This article is about cutting, processing, and moving trees. For electronic recording of events, seeLogging (computing). For other uses, seeLog (disambiguation).
Logging is the process of cutting, processing, and movingtrees to a location fortransport. It may includeskidding, on-site processing, and loading of trees orlogs ontotrucks[1] orskeleton cars. Inforestry, the term logging is sometimes used narrowly to describe the logistics of moving wood from the stump to somewhere outside theforest, usually asawmill or alumber yard. In common usage, however, the term may cover a range of forestry orsilviculture activities.
Logging is the beginning of a supply chain that provides rawmaterial for many products societies worldwide use forhousing,construction,energy, and consumerpaper products. Logging systems are also used to manageforests, reduce the risk ofwildfires, and restoreecosystem functions,[2] though their efficiency for these purposes has been challenged.[3]
Logging frequently has negative impacts. The harvesting procedure itselfmay be illegal, including the use of corrupt means to gain access to forests; extraction without permission or from a protected area; the cutting of protected species; or the extraction of timber in excess of agreed limits.[4] It may involve the so-called "timber mafia".[5][6] Excess logging can lead to irreparable harm to ecosystems, such asdeforestation andbiodiversity loss.[7][8] Infrastructure for logging can also lead to otherenvironmental degradation. These negative environmental impacts can lead toenvironmental conflict.[7][8] Additionally, there is significant occupational injury risk involved in logging.
Logging can take many formats.Clearcutting (or "block cutting") is not necessarily considered a type of logging but a harvesting or silviculture method. Cutting trees with the highest value and leaving those with lower value, often diseased or malformed trees, is referred to ashigh grading. It is sometimes called selective logging, and confused withselection cutting, the practice of managing stands by harvesting a proportion of trees.[9] Logging usually refers to above-ground forestry logging. Submerged forests exist on land that has been flooded by damming to createreservoirs. Harvesting trees from forests submerged by flooding or dam creation is calledunderwater logging, a form of timber recovery.[10]
Clearing 150,000 trees at Cwmcarn Forest, Ebbw Valle, Wales
Clearcutting, or clearfelling, is a method of harvesting that removes essentially all the standing trees in a selected area. Depending on management objectives, a clearcut may or may not have reserve trees left to attain goals other than regeneration,[1] including wildlife habitat management, mitigation of potential erosion or water quality concerns.Silviculture objectives for clearcutting, (for example, healthy regeneration of new trees on the site) and a focus onforestry distinguish it fromdeforestation. Other methods includeshelterwood cutting,group selective,single selective,seed-tree cutting,patch cut, andretention cutting.[citation needed]
Trees are felled and thendelimbed and topped at the stump. The log is then transported to the landing, where it isbucked and loaded on a truck. This leaves theslash (and the nutrients it contains) in the cut area, where it must be further treated if wild land fires are of concern.[citation needed]
Trees and plants are felled and transported to the roadside with top and limbs intact. There have been advancements to the process which now allows a logger orharvester to cut the tree down, top, and delimb a tree in the same process. This ability is due to the advancement in the style felling head that can be used. 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 bechipped and used for the production of electricity or heat. Full-tree harvesting also refers to utilization of the entire tree including branches and tops.[11] 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, however, depending on the species, many of the limbs are often broken off in handling so the result may not be as different from tree-length logging as it might seem.[citation needed]
Cut-to-length logging is the process of felling, delimbing, bucking, and sorting (pulpwood, sawlog, etc.) at the stump area, leaving limbs and tops in the forest.Mechanical harvesters fell the tree, delimb, and buck it, and place the resulting logs in bunks to be brought to the landing by askidder orforwarder. This method is routinely available for trees up to 900 mm (35 in) in diameter.
Timber floating in Vilnius, 1873Logging with Belarus MTZ-82-L in Estonia 2021
Logging methods have changed over time, driven by advancements in transporting timber from remote areas to markets. These shifts fall into three main eras: the manual logging era before the 1880s, the railroad logging era from the 1880s toWorld War II, and the modern mechanized era that began after the war.[12]
In the early days, felled logs were transported using simple methods such as rivers to float tree trunks downstream to sawmills or paper mills. This practice, known aslog driving ortimber rafting, was the cheapest and most common. Some logs, due to high resin content, would sink and were known as deadheads. Logs were also moved with high-wheel loaders, a set of wheels over ten feet tall, initially pulled by oxen.[13]
As the logging industry expanded, the 1880s saw the introduction of mechanized equipment like railroads and steam-powered machinery, marking the beginning of therailroad logging era. Logs were moved more efficiently by railroads built into remote forest areas, often supported by additional methods like high-wheelloaders, tractors andlog flumes.[14] The largest high-wheel loader, the "Bunyan Buggie," was built in 1960 for service in California, featuring wheels 24 feet (7.3 m) high.[15]
After World War II, mechanized logging equipment, including chainsaws, diesel trucks, andCaterpillar tractors, transformed the logging industry, making railroad-based logging obsolete. With the advent of these tools, transporting logs became more efficient as new roads were constructed to access remote forests. However, in protected areas likeUnited States National Forests and designatedwilderness zones, road building has been restricted to minimize environmental impacts such as erosion inriparian zones.
Today, heavy machinery such asyarders andskyline systems are used to gather logs from steep terrain, while helicopters are used forheli-logging to minimize environmental impact.[16] Less common forms of logging, likehorse logging and the use of oxen, still exist but are mostly superseded.[17]
Logging is a dangerous occupation. In the United States, it has consistently been one of the most hazardous industries and was recognized by theNational Institute for Occupational Safety and Health (NIOSH) as a priority industry sector in theNational Occupational Research Agenda (NORA) to identify and provide intervention strategies regarding occupational health and safety issues.[18][2]
In 2008, the logging industry employed 86,000 workers and accounted for 93 deaths. This resulted in a fatality rate of 108.1 deaths per 100,000 workers that year. This rate is over 30 times higher than the overall fatality rate.[19] Forestry/logging-related injuries (fatal and non-fatal) are often difficult to track through formal reporting mechanisms. Thus, some programs have begun to monitor injuries through publicly available reports such as news media.[20] The logging industry experiences the highest fatality rate of 23.2 per 100,000full-time equivalent (FTE) workers and a non-fatal incident rate of 8.5 per 100 FTE workers. The most common type of injuries or illnesses at work includemusculoskeletal disorders (MSDs), which include an extensive list of "inflammatory and degenerative conditions affecting themuscles,tendons,ligaments,joints,peripheral nerves, and supportingblood vessels."[21] Loggers work with heavy, moving weights, and use tools such aschainsaws and heavy equipment on uneven and sometimes steep or unstableterrain. 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.[citation needed]
Traditionally, the cry of "Timber!" developed as a warning alerting fellow workers in an area that a tree is being felled, so they should be alert to avoid being struck. The term "widowmaker" for timber, typically a limb or branch that is no longer attached to a tree, but is still in the canopy either wedged in a crotch, tangled in other limbs, or miraculously balanced on another limb demonstrates another emphasis onsituational awareness as a safety principle.[22]
In British Columbia, Canada, the BC Forest Safety Council was created in September 2004 as a not-for-profit society dedicated to promoting safety in the forest sector. It works with employers, workers, contractors, and government agencies to implement fundamental changes necessary to make it safer to earn a living in forestry.[23]
The risks experienced in logging operations can be somewhat reduced, where conditions permit, by the use of mechanical tree harvesters, skidders, and forwarders.[24]
Horse Logging in Wales
Log transportation by rail in British Columbia in 1920
^'Logging emits three times as much carbon dioxide into the atmosphere per acre as wildfire alone. Most of the tree parts unusable for lumber – the branches, tops, bark and sawdust from milling – are burned for energy, sending large amounts of carbon into the atmosphere. In contrast, wildfire releases a surprisingly small amount of the carbon in trees, less than 2 percent. Logging in U.S. forests is now responsible for as much annual greenhouse gas emissions as burning coal.' Chad Hanson, Michael Dorsey,'The Case Against Commercial Logging in Wildfire-Prone Forests,'New York Times 30 July 2022.