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Tree plantation

From Wikipedia, the free encyclopedia
(Redirected fromTree farm)
Type of forest planted for high volume production of wood
For the act of planting trees, seeTree planting.
Apine plantation in the United States

Atree plantation, forest plantation,plantation forest,timber plantation ortree farm is a forest planted for high volume production of wood, usually by planting one type of tree as amonoculture forest. The termtree farm also is used to refer totree nurseries andChristmas tree farms.Plantation forestry can produce a high volume of wood in a short period of time. Plantations are grown by state forestry authorities (for example, theForestry Commission in Britain) and/or the paper and wood industries and other private landowners (such asWeyerhaeuser,Rayonier andSierra Pacific Industries in the United States orAsia Pulp & Paper in Indonesia).Christmas trees are often grown on plantations, and in southern and southeastern Asia,teak plantations have recently replaced the natural forest.

A plantation ofDouglas-fir inWashington,U.S.

Industrial plantations are actively managed for the commercial production of forest products. Industrial plantations are usually large-scale. Individual blocks are usually even-aged and often consist of just one or two species. These species can be exotic or indigenous. The plants used for the plantation are often genetically altered for desired traits such as growth and resistance to pests and diseases in general and specific traits, for example in the case of timber species, volumic wood production and stem straightness.Forest genetic resources are the basis for genetic alteration. Selected individuals grown inseed orchards are a good source for seeds to develop adequate planting material.

Wood production on a tree plantation is generally higher than that of natural forests. While forests managed for wood production commonly yield between 1 and 3 cubic meters per hectare per year, plantations of fast-growing species commonly yield between 20 and 30 cubic meters or more per hectare annually; aGrand Fir plantation inScotland has a growth rate of 34 cubic meters per hectare per year,[1] andMonterey Pine plantations in southernAustralia can yield up to 40 cubic meters per hectare per year.[2] In 2000, while plantations accounted for 5% of global forest, it is estimated that they supplied about 35% of the world's roundwood.[3]

The highest share of plantation forest is in South America, where this forest type represents 99 percent of the total planted-forest area and 2 percent of the total forest area. The lowest share of plantation forest is in Europe, where it represents 6 percent of the planted forest estate and 0.4 percent of the total forest area. Globally, 44 percent of plantation forests are composed mainly of introduced species. There are large differences between regions: for example, plantation forests in North and Central America mostly comprise native species and those in South America consist almost entirely of introduced species.[4]

Growth cycle

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Main article:Silviculture
  • In the first year, the ground is prepared usually by the combination of burning, herbicide spraying, and/orcultivation and then saplings are planted by human crew or by machine. The saplings are usually obtained in bulk from industrial nurseries, which may specialize in selective breeding in order to produce fast growing disease- and pest-resistant strains.
  • In the first few years until the canopy closes, the saplings are looked after, and may be dusted or sprayed with fertilizers or pesticides until established.
  • After the canopy closes, with the tree crowns touching each other, the plantation is becoming dense and crowded, and tree growth is slowing due to competition. This stage is termed 'pole stage'. When competition becomes too intense (forpine trees, when thelive crown is less than a third of the tree's total height), it is time to thin out the section. There are several methods forthinning, but where topography permits, the most popular is 'row-thinning', where every third or fourth or fifth row of trees is removed, usually with aharvester. Many trees areremoved, leaving regular clear lanes through the section so that the remaining trees have room to expand again. The removed trees aredelimbed, forwarded to the forest road, loaded onto trucks, and sent to a mill. A typical pole stage plantation tree is 7–30 cm indiameter at breast height (dbh). Such trees are sometimes not suitable fortimber, but are used as pulp for paper andparticleboard, and as chips fororiented strand board.
  • As the trees grow and become dense and crowded again, the thinning process is repeated. Depending on growth rate and species, trees at this age may be large enough for timber milling; if not, they are again used as pulp and chips.
  • Around year 10-60 the plantation is now mature and (in economic terms) is falling off the back side of its growth curve. That is to say, it is passing the point of maximum wood growth per hectare per year, and so is ready for the final harvest. All remaining trees are felled, delimbed, and taken to be processed.
  • The ground is cleared, and the cycle can be restarted.

Some plantation trees, such as pines and eucalyptus, can be at risk offire damage because their leaf oils and resins are highly flammable.[5][6] Conversely, an afflicted plantation can in some cases be cleared of pest species cheaply through the use of aprescribed burn, which kills all lesser plants but does not significantly harm the mature trees.

Types

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Eucalyptus

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This section is an excerpt fromEucalyptus §Eucalyptus as plantation species.[edit]
In the 20th century, scientists around the world experimented withEucalyptus species. They hoped to grow them in the tropics, but most experimental results failed until breakthroughs in the 1960s-1980s in species selection, silviculture, and breeding programs "unlocked" the potential of eucalypts in the tropics. Prior to then, as Brett Bennett noted in a 2010 article, eucalypts were something of the "El Dorado" of forestry. Today,Eucalyptus is the most widely planted type of tree in plantations around the world,[7] inSouth America (mainly inBrazil,Argentina,Paraguay andUruguay),South Africa,Australia,India,Galicia,Portugal and many more.[8]

Teak

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This section is an excerpt fromPlantation teak.[edit]
Teak tree plantation
Plantation teak is a tropical hardwood tree from the genusTectona, endemic to Southeast Asia that is exclusively planted for the purpose of forestry management, for either commercial timber plantations orecological restoration. Although the genus Tectona is native to the tropical regions of Southeast Asia, primarilyIndonesia,Myanmar,India,Bangladesh andThailand, the cultivation of plantation teak is economically viable in other tropical regions such as Central America.

Christmas tree farms

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This section is an excerpt fromChristmas tree cultivation.[edit]
A Christmas tree farmer in theU.S. state ofFlorida explains the pruning and shearing process of cultivation to a government employee.

Christmas tree cultivation is anagricultural,forestry, andhorticultural occupation which involves growingpine,spruce, andfir trees specifically for use asChristmas trees.

The first Christmastree farm was established in 1901, but most consumers continued to obtain their trees from forests until the 1930s and 1940s. Christmas tree farming was once seen only as a viable alternative for low-quality farmland, but that perception has changed within the agriculture industry. For optimum yield and quality, land should be flat or gently rolling and relatively free of debris and undergrowth.

A wide variety of pine and fir species are grown as Christmas trees, although a handful of varieties stand out in popularity. In the United States,Douglas-fir,Scots pine andFraser fir all sell well.Nordmann fir andNorway spruce sell well in theUnited Kingdom, the latter being popular throughout Europe. Like allconifers, Christmas trees are vulnerable to a range ofpests.

The final stage of cultivation,harvesting, is carried out in a number of ways; one of the more popular methods is the pick-your-own tree farm, where customers are allowed to roam the farm, select their tree, and cut it down themselves. Other farmers cultivate potted trees, with balled roots, which can be replanted after Christmas and used again the following year.

Role in climate change mitigation

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See also:Carbon sequestration § Forestry,Deforestation and climate change,Reforestation, andTree planting § Role in climate change mitigation

A forest sequesters carbon in its trees. The forest removes carbon dioxide from the air as trees grow and returns it to the air as trees die and rot or burn. As long as the forest is experiencing net growth, the forest is reducing the amount of carbon dioxide, the leading greenhouse gas, from the air. Furthermore, if timber is regularly removed from the forest and turned into lasting wood products, those products continue sequestering carbon, while the replacement tree farm trees absorb more carbon dioxide, thus effecting a continuous reduction in greenhouse gas.[9][clarification needed] The fact that managed woodlands tend to be younger and younger trees grow faster and die less contributes to this distinction.[10]

While tree farms absorb large amounts of CO2, the long-termsequestration of this carbon depends on what is done with the harvested materials. Forests continue to absorb atmospheric carbon for centuries if left undisturbed.[11]

A variety of analytical tools are used to quantify the carbon sequestration in forest, varying considerably in their detail and intended purpose.[12]

Natural forest loss

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Many forestry experts claim that the establishment of plantations will reduce or eliminate the need to exploit natural forest for wood production. In principle this is true because due to the high productivity of plantations less land is needed. Many point to the example of New Zealand, where 19% of the forest area provides 99% of the supply of industrial round wood. It has been estimated that the world's demand for fiber could be met by just 5% of the world forest (Sedjo & Botkin 1997). However, in practice, plantations are replacing natural forest, for example in Indonesia. According to theFAO, about 7% of the natural closed forest being lost in the tropics is land being converted to plantations. The remaining 93% of the loss is land being converted to agriculture and other uses. Worldwide, an estimated 15% of plantations in tropical countries are established on closed canopy natural forest.

In theKyoto Protocol, there are proposals encouraging the use of plantations to reducecarbon dioxide levels (though this idea is being challenged by some groups on the grounds that the sequestered CO2 is eventually released after harvest).

A tea plantation in Ciwidey,Bandung inIndonesia

Ownership

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Main article:Wood industry

As of 2019, an estimated 49% offorests in the United States are owned by families.[13]

Notable corporations include Greenwood Resources, which is owned by TIAA-CREF.[14]

Problems

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Monocultures

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See also:Monoculture § Forestry

In contrast to a naturally regenerated forest, plantations are typically grown as even-agedmonocultures, primarily fortimber production. Plantations are always young forests in ecological terms. Typically, trees grown in plantations are harvested after 10 to 60 years, rarely up to 120 years. This means that the forests produced by plantations do not contain the type of growth, soil or wildlife typical ofold-growth natural forestecosystems. Most conspicuous is the absence of decaying dead wood, a crucial component of natural forest ecosystems.

Plantations are usually near- or total monocultures. That is, the same species of tree is planted across a given area, whereas a natural forest would contain a far more diverse range of tree species.

In the 1970s,Brazil began to establish high-yield, intensively managed, short rotation plantations. These types of plantations are sometimes called fast-wood plantations or fiber farms and often managed on a short-rotation basis, as little as 5 to 15 years. They are becoming more widespread in South America, Asia and other areas. The environmental and social impacts of this type of plantation has caused them to become controversial. InIndonesia, for example, large multi-national pulp companies have harvested large areas of natural forest without regard for regeneration. From 1980 to 2000, about 50% of the 1.4 million hectares of pulpwood plantations in Indonesia have been established on what was formerly naturalforest land.

Social problems

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The replacement of natural forest with tree plantations has also caused social problems. In some countries—again, notably Indonesia—conversions of natural forest are made with little regard for rights of the local people. Plantations established purely for the production of fiber provide a much narrower range of services than the original natural forest for the local people.India has sought to limit this damage by limiting the amount of land owned by one entity and, as a result, smaller plantations are owned by local farmers who then sell the wood to larger companies. Some large environmental organizations are critical of these high-yield plantations and are running an anti-plantation campaign, notably theRainforest Action Network andGreenpeace.

Introduced species

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In South America, Oceania, and East and Southern Africa, planted forests are dominated by introduced species: 88%, 75% and 65%, respectively. In North America, West and Central Asia, and Europe the proportions of introduced species in plantations are much lower at 1%, 3% and 8% of the total area planted, respectively.[15]

Plantations may include tree species that would not naturally occur in the area. They may include unconventional types such as hybrids, andgenetically modified trees may be used sometime in the future.[16][clarification needed] Since the primary interest in plantations is to producewood orpulp, the types of trees found in plantations are those that are best-suited to industrial applications. For example,pine,spruce andeucalyptus are widely planted far beyond their natural range because of their fast growth rate, tolerance of rich or degraded agricultural land and potential to produce large volumes of raw material for industrial use.

See also

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References

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  1. ^Aldhous, J. R.; Low, A. J. (1974).The potential of Western hemlock, Western red cedar, Grand fir and Noblefir in Britain(PDF) (Report). London: H.M. Stationery Office.
  2. ^Everard, J.E.; Fourt, D.F. (1974). "Monterey Pine and Bishop Pine as plantation trees in southern Britain".Quarterly Journal of Forestry.68 (2).Royal Forestry Society:111–125.
  3. ^"Forest loss".United Nations System-wide Earthwatch. United Nations Environment Programme. Archived fromthe original on January 6, 2010. RetrievedOctober 27, 2011.
  4. ^"Global Forest Resource Assessment 2020".www.fao.org. Retrieved20 September 2020.
  5. ^Wills, Matthew (2018-08-23)."How Eucalyptus Trees Stoke Wildfires".JSTOR Daily. Retrieved2022-04-23.
  6. ^Brown, Marjie (July 2009)."In Plantations or Natural Stands: Ponderosa Is Programmed to Partner with Fire"(PDF).Fire Science Brief (56).
  7. ^Bennett (2010)
  8. ^"Global Eucalyptus Map 2009... in Buenos Aires!".GIT Forestry Eucalyptologics. Retrieved22 November 2013.
  9. ^Bowyer, Jim (2011-10-11)."Managing Forests for Carbon Mitigation"(PDF). Dovetail Partners. Archived fromthe original(PDF) on 2012-04-03. Retrieved2024-02-10.
  10. ^McKinley, Duncan C.; et al. (2011)."A synthesis of current knowledge on forests and carbon storage in the United States"(PDF).Ecological Applications.21 (6):1902–1924.Bibcode:2011EcoAp..21.1902M.doi:10.1890/10-0697.1.PMID 21939033. Retrieved9 March 2013.
  11. ^Luyssaert, Sebastiaan; -Detlef Schulze, E.; Börner, Annett; Knohl, Alexander; Hessenmöller, Dominik; Law, Beverly E.; Ciais, Philippe; Grace, John (11 September 2008)."Old-growth forests as global carbon sinks"(PDF).Nature.455 (7210):213–215.Bibcode:2008Natur.455..213L.doi:10.1038/nature07276.PMID 18784722.S2CID 4424430.
  12. ^Zald, Harold S.J; Spies, Thomas A.; Harmon, Mark E.; Twery, Mark J. (2016)."Forest carbon calculators: a review for managers, policymakers, and educators"(PDF).Journal of Forestry.114 (2):134–143.doi:10.5849/jof.15-019.
  13. ^"Family Forest Owners: The Critical Link to Forest Resources".
  14. ^"Portland's GreenWood Resources nears $1B in timber assets".www.bizjournals.com. Retrieved2019-09-02.
  15. ^Payn, T. et al. 2015. Changes in planted forests and future global implications, Forest Ecology and Management 352: 57–67
  16. ^Overbeek W. (2012)."An overview of industrial tree plantation conflicts in the global South. Conflicts, trends, and resistance struggles"(PDF).EJOLT.3: 84.

External links

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