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76-497: Modern forestry generally embraces a broad range of concerns, in what is known as multiple-use management, including: the provision of timber , fuel wood, wildlife habitat , natural water quality management , recreation , landscape and community protection, employment, aesthetically appealing landscapes , biodiversity management, watershed management , erosion control , and preserving forests as " sinks " for atmospheric carbon dioxide . Forest ecosystems have come to be seen as

152-619: A free content work. Licensed under CC BY-SA 3.0 ( license statement/permission ). Text taken from Global Forest Resources Assessment 2020 Key findings​ , FAO, FAO. [REDACTED]  This article incorporates text from a free content work. Licensed under CC BY-SA 3.0 IGO ( license statement/permission ). Text taken from The State of the World's Forests 2020. Forests, biodiversity and people – In brief​ , FAO & UNEP, FAO & UNEP. [REDACTED]  This article incorporates text from

228-527: A free content work. Licensed under CC BY-SA IGO 3.0 ( license statement/permission ). Text taken from World Food and Agriculture – Statistical Yearbook 2023​ , FAO, FAO. Timber Lumber is wood that has been processed into uniform and useful sizes (dimensional lumber), including beams and planks or boards . Lumber is mainly used for construction framing , as well as finishing (floors, wall panels , window frames ). Lumber has many uses beyond home building. Lumber

304-647: A rip saw is the most common method, because sawing allows logs of lower quality, with irregular grain and large knots, to be used and is more economical. There are various types of sawing: Dimensional lumber is lumber that is cut to standardized width and depth, often specified in millimetres or inches (but see below for information on nominal dimensions vs. actual dimensions). Carpenters extensively use dimensional lumber in framing wooden buildings. Common sizes include 2×4 (pictured) (also two-by-four and other variants, such as four-by-two in Australia, New Zealand, and

380-455: A "class 1 flame spread rating of 25 or less, when tested in accordance with ASTM standard E 84," which means it burns more slowly than almost all treated wood lumber. A timber mark is a code beaten on to cut wood by a specially made hammer to show the logging licence. The basic understanding of lumber, or "sawn planks", came about in North America in the seventeenth century. Lumber is

456-400: A 1-inch-thick (25 mm) board, 8/4 (eight quarter) is a 2-inch-thick (51 mm) board, etc. This "quarter" system is rarely used for softwood lumber; although softwood decking is sometimes sold as 5/4, even though it is actually one inch thick (from milling 1 ⁄ 8  in or 3.2 mm off each side in a motorized planing step of production). The "quarter" system of reference is

532-534: A 10-foot-long (3.0 m) 2×4 ( 1 + 1 ⁄ 2 by 3 + 1 ⁄ 2  in or 38 by 89 mm) into two 1×4s ( 3 ⁄ 4 by 3 + 1 ⁄ 2  in or 19 by 89 mm) of the same length is considered re-sawing. Structural lumber may also be produced from recycled plastic and new plastic stock. Its introduction has been strongly opposed by the forestry industry. Blending fiberglass in plastic lumber enhances its strength, durability, and fire resistance. Plastic fiberglass structural lumber can have

608-594: A faculty at the Federal University of Paraná , in Curitiba. Today, forestry education typically includes training in general biology , ecology , botany , genetics , soil science , climatology , hydrology , economics and forest management . Education in the basics of sociology and political science is often considered an advantage. Professional skills in conflict resolution and communication are also important in training programs. In India, forestry education

684-467: A framer much time, because they are pre-cut by the manufacturer for use in 8-, 9-, and 10-foot ceiling applications, which means the manufacturer has removed a few inches or centimetres of the piece to allow for the sill plate and the double top plate with no additional sizing necessary. In the Americas, two-bys (2×4s, 2×6s, 2×8s, 2×10s, and 2×12s), named for traditional board thickness in inches, along with

760-487: A lengthy dry season precludes evergreen vegetation, instead promoting the predominance of deciduous trees. During the fall months, each stem in a deciduous plant cuts off the flow of nutrients and water to the leaves. This causes them to change colors as the chlorophyll in the leaves breaks down. Special cells are formed that sever the connection between the leaf and stem, so that it will easily detach. Evergreen plants do not shed their leaves, merely go into

836-450: A mixture of the two. Techniques include timber extraction, planting and replanting of different species , building and maintenance of roads and pathways through forests, and preventing fire . The first dedicated forestry school was established by Georg Ludwig Hartig at Hungen in the Wetterau , Hesse , in 1787, though forestry had been taught earlier in central Europe, including at

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912-454: A region. A related discipline is the study of sylvics, which focuses on the autecology of genera and species. The provenance of forest reproductive material used to plant forests has a great influence on how the trees develop, hence why it is important to use forest reproductive material of good quality and of high genetic diversity . More generally, all forest management practices, including in natural regeneration systems , may impact

988-399: A relatively small set of specified lengths; in all cases hardwoods are sold to the consumer by the board-foot (144 cubic inches or 2,360 cubic centimetres), whereas that measure is not used for softwoods at the retailer (to the cognizance of the buyer). Also in North America, hardwood lumber is commonly sold in a "quarter" system, when referring to thickness; 4/4 (four quarter) refers to

1064-401: A state of low activity during the dormant season (in order to acclimate to cold temperatures or low rainfall ). During spring , the roots begin sending nutrients back up to the canopy . When the growing season resumes, either with warm weather or the wet season, the plant will break bud by sending out new leaf or flower growth. This is accompanied by growth of new stems from buds on

1140-413: A stronger dominance on conifers than broadleaf plants, thus conifers will normally grow a single straight trunk without forking or large side or lateral branches. As a woody plant grows, it will often lose lower leaves and branches as they become shaded out by the canopy (biology) . If a given stem is producing an insufficient amount of energy for the plant, the roots will "abort" it by cutting off

1216-438: A terminal bud, the side buds will have nothing to suppress them and begin rapidly sending out growth, if cut during spring . By late summer and early autumn , most active growth for the season has ceased and pruning a stem will result in little or no new growth. Winter buds are formed when the dormant season begins. Depending on the plant, these buds contain either new leaf growth, new flowers , or both. Terminal buds have

1292-449: A timber is referred to as one "timber" (材), and the dimensions of other structural components were quoted in multiples of "timber"; thus, as the width of the actual timber varied, the dimensions of other components were easily calculated, without resorting to specific figures for each scale. The dimensions of timbers in similar applications show a gradual diminution from the Sui dynasty (580–618) to

1368-443: A traditional North American lumber industry nomenclature used specifically to indicate the thickness of rough sawn hardwood lumber. In rough-sawn lumber it immediately clarifies that the lumber is not yet milled, avoiding confusion with milled dimension lumber which is measured as actual thickness after machining. Examples – 3 ⁄ 4 -inch, 19 mm, or 1x. In recent years architects, designers, and builders have begun to use

1444-426: A unit of dimensional lumber is limited by the height and girth of the tree it is milled from. In general the maximum length is 24 ft (7.32 m). Engineered wood products, manufactured by binding the strands, particles, fibers, or veneers of wood, together with adhesives, to form composite materials, offer more flexibility and greater structural strength than typical wood building materials. Pre-cut studs save

1520-912: Is an important economic segment in various industrial countries, as forests provide more than 86 million green jobs and support the livelihoods of many more people. For example, in Germany, forests cover nearly a third of the land area, wood is the most important renewable resource , and forestry supports more than a million jobs and about €181 billion of value to the German economy each year. Worldwide, an estimated 880 million people spend part of their time collecting fuelwood or producing charcoal, many of them women. Human populations tend to be low in areas of low-income countries with high forest cover and high forest biodiversity, but poverty rates in these areas tend to be high. Some 252 million people living in forests and savannahs have incomes of less than US$ 1.25 per day. Over

1596-419: Is available in many species, including hardwoods and softwoods , such as white pine and red pine , because of their low cost. Finished lumber is supplied in standard sizes, mostly for the construction industry – primarily softwood , from coniferous species, including pine , fir and spruce (collectively spruce-pine-fir ), cedar , and hemlock , but also some hardwood, for high-grade flooring. It

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1672-543: Is critical, such as trusses , rafters , laminating stock, I-beams and web joints. Machine grading measures a characteristic such as stiffness or density that correlates with the structural properties of interest, such as bending strength . The result is a more precise understanding of the strength of each piece of lumber than is possible with visually graded lumber, which allows designers to use full-design strength and avoid overbuilding. In Europe, strength grading of rectangular sawn lumber/timber (both softwood and hardwood)

1748-633: Is done according to EN-14081 and commonly sorted into classes defined by EN-338. For softwoods, the common classes are (in increasing strength) C16, C18, C24, and C30. There are also classes specifically for hardwoods and those in most common use (in increasing strength) are D24, D30, D40, D50, D60, and D70. For these classes, the number refers to the required 5th percentile bending strength in newtons per square millimetre. There are other strength classes, including T-classes based on tension intended for use in glulam . Grading rules for African and South American sawn lumber have been developed by ATIBT according to

1824-620: Is imparted in the agricultural universities and in Forest Research Institutes (deemed universities). Four year degree programmes are conducted in these universities at the undergraduate level. Masters and Doctorate degrees are also available in these universities. In the United States, postsecondary forestry education leading to a Bachelor's degree or Master's degree is accredited by the Society of American Foresters . In Canada

1900-609: Is mainly suitable to regions with small-scale multi-functional forest management systems Forestry literature is the books, journals and other publications about forestry. The first major works about forestry in the English language included Roger Taverner 's Booke of Survey (1565), John Manwood 's A Brefe Collection of the Lawes of the Forrest (1592) and John Evelyn 's Sylva (1662). [REDACTED]  This article incorporates text from

1976-406: Is minimally 1 + 1 ⁄ 2 by 3 + 1 ⁄ 2 inches (38 mm × 89 mm). As previously noted, less wood is needed to produce a given finished size than when standards called for the green lumber to be the full nominal dimension. However, even the dimensions for finished lumber of a given nominal size have changed over time. In 1910, a typical finished 1-inch (25 mm) board

2052-551: Is more commonly made from softwood than hardwoods, and 80% of lumber comes from softwood. In the United States and Canada, milled boards are called lumber , while timber describes standing or felled trees. In contrast, in Britain, and some other Commonwealth nations and Ireland, the term timber is used in both senses. (In the UK, the word lumber is rarely used in relation to wood and has several other meanings.) Re-manufactured lumber

2128-520: Is no sharp boundary between plant taxonomy and dendrology; woody plants not only belong to many different plant families , but these families may be made up of both woody and non-woody members. Some families include only a few woody species . Dendrology, as a discipline of industrial forestry, tends to focus on identification of economically useful woody plants and their taxonomic interrelationships. As an academic course of study, dendrology will include all woody plants, native and non-native, that occur in

2204-552: Is referred to as timber in the United Kingdom, Europe, Australia, and New Zealand, while in other parts of the world (mainly the United States and Canada) the term timber refers specifically to unprocessed wood fiber , such as cut logs or standing trees that have yet to be cut. Lumber may be supplied either rough- sawn , or surfaced on one or more of its faces. Rough lumber is the raw material for furniture-making, and manufacture of other items requiring cutting and shaping. It

2280-591: Is required. Under the prescription of the Method of Construction (營造法式) issued by the Song dynasty government in the early twelfth century, timbers were standardized to eight cross-sectional dimensions. Regardless of the actual dimensions of the timber, the ratio between width and height was maintained at 1:1.5. Units are in Song dynasty inches (31.2 mm). Timber smaller than the 8th class were called "unclassed" (等外). The width of

2356-459: Is smaller than the nominal dimensions because modern technology makes it possible to use the logs more efficiently. For example, a "2×4" board historically started out as a green, rough board actually 2 by 4 inches (51 mm × 102 mm). After drying and planing, it would be smaller by a nonstandard amount. Today, a "2×4" board starts out as something smaller than 2 inches by 4 inches and not specified by standards, and after drying and planing

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2432-422: Is still continued in some places. Otherwise, logs were sawn using a two-person whipsaw, or pit-saw, using saddleblocks to hold the log, and a pit for the pitman who worked below. In 1420 the island of Madeira  – an archipelago comprising four islands off the northwest coast of Africa and an autonomous region of Portugal – was discovered. King Henry VI sent settlers to Madeira and

2508-434: Is the biological science of studying forests and woodlands , incorporating the understanding of natural forest ecosystems , and the effects and development of silvicultural practices. The term complements silviculture , which deals with the art and practice of forest management. Silvology is seen as a single science for forestry and was first used by Professor Roelof A.A. Oldeman at Wageningen University . It integrates

2584-480: Is the extraction of forest products, are planned and managed to utilize a mix of ecological and agroecological principles. In many regions of the world there is considerable conflict between forest practices and other societal priorities such as water quality, watershed preservation, sustainable fishing, conservation, and species preservation. Silvology ( Latin : silva or sylva , "forests and woods"; Ancient Greek : -λογία , -logia , "science of" or "study of")

2660-430: Is the foundation of biological diversity at species and ecosystem levels. Forest genetic resources are therefore important to consider in forest management. Genetic diversity in forests is threatened by forest fires , pests and diseases, habitat fragmentation , poor silvicultural practices and inappropriate use of forest reproductive material. About 98 million hectares of forest were affected by fire in 2015; this

2736-437: Is the result of secondary or tertiary processing of previously milled lumber. Specifically, it refers to lumber cut for industrial or wood-packaging use. Lumber is cut by ripsaw or resaw to create dimensions that are not usually processed by a primary sawmill . Re-sawing is the splitting of 1-to-12-inch (25–305 mm) hardwood or softwood lumber into two or more thinner pieces of full-length boards. For example, splitting

2812-605: Is well utilised in the construction industry. Attempts to maintain lumber quality over time have been challenged by historical changes in the timber resources of the United States – from the slow-growing virgin forests common over a century ago to the fast-growing plantations now common in today's commercial forests. Resulting declines in lumber quality have been of concern to both the lumber industry and consumers and have caused increased use of alternative construction products. Machine stress-rated and machine-evaluated lumber are readily available for end-uses where high strength

2888-503: The American Lumber Standard Committee , appointed by the U.S. Secretary of Commerce . Design values for most species and grades of visually graded structural products are determined in accordance with ASTM standards, which consider the effect of strength reducing characteristics, load duration, safety, and other influencing factors. The applicable standards are based on results of tests conducted in cooperation with

2964-702: The American colonies began in 1607 when the Jamestown settlers cut timber to build the first settlement in the new world. America's first sawmill was built at the Falls of Piscatauqua , on the line between the Province of Maine and the Province of New Hampshire , in 1634. Unauthenticated records, however, claim that as early as 1633 several mills were operating in New Netherland . The American colonies were essential to England in

3040-539: The USDA Forest Products Laboratory. Design Values for Wood Construction, which is a supplement to the ANSI/AF&;PA National Design Specification® for Wood Construction, provides these lumber design values, which are recognized by the model building codes. Canada has grading rules that maintain a standard among mills manufacturing similar woods to assure customers of uniform quality. Grades standardize

3116-679: The University of Giessen , in Hesse-Darmstadt . In Spain, the first forestry school was the Forest Engineering School of Madrid ( Escuela Técnica Superior de Ingenieros de Montes ), founded in 1844. The first in North America, the Biltmore Forest School was established near Asheville , North Carolina, by Carl A. Schenck on September 1, 1898, on the grounds of George W. Vanderbilt's Biltmore Estate . Another early school

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3192-737: The effects of climate change . Most countries in Europe have recommendations or guidelines for selecting species and provenances that can be used in a given site or zone. Forest management is a branch of forestry concerned with overall administrative, legal, economic, and social aspects, as well as scientific and technical aspects, such as silviculture , forest protection , and forest regulation . This includes management for timber, aesthetics , recreation , urban values, water , wildlife , inland and nearshore fisheries, wood products , plant genetic resources , and other forest resource values . Management objectives can be for conservation, utilisation, or

3268-404: The "quarter" system in specifications as a vogue of insider knowledge, though the materials being specified are finished lumber, thus conflating the separate systems and causing confusion. Hardwoods cut for furniture are cut in the fall and winter, after the sap has stopped running in the trees. If hardwoods are cut in the spring or summer the sap ruins the natural color of the lumber and decreases

3344-409: The 4×4 (89 mm × 89 mm), are common lumber sizes used in modern construction. They are the basic building blocks for such common structures as balloon-frame or platform-frame housing. Dimensional lumber made from softwood is typically used for construction, while hardwood boards are more commonly used for making cabinets or furniture. Lumber's nominal dimensions are larger than

3420-1182: The Canadian Institute of Forestry awards silver rings to graduates from accredited university BSc programs, as well as college and technical programs. In many European countries, training in forestry is made in accordance with requirements of the Bologna Process and the European Higher Education Area . The International Union of Forest Research Organizations is the only international organization that coordinates forest science efforts worldwide. In order to keep up with changing demands and environmental factors, forestry education does not stop at graduation. Increasingly, forestry professionals engage in regular training to maintain and improve on their management practices. An increasingly popular tool are marteloscopes ; one hectare large, rectangular forest sites where all trees are numbered, mapped and recorded. These sites can be used to do virtual thinnings and test one's wood quality and volume estimations as well as tree microhabitats . This system

3496-825: The UK), 2×6 , and 4×4 . The length of a board is usually specified separately from the width and depth. It is thus possible to find 2×4s that are four, eight, and twelve feet in length. In Canada and the United States, the standard lengths of lumber are 6, 8, 10, 12, 14, 16, 18, 20, 22 and 24 feet (1.8, 2.4, 3.0, 3.7, 4.3, 4.9, 5.5, 6.1, 6.7 and 7.3 m). For wall framing, precut "stud" lengths are available, and are commonly used. For ceilings heights of 8, 9 or 10 feet (2.4, 2.7 or 3.0 m), studs are available in 92 + 5 ⁄ 8 inches (2.35 m), 104 + 5 ⁄ 8 inches (2.66 m), and 116 + 5 ⁄ 8 inches (2.96 m). The length of

3572-499: The United States began with the publication of the American Lumber Standard in 1924, which set specifications for lumber dimensions, grade, and moisture content; it also developed inspection and accreditation programs. These standards have changed over the years to meet the changing needs of manufacturers and distributors, with the goal of keeping lumber competitive with other construction products. Current standards are set by

3648-422: The actual standard dimensions of finished lumber. Historically, the nominal dimensions were the size of the green (not dried), rough (unfinished) boards that eventually became smaller finished lumber through drying and planing (to smooth the wood). Today, the standards specify the final finished dimensions and the mill cuts the logs to whatever size it needs to achieve those final dimensions. Typically, that rough cut

3724-435: The amount of oxygen is inadequate. Fungi lumber/timber defects: Following are the insects and molluscs which are usually responsible for the decay of timber/lumber: Woody plants A woody plant is a plant that produces wood as its structural tissue and thus has a hard stem. In cold climates, woody plants further survive winter or dry season above ground, as opposed to herbaceous plants that die back to

3800-402: The conversion of log timber into planks 30 times faster than previously. The circular saw, as used in modern sawmills, was invented by an Englishman named Miller in 1777. It was not until the nineteenth century, however, that it was generally applied, and its great work belongs to that period. The first insertable teeth for this saw were invented by W. Kendal, an American, in 1826. Logging in

3876-408: The countries with significant sawmilling industries. Historical wood-frame home building regions are: Europe, North America, Japan. Different areas of the world are recognized as significant timber suppliers; however, these areas (Indonesia, Sarawak, New Guinea, etc.) are exporters of raw logs and do not have a significant domestic lumber producing industry. The largest lumber manufacturing regions in

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3952-421: The flow of water and nutrients , causing it to gradually die. Below ground , the root system expands each growing season in much the same manner as the stems . The roots grow in length and send out smaller lateral roots. At the end of the growing season, the newly grown roots become woody and cease future length expansion, but will continue to expand in diameter. However, unlike the above-ground portion of

4028-646: The genetic diversity of trees. The term genetic diversity describes the differences in DNA sequence between individuals as distinct from variation caused by environmental influences. The unique genetic composition of an individual (its genotype ) will determine its performance (its phenotype ) at a particular site. Genetic diversity is needed to maintain the vitality of forests and to provide resilience to pests and diseases . Genetic diversity also ensures that forest trees can survive, adapt and evolve under changing environmental conditions. Furthermore, genetic diversity

4104-445: The ground until spring . Woody plants are usually trees , shrubs , or lianas . These are usually perennial plants whose stems and larger roots are reinforced with wood produced from secondary xylem . The main stem, larger branches, and roots of these plants are usually covered by a layer of bark . Wood is a structural tissue that allows woody plants to grow from above ground stems year after year, thus making some woody plants

4180-405: The inner side of a vascular cambium layer located immediately beneath the bark. However, in some monocotyledons such as palms and dracaenas , the wood is formed in bundles scattered through the interior of the trunk. Stem diameter increases continuously throughout the growing season and halts during the dormant period. The symbol for a woody plant, based on Species Plantarum by Linnaeus

4256-500: The largest and tallest terrestrial plants . Woody plants, like herbaceous perennials, typically have a dormant period of the year when growth does not take place. This occurs in temperate and continental due to freezing temperatures and lack of daylight during the winter months. Meanwhile, dormancy in subtropical and tropical climates is due to the dry season; when low precipitation limits water available for growth. The dormant period will be accompanied by abscission (if

4332-543: The modern era; a 1st class timber during the Sui was reconstructed as 15×10 (Sui dynasty inches, or 29.4 mm). Defects occurring in lumber are grouped into the following four divisions: During the process of converting timber to commercial forms of lumber the following defects may occur: Fungi attack wood (both timber and lumber) when these conditions are all present: Wood with less than 25% moisture (dry weight basis) can remain free of decay for centuries. Similarly, wood submerged in water may not be attacked by fungi if

4408-491: The most common and widely used method of sawing logs. Plain sawn lumber is produced by making the first cut on a tangent to the circumference of the log. Each additional cut is then made parallel to the one before. This method produces the widest possible boards with the least amount of log waste. Lumber manufacturing globally is determined by the preferred style of building; areas with a "wood building culture" (homes were built from wood rather than other materials like brick) are

4484-440: The most important component of the biosphere , and forestry has emerged as a vital applied science , craft , and technology . A practitioner of forestry is known as a forester . Another common term is silviculturist. Silviculture is narrower than forestry, being concerned only with forest plants, but is often used synonymously with forestry. All people depend upon forests and their biodiversity, some more than others. Forestry

4560-400: The outer handful of rings contain living tissue (the cambium , xylem , phloem , and sapwood ). Inner layers have heartwood, dead tissue that serves merely as structural support. Stem growth primarily occurs out of the terminal bud on the tip of the stem. Axillary buds are suppressed by the terminal bud and produce less growth, unless it is removed by human or natural action. Without

4636-439: The past centuries, forestry was regarded as a separate science. With the rise of ecology and environmental science , there has been a reordering in the applied sciences. In line with this view, forestry is a primary land-use science comparable with agriculture . Under these headings, the fundamentals behind the management of natural forests comes by way of natural ecology. Forests or tree plantations, those whose primary purpose

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4712-420: The plant is deciduous ). Evergreen plants do not lose all their leaves at once (they instead shed them gradually over the growing season ), however growth virtually halts during the dormant season. Many woody plants native to the subtropics and tropics are evergreen due to year-round warm temperatures and rainfall. However, in many regions with a tropical savanna climate or a monsoon subtropical climate ,

4788-545: The plant, the root system continues to grow, although at a slower rate, throughout the dormant season. In cold-weather climates , root growth will continue as long as temperatures are above 2 °C (36 °F). Wood is primarily composed of xylem cells with cell walls made of cellulose and lignin . Xylem is a vascular tissue which moves water and nutrients from the roots to the leaves. Most woody plants form new layers of woody tissue each year, and so increase their stem diameter from year to year, with new wood deposited on

4864-458: The previous season's wood. In colder climates, most stem growth occurs during spring and early summer. When the dormant season begins, the new growth hardens off and becomes woody. Once this happens, the stem will never grow in length again, however it will keep expanding in diameter for the rest of the plant's life. Most woody plants native to colder climates have distinct growth rings produced by each year's production of new vascular tissue. Only

4940-505: The quality of lumber at different levels and are based on moisture content, size, and manufacture at the time of grading, shipping, and unloading by the buyer. The National Lumber Grades Authority (NLGA) is responsible for writing, interpreting and maintaining Canadian lumber grading rules and standards. The Canadian Lumber Standards Accreditation Board (CLSAB) monitors the quality of Canada's lumber grading and identification system. Their common grade abbrievation, CLS, Canadian Lumber Standard

5016-653: The role of supplier of lumber for the British fleet. By the 1790s, New England was exporting 36 million feet of pine boards and at least 300 ship masts per year to the British Empire. The timber supply began to dwindle at the start of the twentieth century due to significant harvest volumes, so the logging industry was forced to seek timber elsewhere; hence, the expansion into the American West. Logs are converted into lumber by being sawn, hewn , or split . Sawing with

5092-511: The rules of the Sciages Avivés Tropicaux Africains (SATA) and is based on clear cuttings – established by the percentage of the clear surface. In North America, market practices for dimensional lumber made from hardwoods varies significantly from the regularized standardized ' dimension lumber ' sizes used for sales and specification of softwoods – hardwood boards are often sold totally rough cut, or machine planed only on

5168-446: The settlers started clearing the huge expanses of forest in order to grow crops. Felled trees were made into planks by water-powered mills and the timber (cedar and yew) was shipped to Portugal and Spain. About 1427, the first sawmill in Germany was built. Cornelis Corneliszoon (or Krelis Lootjes) was a Dutch windmill owner from Uitgeest who invented the first mechanical sawmill, which was wind-powered, on 15 December 1593. This made

5244-434: The study of forests and forest ecology, dealing with single tree autecology and natural forest ecology . Dendrology ( Ancient Greek : δένδρον , dendron , "tree"; and Ancient Greek : -λογία , -logia , science of or study of ) or xylology ( Ancient Greek : ξύλον , ksulon , "wood") is the science and study of woody plants ( trees , shrubs , and lianas ), specifically, their taxonomic classifications. There

5320-453: The two (broader) face sides. When hardwood boards are also supplied with planed faces, it is usually both by random widths of a specified thickness (normally matching milling of softwood dimensional lumber) and somewhat random lengths. But besides those older (traditional and normal) situations, in recent years some product lines have been widened to also market boards in standard stock sizes; these usually retail in big-box stores and using only

5396-459: The value of the wood for furniture. Engineered lumber is lumber created by a manufacturer and designed for a certain structural purpose. The main categories of engineered lumber are: In the United States, pilings are mainly cut from southern yellow pines and Douglas-fir . Treated pilings are available in chromated copper arsenate retentions of 0.60, 0.80 and 2.50 pounds per cubic foot (9.6, 12.8 and 40.0 kg/m ) if treatment

5472-424: The world are: China (18%); United States (17%); Canada (10%); Russia (9%); Germany (5%); Sweden (4%). In early periods of society, to make wood for building, the trunks of trees were split with wedges into as many and as thin pieces as possible. If it was necessary to have them still thinner, they were hewn, by some sharp instrument, on both sides, to the proper size. This simple but wasteful manner of making boards

5548-514: Was 13 ⁄ 16  in (21 mm). In 1928, that was reduced by 4%, and yet again by 4% in 1956. In 1961, at a meeting in Scottsdale, Arizona, the Committee on Grade Simplification and Standardization agreed to what is now the current U.S. standard: in part, the dressed size of a 1-inch (nominal) board was fixed at 3 ⁄ 4  inch; while the dressed size of 2 inch (nominal) lumber

5624-516: Was reduced from 1 + 5 ⁄ 8  inch to the current 1 + 1 ⁄ 2  inch. Dimensional lumber is available in green, unfinished state, and for that kind of lumber, the nominal dimensions are the actual dimensions. Individual pieces of lumber exhibit a wide range in quality and appearance with respect to knots, slope of grain, shakes and other natural characteristics. Therefore, they vary considerably in strength, utility, and value. The move to set national standards for lumber in

5700-477: Was mainly in the tropical domain, where fire burned about 4 percent of the total forest area in that year. More than two-thirds of the total forest area affected was in Africa and South America. Insects, diseases and severe weather events damaged about 40 million hectares of forests in 2015, mainly in the temperate and boreal domains. Furthermore, the marginal populations of many tree species are facing new threats due to

5776-625: Was the New York State College of Forestry , established at Cornell University just a few weeks later, in September 1898. Early 19th century North American foresters went to Germany to study forestry. Some early German foresters also emigrated to North America. In South America the first forestry school was established in Brazil, in Viçosa , Minas Gerais , in 1962, and moved the next year to become

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