soil saturation affects seedling survival / growth potential.

Replanting - Dropping seeds or manual planting of seedlings

Road deconstruction - Subsequent erosion and landsliding from old roads can be reduced by installing waterbars, pulling fill from stream crossings, and putting excavated materials back to reform the original topography.

Logging and safety

Logging is by some measures a dangerous occupation. Loggers work with heavy, moving weights and the use of tools such as chainsaws and heavy equipment on uneven and sometimes unstable terrain. Loggers also deal with severe environmental conditions such as inclement weather and severe heat or cold. An injured logger is often far from professional emergency treatment. The risks experienced in logging operations can be somewhat reduced, where conditions permit, by the use of mechanical tree harvesters and forwarders.

Logging and the environment

File:Logskidder7981.JPG

Grapple Skidder on a clearcut plot, Johnsonville, South Carolina.

The many impacts of logging on the environment can be divided into two broad categories, the timber harvest itself, that is, the removal of trees from the forest, and secondly the impact caused by logging operations such as felling or dragging trees and operation of machinery in the forest.

Impact of loss of trees

Removal of trees alters species composition, the structure of the forest, and can cause nutrient depletion. Loss of trees also can lead to habitat loss, prominently in high-value, ecologically sensitive lands. Loss of trees adjacent to streams can increase water temperatures. Harvesting adjacent to streams can increase sedimentation and turbidity in streams, lowering water quality and degrading riparian habitat. Some of the most clearly noticeable effects of large-scale clear-cutting, including effects on stream corridors, has been seen in the American Pacific Northwest, where endangered salmon spawning and rearing habitat has been damaged. A forest managed primarily for wood production will typically consist of young, vigorous, fast-growing trees. Such a forest may lack areas with late-succession characteristics, including older trees, required by some species. Good forest management requires that such areas be set aside to protect species that may be rare or endangered.

Impact of logging operations

Modern ground based logging operations require the use of heavy machinery in the forest. In some areas roads must be built which often causes habitat fragmentation and increased edge effect. The use of heavy machinery in a forest can cause soil compaction. Harvesting on steep slopes can lead to soil erosion, landslides, and water turbidity. Logging on saturated soils can cause ruts and change drainage patterns. Harvest activity near wetlands or vernal pools can degrade the habitat. Forest machines use oils which, if not handled carefully, can cause pollution. Roadbuilding for access to timber in frontier forests often opens up areas previously not accessible, which facilitates further development such as farming. Logging roads and operations increase the risk of colonization of forest areas by invasive exotics, especially in the eastern North American hardwood and western evergreen forests (see also Gypsy moth). However, the effect of logging can be necessary to promote the growth of younger trees which must take the place of the older and dying ones.

Mitigation

These problems can be mitigated by using low-impact logging and best management practices, which set standards for reducing erosion from roads. Damage to streams and lakes can be reduced by not harvesting riparian strips. Ecologically important lands are sometimes set aside as reserves. Technological advances in logging equipment are reducing ruts and soil disturbance. Processors and Forwarders with Caterpillar tracks or other designs to lower ground pressure help to reduce machine impact ^[2].

Benefits

Logging can also have positive effects on the environment by removing damaged or diseased trees or both, and opening up the canopy to promote growth of smaller, healthier trees. Branches, snags, and other non-marketable parts of the tree provide shelter for wildlife. Underbrush that would not otherwise grow due to lack of sunlight thrives, and is an important food source for browsing mammals. Select cutting can improve the forest and bring to market trees that would otherwise decompose. In the 19th and early 20th century, logged over areas were sometimes sold or donated to the state, or forfeited for back taxes. Following the maturation of new growth, usually of different tree species, this acreage became the basis of certain outstanding recreation areas, including the White Mountain National Forest.

Logging and the environmental movement

The logging industry is often portrayed[1] in the media, popular culture and by many environmental groups as an ecologically destructive practice. Criticism of logging may include protest against the idea of using forest products for human use or may be a criticisms of a specific forestry practice such as clear cutting. It may also include protest against illegal logging. Perhaps most commonly anti-logging activism refers to criticisms of forest policy for example percentage of forest to be reserved for habitat or cutting of old-growth timber or some specific forest.

While logging is the cause of severe environmental degradation in some areas, notably tropical forests, logging can be done in a manner that minimizes harm to the environment. In developed countries agriculture, livestock grazing, mineral mining, the petroleum industry and urban sprawl are greater contributors to deforestation and ecological degradation than is the timber industry. As an example, Mary M. Berlik, David B. Kittredge and David R. Foster of Harvard University^[3] cite that a house built out of steel, plastic and concrete has a higher life cycle assessment or life-cycle cost and requires more energy and non-renewable resources to produce than a house built with wood products. It has also been contended that logging bans, without a decrease in demand for wood products, simply shifts harvests to other areas^[4]

In developed countries, most timber harvests are carried out in a way that attempts to minimize the environmental impact and to maintain the long-term productivity of the forest. In some forests, management has focused less on trees as a crop and more on "multiple-use" in which forest are managed for recreation, habitat and watershed protection. In some developing countries, timber harvesting is often performed without regard to environmental harm or future forest productivity. Unsustainable logging practices and illegal logging are responsible for the degradation of habitat and watersheds. Construction of logging roads into the world's remaining primary forest opens areas for degradation or conversion to other uses. In tropical forest, reducing the impact of logging is a high priority for many environmental organizations.

Unsustainable and unregulated logging in the United States during the late 19th century and early 20th century was part of the impetus in creating national forests.

Recent anti-logging campaigns have focused on the carbon released both from the trees and the soil as a result of logging operations.

Logging roads

Logging roads are constructed to provide access to the forest for logging and other forest management operations. These are commonly narrow and unpaved. Logging trucks, which, when loaded, can carry up to 25,000 kg are generally given right of way.

Logging roads are often the major source of sediment from logging operations. Construction of these roads, especially on steep slopes, can increase the risk of erosion and landslides. This can increase downstream sedimentation and can continue long after operations are completed in the area. The decommissioning of these roads involves the restoring of natural habitat, which can cost as much as the original road construction.

Sources

Notes and References

External links

Forest Resources Association, Inc.
A Large Searchable Digital collection of Historical Logging Images University of Washington Libraries: Digital Collections:
- Darius Kinsey Photographs Images from the period 1890-1939, documenting the logging industry in Washington State. Includes images of loggers and logging camps, skid roads, donkey engines, loading operations, logging trucks and railroads.
- Clark Kinsey Photographs Over 1000 images by commercial photographer Clark Kinsey documenting the logging and milling camps and other forest related activities in Washington State, ca. 1910-1945.
- Industry and Occupations Photographs An ongoing and expanding collection devoted to the workers in the Pacific Northwest from 1880s-1940s. Many occupations and industries are represented including the logging and lumber industry.
- Man to Machine: Peninsula Logging Online museum exhibit based upon the Clark Kinsey Logging Photographs Collection and the recollections of Harry C. Hall, who worked as a logger on the Olympic Peninsula in the early 1900s. Includes a video on the Hobi family logging history (late 1800s – early 1900s).

[1] res.ca.gov

[2] Forestry Commission Technical Note 11

[3] Harvard Forestry

[4] Berlik, J.

[1]

[2]

[3]

[4]