NationMaster - Encyclopedia: Heartwood

Download high resolution version (904x606, 103 KB)tree trunk as seen on the Veluwe, The Netherlands Author: me, Paul Vlaar Date: 2001-04-01 Source: http://www.neep.net/photo/unsorted/show.php?1861 File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert...

A tree trunk as found at the The Veluwe is a forest-rich area in the middle of the Netherlands. In the center of the Veluwe lies the Netherlands biggest national park, Nationaal Park de Hoge Veluwe, best translated as upper Veluwe because of its elevation. The Veluwe features many different landscapes including woodland, heath, lakes and... Veluwe, Netherlands (disambiguation). The Netherlands ( Dutch: Nederland) is the European part of the Kingdom of the Netherlands ( Dutch: Koninkrijk der Nederlanden). The Netherlands is a parliamentary democracy under a constitutional monarch, located in northwestern Europe. It borders the North Sea to the north and west, Belgium to the south, and Germany... The Netherlands

Wood is a material is the substance or matter from which something is or can be made, or also items needed for doing or creating something. material is sometimes used when referring to cloth or fabric. materials are inputs to production or manufacturing. They are often raw - that is unprocessed, but are sometimes... material found as the primary content of the stems of A woody plant is any vascular plant that has a perennial woody stem -- that is, one that supports continued vegetative growth above ground from year to year. Many annuals appear to form woody stems in their first year, but nonetheless die back. A true woody stem contains wood, which is... woody plants, especially This article is about the biological organisms known as trees. For other meanings of the word see tree (disambiguation). The coniferous Coast Redwood, the tallest tree species on earth A tree can be defined as a large, perennial, woody plant. Though there is no set definition regarding minimum size, the... trees, but also The word bush re-directs here; for alternate uses see Bush (disambiguation). Shrub is also a derogatory nickname for United States President George W Bush. A willow shrub A shrub or bush is a horticultural rather than strictly botanical category of woody plant, distinguished from a tree by its multiple... shrubs. These A Red Valerian, a perennial plant. A perennial plant or perennial (Latin per, through, annus, year) is a plant that produces flowers and seeds more than one time in its lifespan, and therefore lives for more than one year. This term is usually applied to herbaceous plants or small shrubs... perennial plants are characterised by stems that grow outward year after year, and that are composed of Cellulose ( C6 H10 O5)n is a long-chain polymer polysaccharide carbohydrate, of beta-glucose. It forms the primary structural component of plants and is not digestible by humans. History and Applications Cellulose is a common material in plant cell walls and was first noted as such in 1838. It... cellulose and Lignin is a chemical compound that is an integral part of the cell walls of some cells, eg tracheids, xylary fibres and sclereids of plants. Lignin is formed by the irreversible removal of water from sugars, creating aromatic compounds through the phenylpropanoid pathway. Lignin polymers are cross-connected structures with... lignin based tissue. Plants that do not produce wood are called ' This article is about the plants used in cooking and medicine. For the New Zealand reggae band, see Herbs (band). A herb (pronounced urb in American English and hurb in British English) is a plant grown for culinary or medicinal value. Typically, the green, leafy part of the plant is... herbaceous'; this group of plants includes all annual plants, many perennial plants, and most submerged and floating aquatic plants.

The woody tissue is formed by the plant for structural purposes, and because it is an effective and efficient structural material, it is useful to humans. Wood is made of Cellulose ( C6 H10 O5)n is a long-chain polymer polysaccharide carbohydrate, of beta-glucose. It forms the primary structural component of plants and is not digestible by humans. History and Applications Cellulose is a common material in plant cell walls and was first noted as such in 1838. It... cellulose fibers, held together with Lignin is a chemical compound that is an integral part of the cell walls of some cells, eg tracheids, xylary fibres and sclereids of plants. Lignin is formed by the irreversible removal of water from sugars, creating aromatic compounds through the phenylpropanoid pathway. Lignin polymers are cross-connected structures with... lignin.

When cut down and dried, wood is used for many different purposes. Wood that is broken down into Wood fibres are (usually) cellulosic elements that are extracted from trees, straw, bamboo, cotton seed, hemp and sugar cane to name just a few sources. The dimensions of individual fibres typically used in North America can range from 0.5 mm to 30 mm (0.02-1.2) in length... fibers is called Wood pulp is the most common material used to make paper. The timber resources used to make wood pulp are referred to as pulpwood. Wood pulp generally comes from softwood trees such as spruce, pine, fir, larch and hemlock, but also some hardwoods such as eucalyptus and birch. International Paper... pulp, which may then be made into Piece of paper Paper is a thin, flat material produced by the compression of fibres. The fibers used are usually natural and based upon cellulose. The most common material is wood pulp from pulpwood (largely softwood) trees such as spruces, but other vegetable fiber materials including cotton, linen, and hemp... paper. Artists and craftsmen shape and join pieces of wood with special tools, which is called Artists can use woodworking to create delicate sculptures. Woodworking is the process of building, making or carving something using wood. History Along with stone, mud, and animal parts, wood was certainly one of the first materials worked by primitive man. Indeed, the development of civilization was closely tied to the... woodworking or A carpenter is a skilled craftsman who performs carpentry -- a wide range of woodworking that includes constructing buildings, furniture, and other large objects out of wood. Since most of carpentrys required knowledge is gained through experience, the profession is relatively easy to enter, but the job usually does not... carpentry. Wood has been an important Construction on the North Bytown Bridge in Ottawa, Canada. A crane is readied to lower a barge into the water. This barge will be placed under any cutting work on the bridge to lessen the environmental impact. Note the concrete barricades and snow fencing in place to protect the public... construction material since humans began building shelters, and remains in plentiful use today. Construction wood is commonly known as Timber Timber is a term used to describe clusters of trees. It is also used to describe wood throughout its processing from the time it is cut down to the time it is used as a structural material. The word TIMBER! is also used as an exclamation when a tree... timber in International English is the concept of the English language as a global means of communication in numerous dialects, and the movement towards an international standard for the language. It is sometimes referred to as Global English, World English or Standard English. Sometimes these terms refer simply to the array of... International English, and Lumber is the name used, generally in North America, for wood that has been cut into boards or other shapes for the purpose of woodworking or construction. Lumber is supplied either rough or finished. Rough lumber is the raw material for furniture making and other items requiring additional cutting and... lumber in American English or U.S. English is the diverse form of the English language used mostly in the United States of America. It is the primary language used in the United States. According to the 1990 census, 97 percent of U.S. residents speak English well or very well. Only... American English.

In modern times, many of the traditional uses of wood may be filled by For alternative meanings see metal (disambiguation). In chemistry, a metal ( Greek: Metallon) is an element that readily forms ions (cations) and has metallic bonds, and it is sometimes said that it is similar to a cation in a cloud of electrons. The metals are one of the three groups of... metal and The term plastics covers a range of synthetic or semi-synthetic organic condensation or polymerization products that can be molded or extruded into objects or films or fibers. Their name is derived from the fact that in their semi-liquid state they are malleable, or have the property of plasticity... plastics. Medium-density fibreboard (MDF), is an engineered wood product formed by breaking down softwood into wood fibres, often in a defibrator, combining it with wax and resin, and forming panels by applying high temperature and pressure. Large-scale production of MDF began in the 1980s. Its name derives from the... Medium-density fibreboard, a product of woods, is also used as a cheap alternative to traditional woods.

Wood is commonly classified as either Beech is a typical temperate zone hardwood The term hardwood designates wood from angiosperm trees. Hardwood contrasts with softwood, which comes from gymnosperm (coniferous) trees. They are in general of higher density and hardness, but there is considerable variation in actual wood hardness in both groups, with a large amount... hardwood or Categories: Stub | Wood ... softwood. The wood from Orders & Families Cordaitales † Pinales Pinaceae - Pine family Araucariaceae - Araucaria family Podocarpaceae - Yellow-wood family Sciadopityaceae - Umbrella-pine family Cupressaceae - Cypress family Cephalotaxaceae - Plum-yew family Taxaceae - Yew family Vojnovskyales † Voltziales † The conifers... conifers (e.g. This article deals with the tree; for the e-mail client see Pine email client Species About 115. Pines are coniferous trees of the genus Pinus, in the family Pinaceae. There are about 115 species of pine, although different authors accept anything from 105 to 125 species. Distribution Pines are... pine) is called softwood, and the wood from Classes Magnoliopsida - Dicots Liliopsida - Monocots The flowering plants (also angiosperms or Magnoliophyta) are one of the major groups of modern plants, comprising those that produce seeds in specialized reproductive organs called flowers, where the ovulary or carpel is enclosed. The other seed plants are called gymnosperms; here the ovule is... broad-leaved trees (e.g. This article is about oaks (Quercus). The Australian tree known as desert-oak is unrelated, and instead belongs to the genus Allocasuarina. OAK is also the three-letter IATA airport code for Oakland International Airport in Oakland, California USA. See also Oak, Nebraska, USA. Species See List of Quercus species... oak) is called hardwood. This classification is sometimes misleading, as some hardwoods (e.g. Binomial name Ochroma lagopus Balsa (Ochroma lagopus, synonym O. pyramidale) is a large, fast-growing tree to 30 m tall, native from tropical South America north to southern Mexico. It is evergreen, or dry-season deciduous if the dry season is long, with large (30-50 cm) weakly palmately lobed... balsa) are actually softer than most softwoods, and conversely, some softwoods (e.g. Species Taxus baccata - European Yew Taxus brevifolia - Pacific Yew Taxus canadensis - Canadian Yew Taxus chinensis - Chinese Yew Taxus cuspidata - Japanese Yew Taxus floridana - Florida Yew Taxus globosa - Mexican Yew Taxus sumatrana - Sumatran Yew Taxus wallichiana - Himalayan Yew Yews are small coniferous trees or shrubs in the genus Taxus in the... yew) are harder than most hardwoods.

Additionally, woods from different types of trees have different colors and grain densities. Because of these differences, and the fact that some woods take longer to grow than others, wood from different kinds of trees have different qualities and values. For example, while Genera and Species Entandophragma E. utile - Utile or African Mahogany Guarea G. cedrata - Pink Mahogany Khaya K. ivoriensis - Ivory Coast Mahogany K. senegalensis - Senegal Mahogany Swietenia S. macrophylla - Honduras Mahogany S. mahagoni - West Indian Mahogany Toona T. ciliata - Indian Mahogany T. sinensis - Chinese Mahogany This article is about the trees... mahogany is a dark, dense hardwood which is excellent for fine furniture crafting, Binomial name Ochroma lagopus Balsa (Ochroma lagopus, synonym O. pyramidale) is a large, fast-growing tree to 30 m tall, native from tropical South America north to southern Mexico. It is evergreen, or dry-season deciduous if the dry season is long, with large (30-50 cm) weakly palmately lobed... balsa is light, soft, and almost spongelike, making it useful for Model may refer to more than one thing : For models in society, art, fashion, and cosmetics, see; role model model (person) supermodel figure drawing modeling section In science and technology, a model (abstract) is understood as an abstract or theoretical representation of a phenomenon,see; geologic modeling model (economics... model building.

Knots

Knots are portions of Categories: Plant stubs ... branches included in the wood of the stem or larger branch. Branches generally originate at or near the The centre dark spot (about 1 mm diameter) in this yew wood is the pith Pith is a light substance that is found in vascular plants. It consists of soft, spongy parenchyma cells, and is located in the center of the stem or root. It is encircled by a ring... pith (central axis) of a A stem is the above ground axis of a vascular plant. The young stem develops in the germinating seedling from embryonic tissue known as the hypocotyl. Lengthening of the hypocotyl lifts the cotyledon(s), plumule (leaf precursor tissues), and terminal or apical meristem above the ground. The surface cells differentiate... stem, and the living portion will increase in size through the addition of annual woody layers which are a continuation of those of the stem. The included portion is irregularly conical in shape with the tip at the pith. The direction of the fibre is at right angles or oblique to the grain of the stem, thus producing local cross grain.

During the development of a tree most of the limbs, especially the lower ones, die, but persist for a time--often for years. Subsequent layers of growth of the stem are no longer intimately joined with the dead limb, but are laid around it. Hence dead branches produce knots which are nothing more than pegs in a hole, and likely to drop out after the tree has been sawn. In grading Lumber is the name used, generally in North America, for wood that has been cut into boards or other shapes for the purpose of woodworking or construction. Lumber is supplied either rough or finished. Rough lumber is the raw material for furniture making and other items requiring additional cutting and... lumber and structural Timber Timber is a term used to describe clusters of trees. It is also used to describe wood throughout its processing from the time it is cut down to the time it is used as a structural material. The word TIMBER! is also used as an exclamation when a tree... timber, knots are classified according to their form, size, soundness, and the firmness with which they are held in place.

Knots materially affect checking (cracking) and warping, ease in working, and cleavability of timber. They are defects which weaken timber and depreciate its value for structural purposes where strength is an important consideration. The weakening effect is much more serious where timber is subjected to bending and In physics, tension is a force on a body directed to produce strain (extension); it can be considered to be negative compression. It is measured in according units (newton, dynes, pounds-force, etc). Tension is the dominant static force acting on such objects as a vibrating string or a stretched... tension than where under Compression in material science, physics or structural engineering, is the stress state of materials where the volume tends to decrease (compaction). Compression is the result of the subjection of a material to compressive stress. There are some indications that astronomical observations of gamma-ray bursts are possibly due to compression... compression. The extent to which knots affect the strength of a A beam is a structural element that carries load primarily in bending (flexure). Beams generally carry vertical gravitational forces but can also be used to carry horizontal loads (i.e. loads due to a gust of wind or an earthquake). The loads carried by a beam are transferred to columns... beam depends upon their position, size, number, direction of For the meaning of fiber in nutrition, see dietary fiber. For the use of fiber in computer science and operating systems, see thread (computer science). For the use of fiber in computer networks and telecommunications, see optical fiber. Fiber (American English) or fibre (International English) consists of elongated stringy natural... fibre, and condition. A knot on the upper side is compressed, while one on the lower side is subjected to tension. The knot, especially (as is often the case) if there is a season check in it, offers little resistance to this tensile stress. Small knots, however, may be so located in a beam along the neutral plane as actually to increase the strength by tending to prevent longitudinal Shear stress is a stress state where the shape of a material tends to change (usually by sliding forces - torque by transversely-acting forces) without particular volume change. The shape change is evaluated by measuring the change of the angles magnitude (shear strain). In laboratory testing, shear stress is... shearing. Knots in a board or plank are least injurious when they extend through it at right angles to its broadest surface. Knots which occur near the ends of a beam do not weaken it. Sound knots which occur in the central portion one-fourth the height of the beam from either edge are not serious defects.

Knots do not materially influence the stiffness of structural timber. Only defects of the most serious character affect the elastic limit of beams. Stiffness and elastic strength are more dependent upon the quality of the wood fibre than upon defects in the beam. The effect of knots is to reduce the difference between the fibre stress at elastic limit and the modulus of rupture of beams. The breaking strength is very susceptible to defects. Sound knots do not weaken wood when subject to compression parallel to the grain.

For some purposes, e.g. wall panelling, knots are considered beneficial as they add visual texture to the wood, giving it a more interesting appearance.

Heartwood and sapwood

Yew wood showing 27 annual growth rings, pale sapwood and dark heartwood, and pith (centre dark spot). The dark radial lines are small knots. Photo User:MPF File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. Click on date...

A section of a Species Taxus baccata - European Yew Taxus brevifolia - Pacific Yew Taxus canadensis - Canadian Yew Taxus chinensis - Chinese Yew Taxus cuspidata - Japanese Yew Taxus floridana - Florida Yew Taxus globosa - Mexican Yew Taxus sumatrana - Sumatran Yew Taxus wallichiana - Himalayan Yew Yews are small coniferous trees or shrubs in the genus Taxus in the... Yew branch showing 27 annual growth rings, pale sapwood and dark heartwood, and The centre dark spot (about 1 mm diameter) in this yew wood is the pith Pith is a light substance that is found in vascular plants. It consists of soft, spongy parenchyma cells, and is located in the center of the stem or root. It is encircled by a ring... pith (centre dark spot). The dark radial lines are small knots.

Examination of the end of a A log is: a cut portion of a tree bole or large branch (see logging) a time-sequential data record (see data logging) logarithm a device to measure the speed of a ship This is a disambiguation page — a navigational aid which lists other pages that might otherwise share... log of many species reveals a darker-colored inner portion (the heartwood), surrounded by a lighter-colored zone (the sapwood). In some instances this distinction in color is very marked; in others, the contrast is slight, so that it is not always easy to tell where one leaves off and the other begins. The color of fresh sapwood is always light, sometimes nearly white, but more often with a decided tinge of yellow or brown.

Sapwood is comparatively new wood, comprising living Cells in culture, stained for keratin The cell is the structural and functional unit of all living organisms. Some organisms, such as bacteria, are unicellular, consisting of a single cell. Other organisms, such as humans, are multicellular, (humans have an estimated 100,000 billion = 1014 cells). The cell theory, first... cells in the growing tree. All wood in a tree is first formed as sapwood. Its principal functions are to conduct water from the For other meanings of root, see Root (disambiguation). In vascular plants, roots form the portions of a plant which generally lie below the level of the soil (cf. stem, rhizome). But this is not always characteristic for a root, since a root can also be an aerial root (i.e... roots to the This article is about the leaf, a plant organ. See Leaf (disambiguation) for other meanings. Fallen leaf of a maple. Note areas where chlorophyll (green) has been destroyed now appear yellow. In botany, a leaf is an above-ground plant organ specialized for photosynthesis. For this purpose, a leaf is... leaves and to store up and give back according to the season the food prepared in the leaves. The more leaves a tree bears and the more vigorous its growth, the larger the volume of sapwood required. Hence trees making rapid growth in the open have thicker sapwood for their size than trees of the same species growing in dense forests. Sometimes trees grown in the open may become of considerable size, 30 cm or more in diameter, before any heartwood begins to form, for example, in second-growth For other meanings of Hickory please see Hickory (disambiguation). Species See text Hickory is a tree of the genus Carya (which also includes Pecan). The genus includes about 25 species of deciduous trees with pinnately compound leaves and large nuts. All but one of the species are native to North... hickory, or open-grown This article deals with the tree; for the e-mail client see Pine email client Species About 115. Pines are coniferous trees of the genus Pinus, in the family Pinaceae. There are about 115 species of pine, although different authors accept anything from 105 to 125 species. Distribution Pines are... pines.

As a tree increases in age and diameter an inner portion of the sapwood becomes inactive and finally ceases to function, as the cells die. This inert or dead portion is called heartwood. Its name derives solely from its position and not from any vital importance to the tree. This is shown by the fact that a tree can thrive with its heart completely decayed. Some species begin to form heartwood very early in life, so having only a thin layer of live sapwood, while in others the change comes slowly. Thin sapwood is characteristic of such trees as This article is about the chestnut plant in the genus Castanea. The name horse-chestnut is commonly applied to several species in the unrelated genus Aesculus (family Sapindaceae). Chestnut is also used to describe a certain colour of coat in horses that resembles the colour of the chestnut nut. Species... chestnut, Binomial name Robinia pseudoacacia Black locust (Robinia pseudoacacia) is a tree in the subfamily Faboideae of the pea family Fabaceae. It is native to eastern North America from northeast Texas to New York, and widely planted and naturalised elsewhere in the rest of temperate North America, Europe and Asia. Similar... black locust, Species Morus alba - White Mulberry Morus australis - Chinese Mulberry Morus indica - Indian Mulberry Morus microphylla - Texas Mulberry Morus nigra - Black Mulberry Morus rubra - Red Mulberry Morus serrata - Himalayan Mulberry For other meanings, see Mulberry (disambiguation). Mulberry refers both to the mulberry tree and to the fruit of that tree. It... mulberry, Binomial name Maclura pomifera (Raf.) Schneid. The Osage-orange Maclura pomifera, is a curious plant in the mulberry family Moraceae. It is also known as hedge-apple, horse-apple, bois darc, bodark (in Texas), and bow wood. The species is dioeceous, with male and female flowers on different plants... osage-orange, and Species Sassafras officinale Sassafras (Sassafras officinale) is a perennial deciduous tree or shrub of the family Lauraceae. It was probably introduced to Europe from Florida. Their range extends along the eastern United States, from Canada to Florida, and west to Mexico. The tree has a strong scent of root beer... sassafras, while in See also Maple computer algebra system. species Acer campestre - Field Maple Acer ginnala - Amur Maple Acer griseum - Paperbark Maple Acer japonicum - Fullmoon Maple Acer macrophyllum - Bigleaf Maple Acer micranthum - Garden Maple Acer negundo - Manitoba Maple Acer palmatum - Japanese Maple Acer platanoides - Norway Maple Acer pseudoplatanus - Sycamore Maple Acer rubrum - Red... maple, Species Many, see text. An ash can be any of three different tree genera from three very distinct families (see end of page for disambiguation), but originally and most commonly refers to trees of the genus Fraxinus in the olive family Oleaceae. The ashes are usually medium to large trees... ash, For other meanings of Hickory please see Hickory (disambiguation). Species See text Hickory is a tree of the genus Carya (which also includes Pecan). The genus includes about 25 species of deciduous trees with pinnately compound leaves and large nuts. All but one of the species are native to North... hickory, Species About 60-70 species including: Celtis australis - European Hackberry Celtis bungeana Bunges Hackberry Celtis caucasica - Caucasian Hackberry Celtis labilis - Hubei Hackberry Celtis koraiensis - Korean Hackberry Celtis jessoensis - Japanese Hackberry Celtis laevigata - Southern Hackberry Celtis occidentalis - Common hackberry Celtis reticulata - Netleaf hackberry Celtis sinensis - Chinese Hackberry Celtis tenuifolia - Georgia... hackberry, For the beech tree, see below. Beech is also the name of an aircraft manufacturer that was purchased by Raytheon. Species Fagus crenata - Japanese beech Fagus engleriana - Chinese beech Fagus grandifolia - American beech Fagus japonica - Japanese blue beech Fagus longipetiolata Fagus lucida Fagus mexicana - Mexican beech or Haya Fagus orientalis... beech, and This article deals with the tree; for the e-mail client see Pine email client Species About 115. Pines are coniferous trees of the genus Pinus, in the family Pinaceae. There are about 115 species of pine, although different authors accept anything from 105 to 125 species. Distribution Pines are... pine, thick sapwood is the rule.

There is no definite relation between the annual rings of growth and the amount of sapwood. Within the same species the cross-sectional area of the sapwood is very roughly proportional to the size of the crown of the tree. If the rings are narrow, more of them are required than where they are wide. As the tree gets larger, the sapwood must necessarily become thinner or increase materially in volume. Sapwood is thicker in the upper portion of the trunk of a tree than near the base, because the age and the diameter of the upper sections are less.

When a tree is very young it is covered with limbs almost, if not entirely, to the ground, but as it grows older some or all of them will eventually die and be broken off. Subsequent growth of wood may completely conceal the stubs which will however remain as knots. No matter how smooth and clear a log is on the outside, it is more or less knotty near the middle. Consequently the sapwood of an old tree, and particularly of a forest-grown tree, will be freer from knots than the heartwood. Since in most uses of wood, knots are defects that weaken the timber and interfere with its ease of working and other properties, it follows that sapwood, because of its position in the tree, may have certain advantages over heartwood.

It is remarkable that the inner heartwood of old trees remains as sound as it usually does, since in many cases it is hundreds of years, and in a few instances thousands of years, old. Every broken limb or root, or deep wound from fire, insects, or falling timber, may afford an entrance for decay, which, once started, may penetrate to all parts of the trunk. The larvae of many insects bore into the trees and their tunnels remain indefinitely as sources of weakness. Whatever advantages, however, that sapwood may have in this connection are due solely to its relative age and position.

If a tree grows all its life in the open and the conditions of For the heavy metal band see Soil (band) Soil is the layer of minerals and organic matter, in thickness from centimetres to a metre or more, on the land surface. Its main components are mineral matter, organic matter, moisture, and air. Soils differ in the ratio of these components. Modern... soil and site remain unchanged, it will make its most rapid growth in youth, and gradually decline. The annual rings of growth are for many years quite wide, but later they become narrower and narrower. Since each succeeding ring is laid down on the outside of the wood previously formed, it follows that unless a tree materially increases its production of wood from year to year, the rings must necessarily become thinner as the trunk gets wider. As a tree reaches maturity its crown becomes more open and the annual wood production is lessened, thereby reducing still more the width of the growth rings. In the case of forest-grown trees so much depends upon the competition of the trees in their struggle for light and nourishment that periods of rapid and slow growth may alternate. Some trees, such as southern This article is about oaks (Quercus). The Australian tree known as desert-oak is unrelated, and instead belongs to the genus Allocasuarina. OAK is also the three-letter IATA airport code for Oakland International Airport in Oakland, California USA. See also Oak, Nebraska, USA. Species See List of Quercus species... oaks, maintain the same width of ring for hundreds of years. Upon the whole, however, as a tree gets larger in diameter the width of the growth rings decreases.

There may be decided differences in the grain of heartwood and sapwood cut from a large tree, particularly one that is mature. In some trees, the wood laid on late in the life of a tree is softer, lighter, weaker, and more even-textured than that produced earlier, but in other species, the reverse applies. In a large log the sapwood, because of the time in the life of the tree when it was grown, may be inferior in In materials science, hardness is the characteristic of a solid material expressing its resistance to permament deformation. There are three principal operational definitions of hardness: Scratch hardness Indentation hardness Rebound, dynamic or absolute hardness Scratch hardness In mineralogy, hardness commonly refers to a materials ability to penetrate softer materials... hardness, Strength of materials is the scientific area of applied mechanics for the study of the strength of engineering materials and their mechanical behaviour in general (such as stress, deformation, strain and stress-strain relations). Strength is considered in terms of compressive strength, tensile strength, and shear strength, namely the limit... strength, and toughness to equally sound heartwood from the same log.

Color

In species which show a distinct difference between heartwood and sapwood the natural color of heartwood is usually darker than that of the sapwood, and very frequently the contrast is conspicuous. This is produced by deposits in the heartwood of various materials resulting from the process of growth, increased possibly by The most fundamental reactions in chemistry are the redox processes. The term redox process accounts for all processes in which atoms have their oxidation number (oxidation state) changed. This can be a simple redox process, such as the combustion of carbon by oxygen to yield carbon dioxide, it could be... oxidation and other chemical changes, which usually have little or no appreciable effect on the mechanical properties of the wood. Some experiments on very resinous Binomial name Pinus palustris Mill. The Longleaf Pine (Pinus palustris) is a pine native to the southeast United States, found along the coastal plain from eastern Texas to southeast Virginia. It reaches a height of 30-35 m (to 47 m in the past) (100-115 (154) feet) and a... Longleaf Pine specimens, however, indicate an increase in strength. This is due to the Resin is a hydrocarbon secretion formed in special resin canals of many plants, from many of which (for example, coniferous trees) it is exuded in soft drops from wounds, hardening into solid masses in the air. It may be obtained by making incisions in the bark or wood of the... resin which increases the strength when dry. Such resin-saturated heartwood is called "fat lighter". Structures built of fat lighter are almost impervious to rot and termites; however they are very flammable. Stumps of old longleaf pines are often dug, split into small pieces and sold as kindling for fires. Stumps thus dug may actually a century or more since being cut. Species About 35; see text. Spruce refers to trees of the Genus Picea, a genus of about 35 species of coniferous evergreen trees in the Family Pinaceae, found in the northern temperate and boreal regions of the earth. Spruces are large trees, from 20-60 (-95) m tall when mature... Spruce impregnated with crude resin and dried is also greatly increased in strength thereby.

Coast Redwood wood - photo User:MPF File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. Click on date to download the file or see the image uploaded on that date. (del) (cur) 17:57, 5 Nov 2004 . . MPF (48036...

The wood of Binomial name Sequoia sempervirens (D. Don) Endl. The Coast Redwood or California Redwood (Sequoia sempervirens) is an evergreen, long-lived, monoecious tree in the family Cupressaceae. It is the tallest tree in the world, reaching up to 112 m in height, and 7 m diameter at the base. The crown... Coast Redwood is distinctively red in colour

Since the late wood of a growth ring is usually darker in color than the early wood, this fact may be used in judging the density, and therefore the hardness and strength of the material. This is particularly the case with coniferous woods. In ring-porous woods the vessels of the early wood not infrequently appear on a finished surface as darker than the denser late wood, though on cross sections of heartwood the reverse is commonly true. Except in the manner just stated the color of wood is no indication of strength.

Abnormal discoloration of wood often denotes a diseased condition, indicating unsoundness. The black check in western Species T. canadensis Eastern Hemlock T. caroliniana Carolina Hemlock T. chinensis Taiwan Hemlock T. diversifolia Northern Japanese Hemlock T. dumosa Himalayan Hemlock T. forrestii Forrests Hemlock T. heterophylla Western Hemlock T. mertensiana Mountain Hemlock T. sieboldii Southern Japanese Hemlock Tsuga is a genus of conifers in the family Pinaceae... hemlock is the result of insect attacks. The reddish-brown streaks so common in For other meanings of Hickory please see Hickory (disambiguation). Species See text Hickory is a tree of the genus Carya (which also includes Pecan). The genus includes about 25 species of deciduous trees with pinnately compound leaves and large nuts. All but one of the species are native to North... hickory and certain other woods are mostly the result of injury by birds. The discoloration is merely an indication of an injury, and in all probability does not of itself affect the properties of the wood. Certain rot-producing Divisions Chytridiomycota Zygomycota Ascomycota Basidiomycota The Fungi (singular: fungus) are a large group of organisms ranked as a kingdom within the Domain Eukaryota. Fungi occur in all environments on the planet and include important decomposers and parasites. Parasitic fungi infect animals, including humans, other mammals, birds, and insects, with consequences... fungi impart to wood characteristic colors which thus become symptomatic of weakness. Ordinary sap-staining is due to fungous growth, but does not necessarily produce a weakening effect.

Structure

Wood can be formed into straight planks and made into a Beech is a typical temperate zone hardwood The term hardwood designates wood from angiosperm trees. Hardwood contrasts with softwood, which comes from gymnosperm (coniferous) trees. They are in general of higher density and hardness, but there is considerable variation in actual wood hardness in both groups, with a large amount... hardwood This article is about the floor of a room or building. In mathematics, see floor function. In finance, see interest rate floor A hardwood floor (parquet) is a popular feature in many houses. In architecture, a floor is generally the lower horizontal surface of a room, but specially employed for... floor ( The parquet in some countries, including France, is the prosecution service. The parquet général is the prosecution service of a cour dappel or the Cour de Cassation. The word literally means wooden floor; this is because, as opposed to the judges, who sit on an elevated platform... parquet).

A tree increases in For the geometric term, see diameter. Diameter is an Authentication, Authorization and Accounting (AAA) protocol for applications such as network access or IP mobility. Its intended to work in both local and roaming situations. The name is a pun on the RADIUS protocol, which is the predecessor (a diameter... diameter by the formation, between the old wood and the inner bark, of new woody layers which envelop the entire stem, living branches, and roots. Under ordinary conditions one layer is formed each year and in Cross section may refer to the following In geometry, Cross section is the intersection of a 3-dimensional body with a plane. In physics, Cross section represents the probability of an interaction event between two particles. This is a disambiguation page — a navigational aid which lists other pages that... cross section as on the end of a log they appear as rings, often spoken of as Pinus taeda Cross section showing annual rings Cheraw, South Carolina Dendrochronology or tree-ring dating is the method of scientific dating based on the analysis of tree ring patterns. This technique was invented and developed during the 20th century originally by A.E. Douglass, the founder of the Laboratory of... annual rings. These growth layers are made up of wood cells of various kinds, but for the most part fibrous. In Orders & Families Cordaitales † Pinales Pinaceae - Pine family Araucariaceae - Araucaria family Podocarpaceae - Yellow-wood family Sciadopityaceae - Umbrella-pine family Cupressaceae - Cypress family Cephalotaxaceae - Plum-yew family Taxaceae - Yew family Vojnovskyales † Voltziales † The conifers... coniferous or Categories: Stub | Wood ... softwood species the wood cells are mostly of one kind, Tracheids are long tubular cells in the wooden parts of plants. Their function is to conduct water from the roots to the upper parts of the plants. Tracheids are located in the xylem, along with wood vessels. They are the most important water-conducting vessels in seedless vascular plants and... tracheids, and as a result the material is much more uniform in structure than that of most Beech is a typical temperate zone hardwood The term hardwood designates wood from angiosperm trees. Hardwood contrasts with softwood, which comes from gymnosperm (coniferous) trees. They are in general of higher density and hardness, but there is considerable variation in actual wood hardness in both groups, with a large amount... hardwoods. There are no Vessel can refer to any of the following: Objects Vessel (French vaissel, from a rare Latin vascellum, diminuitive of vas, vase, or urn), a word of somewhat wide application for many objects, the meaning common to them being capacity to hold or contain something. Thus it is a general term... vessels ("pores") in coniferous wood such as one sees so prominently in This article is about oaks (Quercus). The Australian tree known as desert-oak is unrelated, and instead belongs to the genus Allocasuarina. OAK is also the three-letter IATA airport code for Oakland International Airport in Oakland, California USA. See also Oak, Nebraska, USA. Species See List of Quercus species... oak and Species Many, see text. An ash can be any of three different tree genera from three very distinct families (see end of page for disambiguation), but originally and most commonly refers to trees of the genus Fraxinus in the olive family Oleaceae. The ashes are usually medium to large trees... ash, for example.

Each growth ring is made up of two more or less well-defined parts. That originally nearest the centre of the tree is more open textured and almost invariably lighter in color than that near the outer portion of the ring. The inner portion was formed early in the season, when growth was comparatively rapid and is known as early wood or spring wood; the outer portion is the late wood or summer wood, being produced in the Summer is one of the four temperate seasons. It is associated with hot and often dry weather. In many countries it is the time of school and university holidays. Different definitions of the start and end days exist. In astronomy, summer begins with the summer solstice (around 21 June in... summer. In There are three main subgenera of Pinus, the subgenus Strobus (White pines or soft pines), the subgenus Ducampopinus (Pinyon, Bristlecone and Lacebark pines), and the subgenus Pinus (Typical pines, or yellow or hard pines). This classification into the three subgenera is based on cone, seed and leaf characters: Subgenus Strobus... white pines there is not much contrast in the different parts of the ring, and as a result the wood is very uniform in texture and is easy to work. In There are three main subgenera of Pinus, the subgenus Strobus (White pines or soft pines), the subgenus Ducampopinus (Pinyon, Bristlecone and Lacebark pines), and the subgenus Pinus (Typical pines, or yellow or hard pines). This classification into the three subgenera is based on cone, seed and leaf characters: Subgenus Strobus... hard pines, on the other hand, the late wood is very dense and is deep-colored, presenting a very decided contrast to the soft, straw-colored early wood. In ring-porous woods each season's growth is always well defined, because the large pores of the spring abut on the denser tissue of the fall before. In the diffuse-porous woods, the demarcation between rings is not always so clear and in some cases is almost (if not entirely) invisible to the unaided eye.

The structure of the hardwoods is more complex. They are more or less filled with vessels: in some cases ( This article is about oaks (Quercus). The Australian tree known as desert-oak is unrelated, and instead belongs to the genus Allocasuarina. OAK is also the three-letter IATA airport code for Oakland International Airport in Oakland, California USA. See also Oak, Nebraska, USA. Species See List of Quercus species... oak, This article is about the chestnut plant in the genus Castanea. The name horse-chestnut is commonly applied to several species in the unrelated genus Aesculus (family Sapindaceae). Chestnut is also used to describe a certain colour of coat in horses that resembles the colour of the chestnut nut. Species... chestnut, Species Many, see text. An ash can be any of three different tree genera from three very distinct families (see end of page for disambiguation), but originally and most commonly refers to trees of the genus Fraxinus in the olive family Oleaceae. The ashes are usually medium to large trees... ash) quite large and distinct, in others ( Buckeye is a name used for several species of plants in the genus Aesculus, which see for details, and also the related Mexican Buckeye (genus Ungnadia). A buckeye is often thought to bring good luck. There is also a place called Buckeye, Arizona in the United States of America. The... buckeye, This article is about woody plants of the genus Populus. The yellow poplar or tulip poplar is not a poplar, but is the Tulip-tree. For the place see Poplar, London. Species Many, see text Populus is a genus of trees which includes the cottonwoods, poplars, and aspens, all of... poplar, Species About 350, including: Salix alba - White Willow Salix amygdaloides - Peachleaf Willow Salix arbuscula - Mountain Willow Salix aurita - Eared Willow Salix babylonica - Peking Willow Salix caprea- Goat Willow Salix caroliniana - Coastal Plain Willow Salix cinerea - Grey Sallow Salix fragilis - Crack Willow Salix herbacea - Dwarf Willow Salix lanata - Woolly Willow Salix... willow) too small to be seen plainly without a small hand lens. In discussing such woods it is customary to divide them into two large classes, ring-porous and diffuse-porous. In ring-porous species, such as Species Many, see text. An ash can be any of three different tree genera from three very distinct families (see end of page for disambiguation), but originally and most commonly refers to trees of the genus Fraxinus in the olive family Oleaceae. The ashes are usually medium to large trees... ash, Binomial name Robinia pseudoacacia Black locust (Robinia pseudoacacia) is a tree in the subfamily Faboideae of the pea family Fabaceae. It is native to eastern North America from northeast Texas to New York, and widely planted and naturalised elsewhere in the rest of temperate North America, Europe and Asia. Similar... black locust, For the historical incident involving a ship of this name, see Catalpa rescue. Species 11 species, including: Catalpa bignonioides Catalpa bungei Catalpa fargesii Catalpa longissima Catalpa ovata Catalpa punctata Catalpa speciosa Catalpa tibetica Catalpa (Catalpa), also spelled Catawba, is a genus of mostly deciduous trees of the United States, West... catalpa, This article is about the chestnut plant in the genus Castanea. The name horse-chestnut is commonly applied to several species in the unrelated genus Aesculus (family Sapindaceae). Chestnut is also used to describe a certain colour of coat in horses that resembles the colour of the chestnut nut. Species... chestnut, Species See text. Elms are deciduous trees of the genus Ulmus, family Rosales. They have alternate, simple, single- or doubly-serrate leaves, usually with asymmetric bases, often rough with fine bristles. The fruit is a round samara. There are between 20 to 45 species of elm; the ambiguity in the... elm, For other meanings of Hickory please see Hickory (disambiguation). Species See text Hickory is a tree of the genus Carya (which also includes Pecan). The genus includes about 25 species of deciduous trees with pinnately compound leaves and large nuts. All but one of the species are native to North... hickory, Species Morus alba - White Mulberry Morus australis - Chinese Mulberry Morus indica - Indian Mulberry Morus microphylla - Texas Mulberry Morus nigra - Black Mulberry Morus rubra - Red Mulberry Morus serrata - Himalayan Mulberry For other meanings, see Mulberry (disambiguation). Mulberry refers both to the mulberry tree and to the fruit of that tree. It... mulberry, and This article is about oaks (Quercus). The Australian tree known as desert-oak is unrelated, and instead belongs to the genus Allocasuarina. OAK is also the three-letter IATA airport code for Oakland International Airport in Oakland, California USA. See also Oak, Nebraska, USA. Species See List of Quercus species... oak, the larger vessels or pores (as cross sections of vessels are called) are localized in the part of the growth ring formed in spring, thus forming a region of more or less open and porous tissue. The rest of the ring, produced in summer, is made up of smaller vessels and a much greater proportion of wood fibres. These fibres are the elements which give strength and toughness to wood, while the vessels are a source of weakness.

In diffuse-porous woods the pores are scattered throughout the growth ring instead of being collected in a band or row. Examples of this kind of wood are Basswood is the common name of timbers of Tilia species. It is derived from bast, an Old English word for the fibrous inner bark of the tree. Most species have soft, easily worked wood, somewhat similar to balsa wood and often used for model building and intricate carving, and for... basswood, Species many species see text and classification Birch is the name of any tree of the genus Betula, in the family Betulaceae, closely related to the beech/oak family, Fagaceae. These are generally small to medium-size trees or shrubs, mostly of northern temperate climates. The simple leaves may be... birch, Buckeye is a name used for several species of plants in the genus Aesculus, which see for details, and also the related Mexican Buckeye (genus Ungnadia). A buckeye is often thought to bring good luck. There is also a place called Buckeye, Arizona in the United States of America. The... buckeye, See also Maple computer algebra system. species Acer campestre - Field Maple Acer ginnala - Amur Maple Acer griseum - Paperbark Maple Acer japonicum - Fullmoon Maple Acer macrophyllum - Bigleaf Maple Acer micranthum - Garden Maple Acer negundo - Manitoba Maple Acer palmatum - Japanese Maple Acer platanoides - Norway Maple Acer pseudoplatanus - Sycamore Maple Acer rubrum - Red... maple, This article is about woody plants of the genus Populus. The yellow poplar or tulip poplar is not a poplar, but is the Tulip-tree. For the place see Poplar, London. Species Many, see text Populus is a genus of trees which includes the cottonwoods, poplars, and aspens, all of... poplar, and Species About 350, including: Salix alba - White Willow Salix amygdaloides - Peachleaf Willow Salix arbuscula - Mountain Willow Salix aurita - Eared Willow Salix babylonica - Peking Willow Salix caprea- Goat Willow Salix caroliniana - Coastal Plain Willow Salix cinerea - Grey Sallow Salix fragilis - Crack Willow Salix herbacea - Dwarf Willow Salix lanata - Woolly Willow Salix... willow. Some species, such as This article is about the walnut tree. See also Walnut, California or Walnut, Illinois. Species See text The walnuts (genus Juglans) are plants in the walnut family Juglandaceae. They are deciduous trees, 10-40m tall, with pinnate leaves 20-90cm long, with 5-25 leaflets; the shoots have chambered pith... walnut and A cherry is both a tree and its fleshy fruit, a type known as a drupe with a single hard pit enclosing the seed. The cherry belongs to the family Rosaceae, genus Prunus (along with almonds, peaches, plums, and apricots). Sweet and sour cherries are different species, P. avium and... cherry, are on the border between the two classes, forming an intermediate group.

If a heavy piece of pine is compared with a light specimen it will be seen at once that the heavier one contains a larger proportion of late wood than the other, and is therefore considerably darker. The late wood of all species is denser than that formed early in the season, hence the greater the proportion of late wood the greater the density and strength. When examined under a microscope the cells of the late wood are seen to be very thick-walled and with very small cavities, while those formed first in the season have thin walls and large cavities. The strength is in the walls, not the cavities. In choosing a piece of pine where strength or stiffness is the important consideration, the principal thing to observe is the comparative amounts of early and late wood. The width of ring is not nearly so important as the proportion of the late wood in the ring.

It is not only the proportion of late wood, but also its quality, that counts. In specimens that show a very large proportion of late wood it may be noticeably more porous and weigh considerably less than the late wood in pieces that contain but little. One can judge comparative density, and therefore to some extent weight and strength, by visual inspection.

This is a file from the Wikimedia Commons, a repository of free content hosted by the Wikimedia Foundation. Please see its image description page on the Commons. File links The following pages link to this file: Wood Branch ...

The twisty branch of a Alternate meaning: Lilac (color) Species About 20-25 species; see text. *Some botanists include the Oleaceae in the order Lamiales. Lilacs (Syringa) are a genus of plants, in the family Oleaceae, native to Europe and Asia. Lilacs range in size from large shrubs to small trees, 2-10 m tall... Lilac tree

No satisfactory explanation can as yet be given for the real causes underlying the formation of early and late wood. Several factors may be involved. In conifers, at least, rate of growth alone does not determine the proportion of the two portions of the ring, for in some cases the wood of slow growth is very hard and heavy, while in others the opposite is true. The quality of the site where the tree grows undoubtedly affects the character of the wood formed, though it is not possible to formulate a rule governing it. In general, however, it may be said that where strength or ease of working is essential, woods of moderate to slow growth should be chosen. But in choosing a particular specimen it is not the width of ring, but the proportion and character of the late wood which should govern.

In the case of the ring-porous hardwoods there seems to exist a pretty definite relation between the rate of growth of timber and its properties. This may be briefly summed up in the general statement that the more rapid the growth or the wider the rings of growth, the heavier, harder, stronger, and stiffer the wood. This, it must be remembered, applies only to ring-porous woods such as oak, ash, hickory, and others of the same group, and is, of course, subject to some exceptions and limitations.

In ring-porous woods of good growth it is usually the middle portion of the ring in which the thick-walled, strength-giving fibres are most abundant. As the breadth of ring diminishes, this middle portion is reduced so that very slow growth produces comparatively light, porous wood composed of thin-walled vessels and wood parenchyma. In good oak these large vessels of the early wood occupy from 6 to 10 per cent of the volume of the log, while in inferior material they may make up 25 per cent or more. The late wood of good oak, except for A radial is a line drawn along a vector. A radial pattern is one that appears to radiate from a point, like the spokes from the hub of a wheel. In radio, evenly-spaced points along evenly-spaced radials on a map are used to determine average elevation above mean... radial grayish patches of small pores, is dark colored and firm, and consists of thick-walled fibres which form one-half or more of the wood. In inferior oak, such fibre areas are much reduced both in quantity and quality. Such variation is very largely the result of rate of growth.

Wide-ringed wood is often called "second-growth", because the growth of the young timber in open stands after the old trees have been removed is more rapid than in trees in the This article is about forests as a massing of trees. For other uses of the word, see Forest (disambiguation). A dense growth of softwoods (a forest) in the Sierra Nevada Range of Northern California A forest is an area with a high density of trees (or, historically, an area set... forest, and in the manufacture of articles where strength is an important consideration such "second-growth" hardwood material is preferred. This is particularly the case in the choice of hickory for handles and A spoke is one of some number of rods radiating from the center of a wheel (the hub where the axle connects), connecting the hub with the round traction surface. Spokes can be made of wood or metal. Some types of wheel have removable spokes which can be replaced individually... spokes. Here not only strength, but toughness and resilience are important. The results of a series of tests on hickory by the U.S. Forest Service show that:

The effect of rate of growth on the qualities of chestnut wood is summarized by the same authority as follows:

In diffuse-porous woods, as has been stated, the vessels or pores are scattered throughout the ring instead of collected in the early wood. The effect of rate of growth is, therefore, not the same as in the ring-porous woods, approaching more nearly the conditions in the Orders & Families Cordaitales † Pinales Pinaceae - Pine family Araucariaceae - Araucaria family Podocarpaceae - Yellow-wood family Sciadopityaceae - Umbrella-pine family Cupressaceae - Cypress family Cephalotaxaceae - Plum-yew family Taxaceae - Yew family Vojnovskyales † Voltziales † The conifers... conifers. In general it may be stated that such woods of medium growth afford stronger material than when very rapidly or very slowly grown. In many uses of wood, strength is not the main consideration. If ease of working is prized, wood should be chosen with regard to its uniformity of texture and straightness of grain, which will in most cases occur when there is little contrast between the late wood of one season's growth and the early wood of the next.

Water content

Drinking water This article focuses on water as we experience it every day. The water (molecule) article describes the water chemical and physical properties from a scientific and technical perspective. Water (from Low German or Old Saxon) is an abundant substance on Earth. It exists in many places and forms... Water occurs in living wood in three conditions, namely: (1) in the A cell wall is a more or less solid layer surrounding a cell. They are found in bacteria, archea, fungi, plants, and algae. Animals and most other protists have cell membranes without surrounding cell walls. When a cell wall is removed using cell wall degrading enzymes, the plasma membrane surrounded... cell walls, (2) in the Protoplasm is the substance inside the membrane of a living cell. At the simplest level, it is divisible into cytoplasm and the nucleus. It is also sometimes termed bioplasm (Beale; meaning the essential substance of living matter within a cell) and distinct from non-living cell components lumped under ergastic... protoplasmic contents of the Cells in culture, stained for keratin The cell is the structural and functional unit of all living organisms. Some organisms, such as bacteria, are unicellular, consisting of a single cell. Other organisms, such as humans, are multicellular, (humans have an estimated 100,000 billion = 1014 cells). The cell theory, first... cells, and (3) as free water in the cell cavities and spaces. In heartwood it occurs only in the first and last forms. Wood that is thoroughly air-dried retains from 8-16% of water in the cell walls, and none, or practically none, in the other forms. Even oven-dried wood retains a small percentage of moisture, but for all except chemical purposes, may be considered absolutely dry.

The general effect of the water content upon the wood substance is to render it softer and more pliable. A similar effect of common observation is in the softening action of water on Piece of paper Paper is a thin, flat material produced by the compression of fibres. The fibers used are usually natural and based upon cellulose. The most common material is wood pulp from pulpwood (largely softwood) trees such as spruces, but other vegetable fiber materials including cotton, linen, and hemp... paper or A variety of fabric. From the left: evenweave cotton, velvet, printed cotton, calico, felt, satin, silk, hessian, polycotton. Cloth or fabric is a flexible artificial material made up of a network of natural or artificial fibres (thread or yarn) formed by weaving or knitting (textiles), or pressed into felt. Cloth... cloth. Within certain limits the greater the water content the greater its softening effect.

Drying produces a decided increase in the strength of wood, particularly in small specimens. An extreme example is the case of a completely dry Species About 35; see text. Spruce refers to trees of the Genus Picea, a genus of about 35 species of coniferous evergreen trees in the Family Pinaceae, found in the northern temperate and boreal regions of the earth. Spruces are large trees, from 20-60 (-95) m tall when mature... spruce block 5 cm in section, which will sustain a permanent load four times as great as that which a green block of the same size will support.

The greatest increase due to drying is in the ultimate crushing strength, and strength at The tensile strength of a material is the maximum amount of tensile stress that it can be subjected to before it breaks. Tensile strength is an important concept in engineering, especially in the fields of material science, mechanical engineering and structural engineering. Once past the elastic limit, the material will... elastic limit in endwise compression; these are followed by the modulus of rupture, and stress at elastic limit in cross-bending, while the In solid mechanics, Youngs modulus (also known as the modulus of elasticity or elastic modulus) is a measure of the Stiffness of a given material. It is defined as the limit for small strains of the rate of change of stress with strain. This can be experimentally determined from... modulus of elasticity is least affected.

Uses

Photo by Quadell. Woodcarving by Donald Ellis Waddell, Jr. File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. Click on date to download the file or see the image uploaded on that date. (del) (cur) 21:58, 3 Oct...

An artist is someone who employs creative talent to produce works of art. The term may be used in connection with any career, often a branch of the arts—for example music, literature, and theatre—most commonly it refers to an individual who practises the visual arts or... Artists can use Artists can use woodworking to create delicate sculptures. Woodworking is the process of building, making or carving something using wood. History Along with stone, mud, and animal parts, wood was certainly one of the first materials worked by primitive man. Indeed, the development of civilization was closely tied to the... woodworking to create delicate Sculptor redirects here. You may also be looking for Sculptor (constellation). Western sculpture was first perfected in Greece Sculpture is any three-dimensional form created as an artistic expression. Sculpting is the art of assembling or shaping an object. It may be of any size and of any suitable material... sculptures.

Wood has many uses. Traditionally, wood has been used as the primary material in the construction of Houses in Fishpool Street, St Albans, England For other meanings of the word house, see House (disambiguation). A house in its most general sense is a human-built dwelling with enclosing walls and a roof. It provides shelter against precipitation, wind, heat, cold and intruding humans and animals. When occupied... houses and other buildings. See also Wikimedia Commons has multimedia related to: Bricks Masonry Brickwork Ceramics Fire brick In role-playing games, a brick is a character whose main useful skill is being able to take a great deal of damage (usually physical damage) and act as a shield for weaker allies. These characters... Brick was then used, and now This article is about the construction material. For the philosophical term, see Concrete (philosophy). For the comic book, see Concrete (comics). Placing a concrete floor for a commercial building In construction, concrete is a composite building material made from the combination of aggregate and cement binder. The most common form... concrete is also used.

Much Furniture is the collective term for the movable objects which support the human body (seating furniture and beds), provide storage, and hold objects on horizontal surfaces above the ground. Storage furniture is used to hold or contain smaller objects such as tools, books, and household goods. Furniture can be a... furniture is produced from wood, mostly from hardwoods such as mahogany.

Perhaps the most important use of wood in terms of Human beings are defined variously in biological, spiritual, and cultural terms, or in combinations thereof. Biologists classify human beings as Homo sapiens (Latin for knowing man), a primate species of mammal with a highly developed brain, belonging to the family of great apes, along with chimpanzees, bonobos, gorillas, and orangutans... human development was the creation of FIRE can stand for Foundation for Individual Rights in Education Fully Integrated Robotised Engine, an engine from Fiat. This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. If an article link referred you here, you might want to go... fire. Fire wood is still used as a Wood burning is the largest current use of biomass derived energy. Wood can be used as a solid fuel for cooking or heating, or occasionally for steam engines. The use of wood as a fuel source for home heat is as old as civilization itself. Historically, it was limited in... fuel to provide Combustion or burning is an exothermic reaction between a substance and a gas to release heat. Combustion normally occurs in oxygen (often in the form of gaseous O2) to form oxides, However, combustion can also take place in other gases like chlorine. The products of such reactions usually include water... combustion with which to heat homes in many areas. If the wood is burnt in modern stoves and taken from forests which are regrown to replace the wood burnt then this can be a relatively environmental way of providing energy.

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