Outline of forestry

Outline of forestry

The following outline is provided as an overview of and guide to forestry:

Forestrythe art and science of managing forests, tree plantations, and related natural resources. Forest ecosystems have come to be seen as the most important component of the biosphere,[1] and forestry has emerged as a vital field of science, applied art, and technology. The main goal of forestry is to create and implement systems that allow forests to continue a sustainable continuation of environmental supplies and services. The challenge of forestry is to create systems that are socially accepted while sustaining the resource and any other resources that might be affected.[2]

Focus of forestry

  • Treeorganism, whose species, age, vitality, growth, health, and size, are considered individually or more often, as part of a whole;
  • Forestdefined as either a geographic area or delineated by the general composition of individuals;
  • Biomeecologically defined by its forest structure, leaf types, tree spacing, and climate
General Forested Biomes
Boreal
Boreal forest in Finland clipped.jpg
Taiga
Temperate
Pinus echinata USFWS retouched.jpg Fall foliage on the Black River clipped.jpg Korkeichenwald bei Evora02 clipped.jpg
Coniferous Broadleaf and mixed Mediterranean
Tropical/Subtropical
Tropical conifers El Salvador.jpg Gabon tropical rainforest.jpg Nilgiri Hills trees.jpg
Coniferous Moist broadleaf Dry broadleaf
Wetlands
Cartagena de Indias, manglar clipped.jpg Picea mariana taiga clipped.jpg Cypress Swamp modified.jpg
Mangroves Bogs Swamps
Other
Avenida brasil clipped.jpg Cloquet riparian forest clipped.jpg
Urban Riparian

Branches of forestry

  • Dendrologyinvolves the study and identification of economically useful tree species
  • Forest ecologystudies the patterns and processes of a forest ecosystem
  • Silvicultureis the art and science of controlling the establishment, growth, composition, health, and quality of forests to meet specific objectives
  • Forest managementcomprises the overall administrative, economic, legal, and social aspects of forest regulation
  • Forest mensurationincorporates quantitative measurements of the forest stand to determine stand timber volume and productivity/health, and provides a basis off which management decisions can be made
  • Forest hydrologyembodies the effects of changes in forest land use on the movement, distribution, and quality of water in the ecosystem
  • Agroforestryintegration of forests into agricultural systems in order to optimize the production and positive effects within the system and minimize negative side effects of farming
  • Forest pathologyresearch of both biotic and abiotic maladies affecting the health of the forest or tree, primarily fungal pathogens and their insect vectors
  • Forest economicsstudies the impact of economics on forest management decisions
  • Urban forestryentails the care and management of urban tree populations for the purpose of improving the urban environment
  • Energy forestryincludes specifically managing for the production of energy from biomass or biofuel derived from a fast-growing species of tree or woody shrub

Occupations in forestry

  • Foresterprofessional chiefly responsible for the management of forests, requires a Bachelor of Science degree in most countries
    Two USFS foresters discussing firefighting tactics.
  • Forest technicianindividual primarily responsible for the marking of timber sales and on-ground land management, oftentimes requires a two-year Associate of Science degree
  • Lumberjackthe typical feller of trees and harvester of the lumber, duties can also include:
  • Log scalingmeasurement of felled trees to determine the volume of wood going to the manufacturer
  • Log buckingdelimbing and partitioning of trees into logs
  • Log drivingtransportation of logs on a river or lake downstream to the mill
  • Arboristprofessional responsible for the maintenance of individual trees in an urban forest
  • Resin extractorlaborer who extracts resin from pine trees
  • Rubber tapperlaborer who extracts natural rubber from tropical rubber trees
  • Fire lookoutperson assigned to spot for fires/smoke atop a fire lookout tower
  • Hotshot crew/Handcrewa group of wildland firefighters specialized in fire suppression tactics
  • Smokejumperfirefighters who parachute into remote areas to fight wildland fires

Management focuses

Main article: Forest management
  • Analog forestrya management focus that seeks to establish a tree-dominated ecosystem that is similar in architectural structure and ecological function to the naturally occurring climax and sub-climax vegetation community
  • Community forestrycombination of forest conservation with rural development and poverty reduction objectives, accomplished through instating a legal framework that favors profitable and sustainable forest management
  • Ecoforestryemphasizes practices which strive to protect and restore ecosystems
  • Hardwood timber productionprocess of managing stands of deciduous trees to maximize woody output
  • Tree breedingmethod of genetically modifying/selecting forest stock for improved growth or vigor characteristics
  • Short rotation forestrymanaging a forest that utilizes fast-growing species as a bio-based energy crop for use in power stations, alone or in combination with other fuels such as coal
  • Sustainable forest managementemphasizes practices that maintain forest biodiversity, productivity, regeneration capacity, and vitality, while continuing to fulfill relevant ecological, economic and social functions
  • Tree farma forest or woodland owned privately where timber crop production is a major management goal

Silvicultural methods

Main article: Silviculture

Site preparation

  • Controlled burnuse of fire in order to eliminate weeds, brush, or slash, or to release on-site seeds of fire-dependent species
  • Stump harvestingremoval of tree stumps either for biomass or to free up space in the soil
  • Drum choppingknocking down small trees and brush to clear the ground for planting

Planting

  • Broadcast seedingscattering of seed either by hand or mechanically over a relatively large area
  • Aerial seedingdispersing of seed from an aircraft, used especially in mountainous areas
  • Treeplantingtransplanting of juvenile seedlings into the ground at a predetermined spacing

Intermediate treatments

Natural regeneration of Acer platanoides in northern France, surrounded by woody and herbaceous competition.
  • Weedingremoval or reduction of herbaceous or woody species around seedlings
  • Cleaningremoval of competing saplings of similar age in order to favor saplings of desirable growth characteristics
  • Liberation cuttingremoval of older and established overtopping trees from desirable saplings
  • Thinningremoval of trees to favor the growth of select trees in order to maximize timber production
  • Ecological thinningremoval of trees to favor the growth of select trees in order to favor the development of wildlife habitat
  • Pruningremoval of the lateral branches on the trees in order to improve wood quality
  • Pollardingannual removal of lateral branches or main stem in order to encourage growth of branches to provide for firewood, or fruit production

Harvest rotations

Clearcuts in the foreground and background at Rattlesnake Mountain, Montana.
  • Even-aged timber management
  • Clearcuttingharvesting of all stems in a given area regardless of species and size
  • Coppicingcutting vigorous juvenile trees near the ground, regeneration comes from new shoots coming up from the stump
  • Seed-treecutting of all trees save widely spaced residual trees, which will provide natural seedstock for the following generation and are later cut
  • Uneven-aged timber management
  • Selectionharvesting of selected trees in a stand, removing either merchantable timber or to favor the growth of desirable individuals (a thinning)
  • Shelterwoodremoval of merchantable trees in succession, establishing a multiaged stand
  • Variable retentionremoval of trees of varying density across a landscape, in order to retain structural diversity
  • Other
  • Salvage loggingharvesting of trees killed by natural disturbances in order to maximize economic returns that would otherwise be lost
  • Sanitation harvestremoval of individual trees affected by a pathogen in order to diminish the possibility the entire stand being affected
  • Biomass harvestharvesting of small wood for energy purposes, either following a commercial harvest or for its own sake, such as in energy forestry
  • Underwater loggingharvesting of trees from underwater forests flooded during construction of artificial dams or reservoirs

Environmental issues pertaining to forests

  • Deforestationthe removal of trees in a forested area without sufficient regeneration, resulting in desertification in arid areas and loss of habitat and biodiversity
  • Afforestationthe process of establishing a forest on previously unforested land, for reasons of timber harvesting, conservation of biodiversity, or soil decontamination, among many
    Illegal logging in Cambodia.
  • Forest fragmentationoccurring when forests are cut down in a manner that leaves relatively small, isolated patches of forest, resulting in high amounts of edges and subsequent loss in wildlife habitat and biodiversity
  • Forest diebackwhere trees on the periphery of a stand are killed by acid rain or parasites
  • Illegal loggingthe unlawful harvest, transportation, purchase or sale of timber, contributing to deforestation, corruption, and destabilization of international markets
  • High gradingtype of selective logging that removes the highest timber quality trees, resulting in poor genetic stock for subsequent generations
  • Forest transitionshift from a period of net forest area loss (deforestation) to a period of net forest area gain (afforestation) for a given region or country

Forest resource assessment

Main article: Forest inventory or Timber cruise

Timber metrics

  • Diameter at breast height (DBH) – measurement of a tree's diameter standardized at 1.3 meters (about 4.5 feet) above the ground
  • Basal areadefines the area of a given section of land that is occupied by the cross-section of tree trunks and stems at their base
  • Tree taperthe degree to which a tree's stem or bole decreases in diameter as a function of height above ground
  • Girard form classan expression of tree taper calculated as the ratio of diameter inside the bark at 16 feet above ground to the to that outside bark at DBH, primary expression of tree form used in the United States
  • Quadratic mean diameterdiameter of the tree that coordinates to the stand's basal area
  • Leaf Area Indexthe ratio of total upper leaf surface of the forest canopy divided by the surface area of the land on which the vegetation grows
  • Tools
  • Biltmore stickutilizes ocular trigonometry to quickly measure diameter and height
    Figure demonstrating the ocular trigonometric principles behind the Biltmore stick.
  • Diameter tapecloth or metal tape that is wrapped around the bole, scaled to diameter
  • Calipertwo prongs connected to a measuring tape are placed around the most average part of the bole to determine diameter
  • Relascopemultiple-use tool that is able to find tree height, basal area, and tree diameter anywhere along the bole
  • Clinometercommon tool used to measure changes in elevation and tree height
  • Cruising rodsimilar to a caliper, calculates the number of pieces of lumber yielded by a given piece of timber by measuring its diameter
  • Hemispherical photographyestimates solar radiation and characterize plant canopy structure/density using photographs taken looking upward through an extreme wide-angle lens

Surveying techniques

  • Traversingmethod of surveying used to establish sampling plots along a line or path of travel
    A wedge prism showing a borderline tree.
  • Chainequivalent to 66 feet, widely used distance in surveying practices in the United States and other countries influenced by imperial Great Britain
  • Line plot surveyplots taken at a regular predetermined distance along the traverse path
  • Tools
  • Pacingquick method used to survey in the field, requiring calibration of one's "paces" (pair of footsteps) to a known distance (oftentimes a chain)
  • Hand compassa compact magnetic compass with a sighting device used to determine the location of plots for a given bearing
  • Wedge prismoptical instrument typically made of glass ground at slight angles to refract light passing through it from the smaller width side of the prism to the thicker width side of the prism, calibrated to a desired plot size (basal area factor)
  • Angle gaugesimilar in principle to a wedge prism, although it must be held a fixed distance from the eye
  • GPSglobal satellite navigation systems used to determine the position of oneself and plots
  • GISan information system capable of integrating, storing, analyzing, and displaying forest geographic information collected in the field

Timber volume determination

  • Site indexa species specific measure of site productivity and management options, reported as the height of dominant and co-dominant trees (site trees)in a stand at a base age such as 25, 50 and 100 years
    An increment borer with common drinking straws, a cost-effective manner often used to hold derived cores.
  • Stockinga quantitative measure of the area occupied by trees relative to an optimum or desired level of density
  • Stand Density Indexa measure of the stocking of a stand of trees based on the number of trees per unit area and DBH of the tree of average basal area
  • Volume tablea chart based on volume equations that uses correlations between certain aspects of a tree to estimate the standing volume
  • Stand density management diagrammodel that uses current stand density to project future stand composition
  • Units of measurement
  • Cordvery common measure, equivalent to 128 cubic feet (3.62 m3), corresponding to a pile of wood, bark, and air 4 feet wide by 4 feet high and 8 feet long
  • Stèreinvented in France, equivalent to a cubic meter of cut wood with space for air
  • Board footspecialized unit of measure for lumber in North America, equivalent to the volume of a one foot length of a board one foot wide and one inch thick

Stand growth assessment

  • Increment borerspecialized tool used to extract a section of wood tissue from a living tree with relatively minor injury to the tree, used often for tree growth analysis
  • Mean annual increment (MAI) – refers to the average growth per year a tree or stand of trees has exhibited at a specific age
  • Periodic annual increment (PAI) – describes the average annual change in tree diameter between the beginning and ending of a growth period, used more often than MAI for percental growth
  • Ecological yield -the amount of wood volume in any given year whose harvesting would be considered sustainable
  • Growth and yield modellingentails the creation of models of prospective tree growth and harvest yield for management purposes
  • Economics
  • Stumpagethe price charged by a land owner to loggers for the right to harvest standing timber on that land
  • Optimal rotation agethe age at which the harvesting of stumpage will generate the maximum revenue or economic yield

Harvesting

Main article: Logging

Harvesting methods

  • Fellingprocess of cutting down a tree
    A cable logging setup in Germany (1988).
  • Buckingsplitting of a felled and delimbed trees into logs
  • Scalingmeasurement of felled trees to determine the volume of merchantable wood
  • Skiddingtransportation of logs from the site of felling to the landing along the ground
  • Forwardingtransportation of logs from the site of felling to the landing above the ground, usually to minimize soil disturbance but limits the size or amount of logs that can be moved at once
  • Haulinglong-distance transportation of logs from the landing to their final destination, usually with a semi-truck but occasionally with a train
    The boom of a cut-to-length harvester with attached chainsaw cutting Pinus sylvestris in Finland.
  • Woodchippinggrinding of logs into chips for engineered wood, mulch, paper, or fuel
  • Cut-to-length logging (CTL) – an expensive but efficient system where trees are felled, delimbed, and bucked to scale directly at the felling site
  • Cable loggingskidding using a wire cable attached to the felled trees, most common in areas with steep topographic relief, variations include
  • High lead logginga cable is anchored to a tree at the top of the hill:
  • Skyline logginga carriage is used alongside the main cable to provide leverage
  • Shovel loggingtransport of multiple logs close to the logging road using a stationary loader, often used to minimize soil disturbance
  • Heli-loggingtransport of logs from the forest to the landing via helicopter, most commonly used in inaccessible areas or to minimize impact on the soil
  • Log drivingtransportation of individual logs on a waterway to a mill or port downstream
    A forwarder loading felled Picea abies near Hedmark, Norway.
  • Timber raftingtransportation downstream of multiple logs bundled together into a raft, considered less dangerous than log driving

Harvesting tools

  • Timber felling
  • Hand
  • Axeprimitive tool used felling and splitting
  • Chainsawportable mechanized all-purpose saw, the most common tool used in hand-felling
    A loader lifting logs off a semi at Port Chalmers, within the city of Dunedin, New Zealand.
  • Crosscut sawsaws that have teeth that are designed to cut wood at a right angle to the direction of the wood grain, used for felling and bucking
  • Bucksawa type of crosscut saw used by one or two people to buck felled trees into sawlogs
  • Mechanized
  • Feller bunchervehicle with an attachment that can rapidly cut and gather several smaller trees before felling them
    Timber rafts being floated into the city of Shlisselburg, in northwestern Russia (1909).
  • Harvesterfirst half of the CTL system, vehicle that cuts, delimbs, and bucks the logs "to length"
  • Log transportation
  • Ground
  • Peaveya traditional tool consisting of a wooden lever handle with a movable metal hook with a sharp tip, used to spear the log for handling and moving
  • Cant Hooktool with the same premise as the peavey but with blunt teeth-bearing tip
  • Yarderin cable logging, a piece of equipment utilizing a pulley system of cables to pull or fly logs from the stump to the landing
  • Forwardersecond half of the CTL system, the vehicle that carries logs clear off the ground from the felling site to the roadside landing
  • Skiddervehicle that drags logs along the ground from the felling site to the roadside landing
  • Michigan logging wheelshistorical skidder, consisting of a specially designed large set of wooden wagon wheels and could be used in unfrozen soil conditions
  • Skid conea steel or plastic cone placed on the end of a log while being skidded, in order to ease its transportation or protect residual trees
  • Water
  • Splash dama dam built to temporarily raise the water level of a river to float timber downstream
  • Flumechutes specifically constructed to transport lumber and logs down mountainous terrain to a sawmill by using flowing water.
  • Timber slidechutes constructed parallel to a river in order to avoid damage to timber rafts caused by rapids or waterfalls
  • Boombarriers placed in a river, designed to collect and or contain floating logs felled from nearby forests

Forest products

Main article Forest product, or Wood processing
A harvest landing with slash/biomass on the left, followed by pulpwood and sawlogs in Espoo, Finland.

Primary forest products

Main article Wood

  • Lumberor timber, the raw material for the construction of buildings or furniture making
  • Papermade from wood pulp derived from the timber stock pulpwood

Main article Engineered wood

Secondary forest products

  • Fuel
Main article: Wood fuel and Biomass
  • Byproducts
  • Ecosystem services
Main: Ecosystem services

History of forestry

Main article: History of forestry

Notable people

  • Georg Ludwig Hartig (17641837) – a prominent forest manager, author, and founder of many forestry universities in Germany, including one at the University of Berlin
  • Franklin Hough (18221885) – chief of the United States Division of Forestry, the "father of American forestry"
  • Bernhard Fernow (18511923) – laid the groundwork for the United States Forest Service, founding dean of the first professional forestry school in the United States
  • Dietrich Brandis (18241907) – considered the "father of tropical forestry".
  • Gifford Pinchot (18651946) – first chief of the United States Forest Service and proponent of the Wise Use Movement
  • Carl A. Schenck (18681955) – responsible for incorporating German scientific management techniques into American forest management, and founder of Biltmore Forest School, the first forestry school in the United States
  • Károly Bund (18691931) – an early academic and practical forester whose work in the Hungarian National Forestry Association increased treeplanting and intensified efforts to protect natural forests, indigenous tree species, and forestry workers in AustriaHungary
  • Aldo Leopold (18871948) – cofounder of The Wilderness Society along with Robert Marshall (below), prominent naturalist writer and environmental ethicist
  • Robert Marshall (19011939) – cofounder of The Wilderness Society, which helped pass the Wilderness Act, which created the first legal definition of wilderness and conserved some 9,100,000 acres (37,000 km2) of national forest land in the United States
  • Walter Bitterlich (19082008) – world-renowned Austrian scientist, best known for the invention of variable plot sampling
  • Sakari Pinomäki (?) – pioneer of mechanized forest harvesting vehicles, decreasing the time required for harvesting and risk to loggers
  • Stephen C. Sillett (1968- ) – revolutionized the approach and methodology of studying plant and animal life in old growth canopies of large trees
  • Kenneth Dupee Swan (18871970) – notable photographer for the USDA Forest Service

Lists

  • List of forestry universities and collegesinstitutions worldwide leading to a degree in forestry
  • List of woodscommonly used in the timber and lumber trade
  • List of tree species by shade tolerancetree grouped by shade tolerance, a determinant in successional status

Allied sciences

  • Ecologywhose principles are the main scientific basis of forestry
    Increment borer cores of Pinus sylvestris, whose varying rates of annual tree growth are in response to external environmental conditions.
  • Conservation biologyconscientious management of forests can preserve or enhance biodiversity of dependent species
  • Botanystudy of plant life and development that explains the biological basis of trees, such as structure, growth, reproduction, metabolism, response to disease, and chemical properties
  • Soil sciencephysical, chemical, and biological properties of soil greatly determines the success of tree species and individuals
  • Ecophysiologythe study of an organism's physiology to environmental conditions that explains the success of a particular tree species' growth, reproduction, survival, and abundance
  • Dendrochronologymethod of scientific dating based on the analyses of tree-ring growth patterns, analysis of long-lived individual trees can provide insight into climatic conditions of the past

See also

References

  1. ^ http://www.tutorvista.com/content/biology/biology-iv/ecosystem/ecosystem-definition.php ecosystem part of biosphere
  2. ^ "Forestry." Gale Encyclopedia of Science. Thomson Gale, 2001. NA. General OneFile. Gale. 12 Oct. 2009 <http://find.galegroup.com/gps/start.do?prodId=IPS>.

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