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103-579: Pseudotsuga menziesii var. menziesii , commonly known as Coast Douglas-fir , Pacific Douglas-fir , Oregon pine , or Douglas spruce , is an evergreen conifer native to western North America from west-central British Columbia , Canada southward to central California , United States . In Oregon and Washington its range is continuous from the Cascades crest west to the Pacific Coast Ranges and Pacific Ocean . In California, it

206-570: A Latinate word denoting a woodland, may be admitted; in a specific technical sense it is restricted to denoting the species of trees that comprise the woodlands of a region, as in its sense in the subject of silviculture . The resorting to sylva in English indicates more precisely the denotation that the use of forest intends. The first known forests on Earth arose in the Middle Devonian (approximately 390 million years ago ), with

309-738: A Douglas-fir seed crop following dispersal in western Oregon. The Douglas squirrel ( Tamiasciurus douglasii ) harvests and caches great quantities of Douglas-fir cones for later use. They also eat mature pollen cones, developing inner bark, terminal shoots, and tender young needles. The seeds are also important in the diets of several seed-eating birds. These include most importantly American sparrows (Emberizidae) – dark-eyed junco ( Junco hyemalis ), song sparrow ( Melospiza melodia ), golden-crowned sparrow ( Zonotrichia atricapilla ) and white-crowned sparrow ( Z. leucophrys ) – and true finches (Fringillidae) – pine siskin ( Carduelis pinus ), purple finch ( "Carpodacus" purpureus ), and

412-464: A clear-cut area with Douglas-fir seedlings. The high-light conditions that exist within a clear-cut also naturally favor the regeneration of Douglas-fir, though in wet coastal climates alders and shrubs compete with Douglas-fir seedlings. Because of clear-cut logging, almost all of the forests west of the Cascade Range not strictly set aside for protection are today dominated by Douglas-fir, while

515-497: A cold or dry/wet season. Evergreen trees also lose leaves, but each tree loses its leaves gradually and not all at once. Most tropical rainforest plants are considered to be evergreens, replacing their leaves gradually throughout the year as the leaves age and fall, whereas species growing in seasonally arid climates may be either evergreen or deciduous. Most warm temperate climate plants are also evergreen. In cool temperate climates, fewer plants are evergreen. In such climates, there

618-464: A combination of measures aimed at increasing forest carbon stocks, andsustainable timber offtake will generate the largest carbon sequestration benefit. The term forest-dependent people is used to describe any of a wide variety of livelihoods that are dependent on access to forests, products harvested from forests, or ecosystem services provided by forests, including those of Indigenous peoples dependent on forests. In India , approximately 22 percent of

721-405: A different classification of forest vegetation is often used: tree, shrub, herb, and moss layers (see stratification (vegetation) ). Forests are classified differently and to different degrees of specificity. One such classification is in terms of the biomes in which they exist, combined with leaf longevity of the dominant species (whether they are evergreen or deciduous ). Another distinction

824-603: A faster growth rate than most other trees, giving the Douglas-fir a competitive advantage when it overtops slower growing species during re-establishment of the canopy. The tree ring ages of dominant Douglas-fir trees can indicate the date of the last stand-replacing fire. Because Douglas-fir is long-lived, it can remain dominant in the forest for more than 300-years following the last fire. A history of fluctuating climate resulted in synchronous fire episodes across western Washington and Oregon, thus many Douglas-fir stands date to

927-437: A few main pathways, including increase in commercial tree plantations, adoption of agroforestry techniques by small farmers, or spontaneous regeneration when former agricultural land is abandoned. It can be motivated by the economic benefits of forests, the ecosystem services forests provide, or cultural changes where people increasingly appreciate forests for their spiritual, aesthetic, or otherwise intrinsic value. According to

1030-511: A forest as, "Land spanning more than 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10 percent, or trees able to reach these thresholds in situ . It does not include land that is predominantly under agricultural or urban use." Using this definition, Global Forest Resources Assessment 2020 found that forests covered 4.06 billion hectares (10.0 billion acres; 40.6 million square kilometres; 15.7 million square miles), or approximately 31 percent of

1133-409: A forest may be of a great variety of species (as in tropical rainforests and temperate deciduous forests ), or relatively few species over large areas (e.g., taiga and arid montane coniferous forests). The biodiversity of forests also encompasses shrubs , herbaceous plants, mosses , ferns , lichens , fungi , and a variety of animals . Trees rising up to 35 meters (115 ft) in height add

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1236-550: A forested area by cutting or burning, either to harvest timber or to make way for farming. Most deforestation today occurs in tropical forests. The vast majority of this deforestation is because of the production of four commodities: wood , beef , soy , and palm oil . Over the past 2,000 years, the area of land covered by forest in Europe has been reduced from 80% to 34%. Large areas of forest have also been cleared in China and in

1339-731: A higher soil acidity and lower soil nitrogen content. This is the case with Mediterranean evergreen seedlings, which have unique C and N storages that allow stored resources to determine fast growth within the species, limiting competition and bolstering survival. These conditions favor the growth of more evergreens and make it more difficult for deciduous plants to persist. In addition, the shelter provided by existing evergreen plants can make it easier for younger evergreen plants to survive cold and/or drought. Evergreen plants can have decorative as well as functional uses. In months where most other plants are dormant, evergreens with their sturdy structure, and vibrant foliage are popular choices to beautify

1442-519: A landscape. Additionally, evergreens can serve as a windbreak , stopping heat loss from buildings during cold months when placed on the northwest side of a structure. Forest A forest is an ecosystem characterized by a dense community of trees . Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' Food and Agriculture Organization (FAO) defines

1545-420: A larger volume of parenchyma and air spaces per unit leaf area. They have larger leaf biomass per unit leaf area, and hence a lower specific leaf area . Construction costs do not differ between the groups. Evergreens have generally a larger fraction of total plant biomass present as leaves (LMF), but they often have a lower rate of photosynthesis. Deciduous trees shed their leaves usually as an adaptation to

1648-452: A legal term, as seen in Latin texts such as Magna Carta , to denote uncultivated land that was legally designated for hunting by feudal nobility (see royal forest ). These hunting forests did not necessarily contain any trees. Because that often included significant areas of woodland, "forest" eventually came to connote woodland in general, regardless of tree density. By the beginning of

1751-403: A locale with more open space between trees, and distinguish kinds of woodlands as open forests and closed forests , premised on their crown covers . Finally, sylva (plural sylvae or, less classically, sylvas ) is a peculiar English spelling of the Latin silva , denoting a "woodland", and has precedent in English, including its plural forms. While its use as a synonym of forest , and as

1854-486: A minor component. Coast Douglas-fir is one of the world's best timber producers and yields more timber than any other tree in North America. The wood is used for dimensional lumber , timbers, pilings, and plywood . Creosote treated pilings and decking are used in marine structures. The wood is also made into railroad ties, mine timbers, house logs, posts and poles, flooring, pulp, and furniture. Coast Douglas-fir

1957-508: A narrow, cylindric crown beginning 20–40 metres (66–131 ft) above a branch-free trunk. Self-pruning is generally slow and trees retain their lower limbs for a long period. Young, open-grown trees typically have branches down to near ground level. It often takes 70–80 years for the trunk to be clear to a height of 5 metres (16 ft) and 100 years to be clear to a height of 10 metres (33 ft). Appreciable seed production begins at 20–30 years in open-grown coast Douglas-fir. Seed production

2060-583: A region, releasing water from their leaves in anticipation of seasonal rains to trigger the wet season early. Because of this, seasonal rainfall in the Amazon begins two to three months earlier than the climate would otherwise allow. Deforestation in the Amazon and anthropogenic climate change hold the potential to interfere with this process, causing the forest to pass a threshold where it transitions into savanna. Deforestation threatens many forest ecosystems. Deforestation occurs when humans remove trees from

2163-722: A vertical dimension to the area of land that can support plant and animal species, opening up numerous ecological niches for arboreal animal species, epiphytes , and various species that thrive under the regulated microclimate created under the canopy. Forests have intricate three-dimensional structures that increase in complexity with lower levels of disturbance and greater variety of tree species. The biodiversity of forests varies considerably according to factors such as forest type, geography, climate, and soils – in addition to human use. Most forest habitats in temperate regions support relatively few animal and plant species, and species that tend to have large geographical distributions, while

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2266-401: A very distinctive narrow conic shape, 4–8 mm ( 3 ⁄ 16 – 5 ⁄ 16  in) long, with red-brown bud scales. The leaves are spirally arranged but slightly twisted at the base to lie in flattish either side of the shoot, needle-like, 2–3.5 cm ( 3 ⁄ 4 – 1 + 3 ⁄ 8  in) long, green above with no stomata , and with two whitish stomatal bands below. Unlike

2369-446: A warm-dry periods in the late 1400s and early 1500s, while few date to a cool-wet period from 1650 to 1800. Douglas-fir is also particularly well adapted to fires: once they reach around 100 years in age they have thick enough bark that protects the cambium layer of the tree from heat damage. Large Douglas-fir often survive low intensity forest fires. Such sites, common in western Oregon, have two or three cohorts of Douglas-fir, adding to

2472-412: A wide range of characteristics. Generally, richer households derive more cash value from forest resources, whereas among poorer households, forest resources are more important for home consumption and increase community resilience. Forests are fundamental to the culture and livelihood of indigenous people groups that live in and depend on forests, many of which have been removed from and denied access to

2575-438: Is a predominance of conifers because few evergreen broadleaf plants can tolerate severe cold below about −26 °C (−15 °F). In addition, evergreen foliage experiences significant leaf damage in these cold, dry climates. Root systems are the most vulnerable aspect of many plants. Even though roots are insulated by soil, which tends to be warmer than average air temperatures, soil temperatures that drop too low can kill

2678-401: Is based on tree densities measured on over 400,000 plots. It remains subject to a wide margin of error, not least because the samples are mainly from Europe and North America. Forests can also be classified according to the amount of human alteration. Old-growth forest contains mainly natural patterns of biodiversity in established seral patterns, and they contain mainly species native to

2781-631: Is covered by epiphytic mosses and lichens . The shade-intolerance of Douglas-fir plays a large role in the forest succession of lowland old-growth forest communities of the Pacific Northwest. While mature stands of lowland old-growth forest contain many western hemlock ( Tsuga heterophylla ) seedlings, and some western redcedar ( Thuja plicata ) seedlings, Douglas-fir dominated stands contain almost no Douglas-fir seedlings. This seeming contradiction occurs because Douglas-firs are intolerant of deep shade and rarely survive for long within

2884-918: Is found in the Klamath and California Coast Ranges as far south as the Santa Lucia Mountains with a small stand as far south as the Purisima Hills , Santa Barbara County . In the Sierra Nevada it ranges as far south as the Yosemite region. It occurs from near sea level along the coast to 1,800 metres (5,900 ft) in the California Mountains. Further inland, coast Douglas-fir is replaced by Rocky Mountain or interior Douglas-fir ( P. menziesii var. glauca ). Interior Douglas-fir intergrades with coast Douglas-fir in

2987-630: Is high compared to other vegetation communities. Much of this biomass occurs below ground in the root systems and as partially decomposed plant detritus . The woody component of a forest contains lignin , which is relatively slow to decompose compared with other organic materials such as cellulose or carbohydrate. The world's forests contain about 606 gigatonnes of living biomass (above- and below-ground) and 59 gigatonnes of dead wood. The total biomass has decreased slightly since 1990, but biomass per unit area has increased. Forest ecosystems broadly differ based on climate ; latitudes 10° north and south of

3090-403: Is irregular; over a 5-7 year period, stands usually produce one heavy crop, a few light or medium crops, and one crop failure. Even during heavy seed crop years, only about 25 percent of trees in closed stands produce an appreciable number of cones. Each cone contains around 25 to 50 seeds. Seed size varies; average number of cleaned seeds varies from 70 to 88/g (32,000-40,000 per pound). Seeds from

3193-543: Is not on track to meet the target of the United Nations Strategic Plan for Forests to increase forest area by 3 percent by 2030. While deforestation is taking place in some areas, new forests are being established through natural expansion or deliberate efforts in other areas. As a result, the net loss of forest area is less than the rate of deforestation; and it, too, is decreasing: from 7.8 million hectares (19 million acres) per year in

Pseudotsuga menziesii var. menziesii - Misplaced Pages Continue

3296-428: Is that forests can turn from a carbon sink to a carbon source if plant diversity, density or forest area decreases, as has been observed in different tropical forests The typical tropical forest may become a carbon source by the 2060s. An assessment of European forests found early signs of carbon sink saturation, after decades of increasing strength. The Intergovernmental Panel on Climate Change (IPCC) concluded that

3399-771: Is the Doerner Fir , (previously known as the Brummit fir), 99.76 m (327 ft 4 in) tall, at East Fork Brummit Creek in Coos County, Oregon , the stoutest is the Queets Fir , 4.85 m (15 ft 11 in) diameter, in the Queets River valley, Olympic National Park , Washington. The tallest specimen ever was probably the Nooksack Giant , with a height of 142 metres as measured by tape after

3502-771: Is the "Doerner Fir", previously known as the Brummit Fir, 99.8 m (327.3 ft) tall, at East Fork Brummit Creek in Coos County, Oregon , the stoutest is the "Queets Fir", 4.85 m (15 ft 11 in) in diameter, in the Queets River valley of Olympic National Park in Washington. The largest at 349 cubic metres (12,300 cu ft) is the Red Creek fir in British Columbia, Canada. Douglas firs commonly live more than 500 years and occasionally more than 1,000 years. The tallest well-documented conifer

3605-470: Is the primary habitat of the red tree vole ( Arborimus longicaudus ) and the spotted owl ( Strix occidentalis ). Home range requirements for breeding pairs of spotted owls are at least 400 ha (4 square kilometres (990 acres) of old-growth. Red tree voles may also be found in immature forests if Douglas-fir is a significant component. This animal nests almost exclusively in the foliage of Douglas-fir trees. Nests are located 2–50 metres (6.6–164.0 ft) above

3708-550: Is used extensively in landscaping. It is planted as a specimen tree or in mass screenings. It is also a popular Christmas tree . As of 1995, coast Douglas fir was the second-tallest conifer in the world (after coast redwood ). Extant coast Douglas fir trees 60–75 m (195–245 ft) or more in height and 1.5–2 m (4.9–6.6 ft) in diameter are common in old growth stands, and maximum heights of 100–120 m (330–395 ft) and diameters up to 4.5–5.5 m (15–18 ft) have been documented. The tallest living specimen

3811-416: Is whether the forests are composed predominantly of broadleaf trees, coniferous (needle-leaved) trees, or mixed. The number of trees in the world, according to a 2015 estimate, is 3 trillion, of which 1.4 trillion are in the tropics or sub-tropics, 0.6 trillion in the temperate zones, and 0.7 trillion in the coniferous boreal forests. The 2015 estimate is about eight times higher than previous estimates, and

3914-606: The Equator , and temperate forests at the middle latitudes . Forests form in areas of the Earth with high rainfall, while drier conditions produce a transition to savanna . However, in areas with intermediate rainfall levels, forest transitions to savanna rapidly when the percentage of land that is covered by trees drops below 40 to 45 percent. Research conducted in the Amazon rainforest shows that trees can alter rainfall rates across

4017-651: The Medieval Latin foresta , denoting "open wood", Carolingian scribes first used foresta in the capitularies of Charlemagne , specifically to denote the royal hunting grounds of the king. The word was not endemic to the Romance languages , e.g., native words for forest in the Romance languages derived from the Latin silva , which denoted "forest" and " wood(land) " ( cf. the English sylva and sylvan ;

4120-592: The Proto-Germanic * furhísa- , * furhíþija- , denoting "a fir-wood , coniferous forest", from the Proto-Indo-European * perk u- , denoting "a coniferous or mountain forest , wooded height" all attest to the Frankish * forhist . Uses of forest in English to denote any uninhabited and unenclosed area are presently considered archaic. The Norman rulers of England introduced the word as

4223-554: The Special Report on Global Warming of 1.5 °C of the Intergovernmental Panel on Climate Change , to avoid temperature rise by more than 1.5 degrees above pre-industrial levels, there will need to be an increase in global forest cover equal to the land area of Canada (10 million square kilometres (3.9 million square miles)) by 2050. China instituted a ban on logging, beginning in 1998, due to

Pseudotsuga menziesii var. menziesii - Misplaced Pages Continue

4326-895: The Umpqua River in Oregon. Shrub associates in the central and northern part of Coast Douglas-fir's range include vine maple ( Acer circinatum ), salal ( Gaultheria shallon ), Pacific rhododendron ( Rhododendron macrophyllum ), Oregon-grape ( Mahonia aquifolium ), red huckleberry ( Vaccinium parvifolium ), and salmonberry ( Rubus spectabilis ). In the drier, southern portion of its range shrub associates include California hazel ( Corylus cornuta var. californica ), oceanspray ( Holodiscus discolor ), creeping snowberry ( Symphoricarpos mollis ), western poison-oak ( Toxicodendron diversilobum ), ceanothus ( Ceanothus spp.), and manzanita ( Arctostaphylos spp.). In wet coastal forests, nearly every surface of old-growth coast Douglas-fir

4429-561: The United Kingdom is a coast Douglas-fir. The tree, growing near Ardentinny in Scotland stands at 68.4 m (224 ft). Why do you not list any papers by Suzanne Simard from her 50 years of research on Douglas fir? Evergreen There are many different kinds of evergreen plants, including trees , shrubs , and vines. Evergreens include: The Latin binomial term sempervirens , meaning "always green", refers to

4532-592: The World Resources Institute recorded that only 20% of the world's original forests remained in large intact tracts of undisturbed forest. More than 75% of these intact forests lie in three countries: the boreal forests of Russia and Canada, and the rainforest of Brazil. According to Food and Agriculture Organization 's (FAO) Global Forest Resources Assessment 2020 , an estimated 420 million hectares (1.0 billion acres) of forest have been lost worldwide through deforestation since 1990, but

4635-418: The boreal region and in the seasonally dry tropics. At high latitudes, north of the main zone of boreal forestland, growing conditions are not adequate to maintain a continuously closed forest cover , so tree cover is both sparse and discontinuous. This vegetation is variously called open taiga , open lichen woodland, and forest tundra. A savanna is a mixed woodland – grassland ecosystem characterized by

4738-407: The equator are mostly covered in tropical rainforest , and the latitudes between 53°N and 67°N have boreal forest . As a general rule, forests dominated by angiosperms ( broadleaf forests ) are more species-rich than those dominated by gymnosperms ( conifer , montane , or needleleaf forests ), although exceptions exist. The trees that form the principal structural and defining component of

4841-408: The slash and burn practices of swidden agriculture or shifting cultivation . The loss and re-growth of forests lead to a distinction between two broad types of forest: primary or old-growth forest and secondary forest . There are also many natural factors that can cause changes in forests over time, including forest fires , insects , diseases , weather, competition between species, etc. In 1997,

4944-429: The 1990s to 4.7 million hectares (12 million acres) per year during 2010–2020. In absolute terms, the global forest area decreased by 178 million hectares (440 million acres; 1,780,000 square kilometres; 690,000 square miles) between 1990 and 2020, which is an area about the size of Libya. Forests provide a diversity of ecosystem services including: The main ecosystem services can be summarized in

5047-521: The 1990s. In 2015, a study for Nature Climate Change showed that the trend has recently been reversed, leading to an "overall gain" in global biomass and forests. This gain is due especially to reforestation in China and Russia. New forests are not equivalent to old growth forests in terms of species diversity, resilience, and carbon capture. On 7 September 2015, the FAO released a new study stating that over

5150-603: The Cascades of northern Washington and southern British Columbia . Coast Douglas-fir is the second-tallest conifer in the world (after coast redwood ), and the third-tallest of all trees, (after Eucalyptus regnans ). Currently, coast Douglas-fir trees 60–75 metres (197–246 ft) or more in height and 1.5–2 metres (4.9–6.6 ft) in diameter are common in old growth stands, and maximum heights of 100–120 metres (330–390 ft) and diameters up to 4.5–5.5 metres (15–18 ft) have been documented. The tallest living specimen

5253-875: The Douglas-fir red crossbill ( Loxia curvirostra neogaea ) which is uniquely adapted to foraging for P. menziesii seeds. The coast Douglas-fir variety is the dominant tree west of the Cascade Mountains in the Pacific Northwest , occurring in nearly all forest types, competes well on most parent materials, aspects, and slopes. Adapted to a moist, mild climate, it grows larger and faster than Rocky Mountain Douglas-fir . Associated trees include western hemlock , Sitka spruce , sugar pine , western white pine , Ponderosa pine , grand fir , coast redwood , western redcedar , California incense-cedar , Lawson's cypress , tanoak , bigleaf maple and several others. Pure stands are also common, particularly north of

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5356-459: The Earth's plant biomass . Net primary production is estimated at 21.9 gigatonnes of biomass per year for tropical forests , 8.1 for temperate forests , and 2.6 for boreal forests . Forests form distinctly different biomes at different latitudes and elevations, and with different precipitation and evapotranspiration rates. These biomes include boreal forests in subarctic climates, tropical moist forests and tropical dry forests around

5459-725: The Italian, Spanish, and Portuguese selva ; the Romanian silvă ; the Old French selve ). Cognates of forest in Romance languages—e.g., the Italian foresta , Spanish and Portuguese floresta , etc.—are all ultimately derivations of the French word. The precise origin of Medieval Latin foresta is obscure. Some authorities claim the word derives from the Late Latin phrase forestam silvam , denoting "the outer wood"; others claim

5562-517: The Rocky Mountain Douglas-fir, coast Douglas-fir foliage has a noticeable sweet fruity-resinous scent, particularly if crushed. The mature female seed cones are pendent, 5–8 cm (2– 3 + 1 ⁄ 4  in) long, 2–3 cm ( 3 ⁄ 4 – 1 + 1 ⁄ 4  in) broad when closed, opening to 4 cm ( 1 + 1 ⁄ 2  in) broad. They are produced in spring, green at first, maturing orange-brown in

5665-452: The U.S. state of Wisconsin , forests managed by indigenous people have more plant diversity, fewer invasive species, higher tree regeneration rates, and higher volume of trees. Forest management has changed considerably over the last few centuries, with rapid changes from the 1980s onward, culminating in a practice now referred to as sustainable forest management . Forest ecologists concentrate on forest patterns and processes, usually with

5768-460: The aim of elucidating cause-and-effect relationships. Foresters who practice sustainable forest management focus on the integration of ecological, social, and economic values, often in consultation with local communities and other stakeholders . Humans have generally decreased the amount of forest worldwide. Anthropogenic factors that can affect forests include logging, urban sprawl , human-caused forest fires , acid rain , invasive species , and

5871-448: The annual mortality of large Douglas-fir is only about 1%. Thus, over centuries, western hemlock and western redcedar will come to dominate the canopy . Douglas-fir is a seral species in the wet forests of western British Columbia, Washington, Oregon, and California. In these areas, it requires a large disturbance, such as fire or a large landslide, to open the forest and expose mineral soil where its seedlings prefer to establish. It has

5974-476: The area in which they reside. The excellent water economy within the evergreen species is due to high abundance when compared to deciduous species. Whereas deciduous trees lose nutrients whenever they lose their leaves. In warmer areas, species such as some pines and cypresses grow on poor soils and disturbed ground. In Rhododendron , a genus with many broadleaf evergreens, several species grow in mature forests but are usually found on highly acidic soil where

6077-432: The autumn 6–7 months later. The seeds are 5–6 mm ( 3 ⁄ 16 – 1 ⁄ 4  in) long and 3–4 mm ( 1 ⁄ 8 – 3 ⁄ 16  in) broad, with a 12–15 mm ( 1 ⁄ 2 – 9 ⁄ 16  in) wing. The male ( pollen ) cones are 2–3 cm ( 3 ⁄ 4 – 1 + 1 ⁄ 4  in) long, dispersing yellow pollen in spring. In forest conditions, old individuals typically have

6180-420: The basis of the variation of physiognomy corresponding to changes in altitude. Tropical dry forests are characteristic of areas in the tropics affected by seasonal drought. The seasonality of rainfall is usually reflected in the deciduousness of the forest canopy, with most trees being leafless for several months of the year. Under some conditions, such as less fertile soils or less predictable drought regimes,

6283-590: The canopy; but other taxa are also important. In the Southern Hemisphere , most coniferous trees (members of Araucariaceae and Podocarpaceae ) occur mixed with broadleaf species, and are classed as broadleaf-and-mixed forests. Temperate broadleaf and mixed forests include a substantial component of trees of the Anthophyta group. They are generally characteristic of the warmer temperate latitudes, but extend to cool temperate ones, particularly in

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6386-423: The children live. Canada has about 4 million square kilometres (1.5 million square miles) of forest land. More than 90% of forest land is publicly owned and about 50% of the total forest area is allocated for harvesting. These allocated areas are managed using the principles of sustainable forest management, which include extensive consultation with local stakeholders. About eight percent of Canada's forest

6489-419: The complexity of the old-growth forest. Fire is increasingly rare northward towards the central coast of British Columbia where Douglas-fir is a minor component of the forest. The logging practices of the last 200 years created artificial disturbances that allowed Douglas-fir to thrive. The Douglas-fir's useful wood and its quick growth make it the crop of choice for many timber companies, which typically replant

6592-517: The cutoff points are between a forest, woodland , and savanna . Under some definitions, to be considered a forest requires very high levels of tree canopy cover, from 60% to 100%, which excludes woodlands and savannas, which have a lower canopy cover . Other definitions consider savannas to be a type of forest, and include all areas with tree canopies over 10%. Some areas covered with trees are legally defined as agricultural areas, for example Norway spruce plantations, under Austrian forest law, when

6695-418: The density of trees, area of tree canopy cover, or area of the land occupied by the cross-section of tree trunks ( basal area ) meeting a particular threshold. This type of definition depends upon the presence of trees sufficient to meet the threshold, or at least of immature trees that are expected to meet the threshold once they mature. Under land-cover definitions, there is considerable variation on where

6798-411: The eastern United States , in which only 0.1% of land was left undisturbed. Almost half of Earth's forest area (49 percent) is relatively intact, while 9 percent is found in fragments with little or no connectivity. Tropical rainforests and boreal coniferous forests are the least fragmented, whereas subtropical dry forests and temperate oceanic forests are among the most fragmented. Roughly 80 percent of

6901-585: The erosion and flooding that it caused. In addition, ambitious tree-planting programmes in countries such as China, India, the United States, and Vietnam – combined with natural expansion of forests in some regions – have added more than 7 million hectares (17 million acres) of new forests annually. As a result, the net loss of forest area was reduced to 5.2 million hectares (13 million acres) per year between 2000 and 2010, down from 8.3 million hectares (21 million acres) annually in

7004-552: The evergreen nature of the plant, for instance: The longevity of individual leaves in evergreen plants varies from a few months to several decades (over 30 years in the Great Basin bristlecone pine ). Japanese umbrella pine is unique in that it has its own family of which it is the only species. Evergreen and deciduous species vary in a range of morphological and physiological characters. Generally, broad-leaved evergreen species have thicker leaves than deciduous species, with

7107-465: The evolution of cladoxylopsid plants like Calamophyton . Appeared in the Late Devonian , Archaeopteris was both tree-like and fern -like plant, growing to 20 metres (66 ft) in height or more. It quickly spread throughout the world, from the equator to subpolar latitudes. It is the first species known to cast shade due to its fronds and forming soil from its roots. Archaeopteris

7210-417: The forest ecosystem. Since 2002, the amount of land that is legally owned by or designated for indigenous peoples has broadly increased, but land acquisition in lower-income countries by multinational corporations, often with little or no consultation of indigenous peoples, has also increased. Research in the Amazon rainforest suggests that indigenous methods of agroforestry form reservoirs of biodiversity. In

7313-415: The fourteenth century, English texts used the word in all three of its senses: common, legal, and archaic. Other English words used to denote "an area with a high density of trees" are firth , frith , holt , weald , wold , wood , and woodland . Unlike forest , these are all derived from Old English and were not borrowed from another language. Some present classifications reserve woodland for denoting

7416-410: The ground. The red tree vole's diet consists chiefly of common Douglas-fir needles. A parasitic plant sometimes utilizing P. menziesii is Arceuthobium douglasii Commonly known as Douglas-fir dwarf mistletoe. Its seedlings are not a preferred browse of black-tailed deer ( Odocoileus hemionus columbianus ) and elk ( Cervus canadensis ), but can be an important food source for these animals during

7519-542: The higher latitudes of the Northern Hemisphere , as well as some warm temperate areas, especially on nutrient-poor or otherwise unfavourable soils. These forests are composed entirely, or nearly so, of coniferous species ( Coniferophyta ). In the Northern Hemisphere, pines Pinus , spruces Picea , larches Larix , firs Abies , Douglas firs Pseudotsuga , and hemlocks Tsuga make up

7622-469: The lands on which they lived as part of global colonialism . Indigenous lands contain 36% or more of intact forest worldwide, host more biodiversity, and experience less deforestation. Indigenous activists have argued that degradation of forests and indigenous peoples' marginalization and land dispossession are interconnected. Other concerns among indigenous peoples include lack of Indigenous involvement in forest management and loss of knowledge related for

7725-493: The last 25 years the global deforestation rate has decreased by 50% due to improved management of forests and greater government protection. There is an estimated 726 million hectares (1.79 billion acres) of forest in protected areas worldwide. Of the six major world regions, South America has the highest share of forests in protected areas, at 31 percent. The area of such areas globally has increased by 191 million hectares (470 million acres) since 1990, but

7828-991: The montane forests of Africa, South America, Southeast Asia, and lowland forests of Australia, coastal Brazil, the Caribbean islands, Central America, and insular Southeast Asia have many species with small geographical distributions. Areas with dense human populations and intense agricultural land use, such as Europe, parts of Bangladesh, China, India, and North America, are less intact in terms of their biodiversity. Northern Africa, southern Australia, coastal Brazil, Madagascar, and South Africa are also identified as areas with striking losses in biodiversity intactness. A forest consists of many components that can be broadly divided into two categories: biotic (living) and abiotic (non-living). The living parts include trees , shrubs , vines , grasses and other herbaceous (non-woody) plants, mosses , algae , fungi , insects , mammals , birds , reptiles , amphibians , and microorganisms living on

7931-530: The next table: Some researchers state that forests do not only provide benefits, but can in certain cases also incur costs to humans. Forests may impose an economic burden, diminish the enjoyment of natural areas, reduce the food-producing capacity of grazing land and cultivated land, reduce biodiversity, reduce available water for humans and wildlife, harbour dangerous or destructive wildlife, and act as reservoirs of human and livestock disease. An important consideration regarding carbon sequestration

8034-467: The normally dominant climax species, such as western hemlock and western redcedar are less common. On drier sites in California, where Douglas-fir behaves as a climax species in the absence of fire, Douglas-fir has become somewhat invasive following fire suppression practices of the twentieth and twenty-first centuries; it is becoming a dominant species in many oak woodlands , in which it was previously

8137-714: The northern portion of coast Douglas-fir's range tend to be larger than seed from the south. The rooting habit of coast Douglas-fir is not particularly deep, with the roots tending to be shallower than those of same-aged Ponderosa pine, sugar pine, or California incense-cedar, though deeper than Sitka spruce. Some roots are commonly found in organic soil layers or near the mineral soil surface. However, Douglas-fir exhibits considerable morphological plasticity, and on drier sites coast Douglas-fir will generate deeper taproots. Douglas-fir snags are abundant in forests older than 100–150 years and provide cavity-nesting habitat for numerous forest birds. Mature or "old-growth" Douglas-fir forest

8240-423: The nutrients are less available to plants. In taiga or boreal forests , it is too cold for the organic matter in the soil to decay rapidly, so the nutrients in the soil are less easily available to plants, thus favoring evergreens. In temperate climates, evergreens can reinforce their own survival; evergreen leaf and needle litter has a higher carbon-nitrogen ratio than deciduous leaf litter , contributing to

8343-448: The plant. The exact temperature which evergreen roots can handle depends on the species, for example, Picea Glauca (White Spruce) roots are killed at −10 °F (−23 °C). In areas where there is a reason for being deciduous, e.g. a cold season or dry season, evergreen plants are usually an adaptation of low nutrient levels. Additionally, they usually have hard leaves and have an excellent water economy due to scarce resources in

8446-411: The plants and animals and in the soil, connected by mycorrhizal networks . The main layers of all forest types are the forest floor , the understory, and the canopy. The emergent layer, above the canopy, exists in tropical rainforests. Each layer has a different set of plants and animals, depending upon the availability of sunlight, moisture, and food. In botany and countries like Germany and Poland,

8549-512: The population belongs to forest-dependent communities, which live in close proximity to forests and practice agroforestry as a principal part of their livelihood. People of Ghana who rely on timber and bushmeat harvested from forests and Indigenous peoples of the Amazon rainforest are also examples of forest-dependent people. Though forest-dependence by more common definitions is statistically associated with poverty and rural livelihoods, elements of forest-dependence exist in communities with

8652-615: The proportion of evergreen species increases and the forests are characterised as " sclerophyllous ". Thorn forest , a dense forest of low stature with a high frequency of thorny or spiny species, is found where drought is prolonged, and especially where grazing animals are plentiful. On very poor soils, and especially where fire or herbivory are recurrent phenomena, savannas develop. Sparse trees and savanna are forests with sparse tree- canopy cover. They occur principally in areas of transition from forested to non-forested landscapes. The two major zones in which these ecosystems occur are in

8755-428: The rate of forest loss has declined substantially. In the most recent five-year period (2015–2020), the annual rate of deforestation was estimated at 10 million hectares (25 million acres), down from 12 million hectares (30 million acres) annually in 2010–2015. The transition of a region from forest loss to net gain in forested land is referred to as the forest transition. This change occurs through

8858-465: The rate of annual increase slowed in 2010–2020. Smaller areas of woodland in cities may be managed as urban forestry , sometimes within public parks. These are often created for human benefits; Attention Restoration Theory argues that spending time in nature reduces stress and improves health, while forest schools and kindergartens help young people to develop social as well as scientific skills in forests. These typically need to be close to where

8961-460: The region and habitat. In contrast, secondary forest is forest regrowing following timber harvest and may contain species originally from other regions or habitats. Different global forest classification systems have been proposed, but none has gained universal acceptance. UNEP - WCMC 's forest category classification system is a simplification of other, more complex systems (e.g. UNESCO 's forest and woodland 'subformations'). This system divides

9064-477: The shaded understory. When a tree dies in a mature forest the canopy opens up and sunlight becomes available as a source of energy for new growth. The shade-tolerant western hemlock and western redcedar seedlings that establish beneath the canopy have a head-start on other seedlings. This competitive advantage allows western hemlock to rapidly fill the canopy gap, pre-empting other species that may invade, including Douglas-fir. Long-term forest dynamics plots show that

9167-616: The southern hemisphere. They include such forest types as the mixed deciduous forests of the United States and their counterparts in China and Japan; the broadleaf evergreen rainforests of Japan, Chile , and Tasmania ; the sclerophyllous forests of Australia, central Chile, the Mediterranean , and California; and the southern beech Nothofagus forests of Chile and New Zealand. There are many different types of tropical moist forests , with lowland evergreen broad-leaf tropical rainforests : for example várzea and igapó forests and

9270-690: The terra firme forests of the Amazon Basin ; the peat swamp forests ; dipterocarp forests of Southeast Asia ; and the high forests of the Congo Basin . Seasonal tropical forests , perhaps the best description for the colloquial term " jungle ", typically range from the rainforest zone 10 degrees north or south of the equator , to the Tropic of Cancer and Tropic of Capricorn . Forests located on mountains are also included in this category, divided largely into upper and lower montane formations, on

9373-415: The tree was cut down. Coast Douglas-fir commonly lives more than 500 years and occasionally more than 1,000 years. The bark on young trees is thin, smooth, gray, and contains numerous resin blisters. On mature trees, it is thick and corky. The shoots are brown to olive-green, turning gray-brown with age, smooth, though not as smooth as fir shoots, and finely pubescent with short dark hairs. The buds are

9476-476: The trees are being grown as Christmas trees and are below a certain height. The word forest derives from the Old French forest (also forès ), denoting "forest, vast expanse covered by trees"; forest was first introduced into English as the word denoting wild land set aside for hunting without necessarily having trees on the land. Possibly a borrowing, probably via Frankish or Old High German , of

9579-425: The trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer that consists primarily of grasses. Savannas maintain an open canopy despite a high tree density. Forest plantations are generally intended for the production of timber and pulpwood . Commonly mono-specific, planted with even spacing between

9682-403: The trees, and intensively managed, these forests are generally important as habitat for native biodiversity . Some are managed in ways that enhance their biodiversity protection functions and can provide ecosystem services such as nutrient capital maintenance, watershed and soil structure protection and carbon storage. The annual net loss of forest area has decreased since 1990, but the world

9785-505: The type of vegetation that grows upon the land; an area can be legally designated "forest" even if no trees grow on it. Land-use definitions are based on the primary purpose the land is used for. Under a land-use definition, any area used primarily for harvesting timber, including areas that have been cleared by harvesting, disease, fire, or for the construction of roads and infrastructure, are still defined as forests, even if they contain no trees. Land-cover definitions define forests based upon

9888-424: The winter when other preferred forages are lacking. In many areas, coast Douglas-fir needles are a staple in the spring diet of blue grouse ( Dendragapus ). In the winter, New World porcupines primarily eat the inner bark of young conifers, among which they prefer Douglas-fir. Douglas-fir seeds are an extremely important food for small mammals. Mice, voles, shrews, and chipmunks consumed an estimated 65 percent of

9991-626: The word forest is commonly used, there is no universally recognised precise definition, with more than 800 definitions of forest used around the world. Although a forest is usually defined by the presence of trees, under many definitions an area completely lacking trees may still be considered a forest if it grew trees in the past, will grow trees in the future, or was legally designated as a forest regardless of vegetation type. There are three broad categories of definitions of forest in use: administrative, land use , and land cover . Administrative definitions are legal designations, and may not reflect

10094-461: The word is a Latinisation of the Frankish * forhist , denoting "forest, wooded country", and was assimilated to forestam silvam , pursuant to the common practice of Frankish scribes. The Old High German forst denoting "forest"; Middle Low German vorst denoting "forest"; Old English fyrhþ denoting "forest, woodland, game preserve, hunting ground" (English frith ); and Old Norse fýri , denoting " coniferous forest "; all of which derive from

10197-579: The world's forest area is found in patches larger than 1 million hectares (2.5 million acres). The remaining 20 percent is located in more than 34 million patches around the world – the vast majority less than 1,000 hectares (2,500 acres) in size. Human society and forests can affect one another positively or negatively. Forests provide ecosystem services to humans and serve as tourist attractions. Forests can also affect people's health. Human activities, including unsustainable use of forest resources, can negatively affect forest ecosystems. Although

10300-416: The world's forests into 26 major types, which reflect climatic zones as well as the principal types of trees. These 26 major types can be reclassified into 6 broader categories: temperate needleleaf, temperate broadleaf and mixed, tropical moist, tropical dry, sparse trees and parkland, and forest plantations. Each category is described in a separate section below. Temperate needleleaf forests mostly occupy

10403-420: The world's land area in 2020. Forests are the largest terrestrial ecosystems of Earth by area, and are found around the globe. 45 percent of forest land is in the tropical latitudes . The next largest share of forests are found in subarctic climates , followed by temperate , and subtropical zones. Forests account for 75% of the gross primary production of the Earth's biosphere , and contain 80% of

10506-436: Was deciduous , dropping its fronds onto the forest floor, the shade, soil, and forest duff from the dropped fronds creating the early forest. The shed organic matter altered the freshwater environment, slowing its flow and providing food. This promoted freshwater fish. Forests account for 75% of the gross primary productivity of the Earth's biosphere , and contain 80% of the Earth's plant biomass. Biomass per unit area

10609-562: Was 393 feet (120 m), the Mineral Tree ( Mineral, Washington ), a coast Douglas fir, measured in 1924 by Dr. Richard E. McArdle, former chief of the U.S. Forest Service. The volume of that tree was 515 cubic metres (18,190 cu ft). Research suggests Douglas fir could grow to a maximum height of between 430 to 476 feet (131 to 145 m), at which point water supply would fail. Unconfirmed reports of even taller individuals may be found in historic records. The tallest tree in

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