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Wir sind ein Baumhaushotel direkt im Wolfcenter Dörverden. Von unseren 5m hohen Baumhäusern kann man Wölfe in Ihren Gehegen erleben. Unsere. Das luxuriöse Abenteuer in 5 und 8 m Höhe und ein unvergessliches Erlebnis in Mitten von Wölfen. Die Räumlichkeiten unserer zwei Baumhaushotels sind voll. Das Tree Inn - Das Baumhaushotel liegt in Dörverden und bietet 4 Unterkünfte mit eigener Terrasse. scenes of dancing by the sacred tree. It may, on the other hand, be a condhshell, but the drum is more commonly associated with tree and bird. If it is a drum. Startseite von tree of life Baumbestattungen. Wir begrüßen Sie recht herzlich auf unseren Seiten. Wir wollen Ihnen Mut machen, sich mit einer zukünftigen.
Terminology We will now introduce a number of formalisms that lead us to a formal description of a game tree. This gives us the background to define the. Startseite von tree of life Baumbestattungen. Wir begrüßen Sie recht herzlich auf unseren Seiten. Wir wollen Ihnen Mut machen, sich mit einer zukünftigen. Wir sind ein Baumhaushotel direkt im Wolfcenter Dörverden. Von unseren 5m hohen Baumhäusern kann man Wölfe in Ihren Gehegen erleben. Unsere.
Tree In VideoENG SUB - 《Tree In The River》 EP03-- Starring: Mike He,Gillian Chung,Ray Chang,Sonia Sui
This is dendrochronology. Very few tropical trees can be accurately dated in this manner. The roots of a tree are almost always underground, usually in a ball shaped region centered under the trunk, and extending no deeper than the tree is high.
Roots can also be above ground, or deep underground. Some roots are short, some are meters long. Roots provide support for the parts above ground, holding the tree upright, and keeping it from falling over in high wind.
Roots take in water , and nutrients , from the soil. Without help from fungus for better uptake of nutrients, trees would be small or would die.
Most trees have a favorite species of fungus that they associate with for this purpose. Above ground, the trunk gives height to the leaf-bearing branches, competing with other plant species for sunlight.
In all trees the shape of the branches improves the exposure of the leaves to sunlight. Branches start at the trunk, big and thick, and get progressively smaller the farther they grow from the trunk.
Branches themselves split into smaller branches, sometime very many times, until at the end they are quite small. The small ends are called twigs.
The leaves of a tree are held by the branches. Leaves are usually held at the ends of the branches.
The, although some have leaves along the branches. The main functions of leaves are photosynthesis and gas exchange. A leaf is often flat, so it absorbs the most light, and thin, so that the sunlight can get to the green parts in the cells, which convert sunlight, carbon dioxide from the atmosphere , and water from the roots, into glucose and oxygen.
Most of a tree's biomass comes from this process. Most leaves have stomata , which open and close, and regulate carbon dioxide, oxygen, and water vapour exchange with the atmosphere.
Trees with leaves all year round are evergreens , and those that shed their leaves are deciduous. Deciduous trees and shrubs generally lose their leaves in autumn as it gets cold.
Before this happens, the leaves change colour. The leaves will grow back in spring. The word "tree" in English means a long lived plant having obvious main stem, and growing to a considerable height and size.
Thus not all trees have all the organs or parts as mentioned above. For example, most tree-like palms are not branched, and tree ferns do not produce bark.
There are also more exceptions. Based on their general shape and size, all of these are nonetheless generally regarded as trees.
Trees can vary a lot. A plant that is similar to a tree, but generally smaller, and may have multiple trunks, or have branches that arise near the ground, is called a " shrub ", or a "bush".
Since these are common English words there is no precise differentiation between shrubs and trees.
Given their small size, bonsai plants would not technically be "trees", but are indeed "trees".
Do not confuse the use of tree for a species of plant, with the size or shape of individual specimens. A spruce seedling does not fit the definition of a tree, but all spruces are trees.
A tree is a plant form that can be found in many different orders and families of plants. Trees show many growth forms , leaf type and shape, bark traits and organs.
The tree form has changed separately in classes of plants that are not related, in response to similar problems for the tree. With about , types of trees, the number of tree types in the whole world might be one fourth of all living plant types.
The earliest trees were tree ferns , horsetails and lycophytes , which grew in forests in the Carboniferous period; tree ferns still survive, but the only surviving horsetails and lycophytes are not of tree form.
Later, in the Triassic Period, conifers , ginkgos , cycads and other gymnosperms appeared, and subsequently flowering plants in the Cretaceous period.
Most species of trees today are flowering plants Angiosperms and conifers. A small group of trees growing together is called a grove or copse , and a landscape covered by a dense growth of trees is called a forest.
Several biotopes are defined largely by the trees that inhabit them; examples are rainforest and taiga see ecozones. A landscape of trees scattered or spaced across grassland usually grazed or burned over periodically is called a savanna.
A forest of great age is called old growth forest or ancient woodland in the UK. A very young tree is called a sapling. Scientists in the UK and Malaysia say they have discovered the world's tallest tropical tree measuring more than m ft high.
A coast redwood : The tallest trees in Australia are all eucalypts , of which there are more than species. The so-called 'mountain ash'.
The stoutest living single-trunk species in diameter is the African baobab : Some trees develop multiple trunks whether from an individual tree or multiple trees which grow together.
The sacred fig is a notable example of this, forming additional 'trunks' by growing adventitious roots down from the branches, which then thicken up when the root reaches the ground to form new trunks; a single sacred fig tree can have hundreds of such trunks.
The life-span of trees is determined by growth rings. These can be seen if the tree is cut down or in cores taken from the edge to the center of the tree.
Correct determination is only possible for trees which make growth rings, generally those which occur in seasonal climates.
Trees in uniform non-seasonal tropical climates are always growing and do not have distinct growth rings. It is also only possible for trees which are solid to the center of the tree; many very old trees become hollow as the dead heartwood decays away.
For some of these species, age estimates have been made on the basis of extrapolating current growth rates, but the results are usually little better than guesses or speculation.
White proposed a method of estimating the age of large and veteran trees in the United Kingdom by correlation between a tree's stem diameter, growth character and age.
Other species suspected of reaching exceptional age include European Yew Taxus baccata probably over 2, years   and western redcedar Thuja plicata.
The oldest known European yew is the Llangernyw yew in the Churchyard of Llangernyw village in North Wales which is estimated to be between 4, and 5, years old.
The earliest fossilised trees date to million years ago in the Devonian period. They have been found at an abandoned quarry in Cairo, New York.
The forest was so vast it originally stretched beyond Pennsylvania. This discovery two or three million years older than the previous oldest forest at Gilboa , also in New York State.
These most likely use diameter measured at breast height dbh , 4. A general model for any year and diameter is:. Tree climbing is an activity where one moves around in the crown of trees.
Use of a rope , helmet , and harness are the minimum requirements to ensure the safety of the climber. Other equipment can also be used depending on the experience and skill of the tree climber.
Some tree climbers take special hammocks called "Treeboats" and Portaledges with them into the tree canopies where they can enjoy a picnic or nap, or spend the night.
Tree climbing is an "on rope" activity that puts together many different tricks and gear originally derived from rock climbing and caving.
These techniques are used to climb trees for many purposes, including tree care arborists , animal rescue, recreation, sport, research, and activism.
The three big sources of tree damage are biotic from living sources , abiotic from non-living sources and deforestation cutting trees down.
Biotic sources would include insects which might bore into the tree, deer which might rub bark off the trunk, or fungi , which might attach themselves to the tree.
Abiotic sources include lightning , vehicles impacts, and construction activities. Construction activities can involve a number of damage sources, including grade changes that prevent aeration to roots, spills involving toxic chemicals such as cement or petroleum products, or severing of branches or roots.
People can damage trees also. Both damage sources can result in trees becoming dangerous, and the term "hazard trees" is commonly used by arborists, and industry groups such as power line operators.
Hazard trees are trees which due to disease or other factors are more susceptible to falling during windstorms, or having parts of the tree fall.
The process of finding the danger a tree presents is based on a process called the quantified tree risk assessment. Trees are similar to people.
The roots are, generally, an underground part of the tree, but some tree species have evolved roots that are aerial. The common purposes for aerial roots may be of two kinds, to contribute to the mechanical stability of the tree, and to obtain oxygen from air.
An instance of mechanical stability enhancement is the red mangrove that develops prop roots that loop out of the trunk and branches and descend vertically into the mud.
These brace the tree rather like angle brackets and provide stability, reducing sway in high winds. They are particularly prevalent in tropical rainforests where the soil is poor and the roots are close to the surface.
Some tree species have developed root extensions that pop out of soil, in order to get oxygen, when it is not available in the soil because of excess water.
These root extensions are called pneumatophores , and are present, among others, in black mangrove and pond cypress.
The main purpose of the trunk is to raise the leaves above the ground, enabling the tree to overtop other plants and outcompete them for light.
In the case of angiosperms and gymnosperms, the outermost layer of the trunk is the bark , mostly composed of dead cells of phellem cork.
It protects the trunk against the elements, disease, animal attack and fire. It is perforated by a large number of fine breathing pores called lenticels , through which oxygen diffuses.
Bark is continually replaced by a living layer of cells called the cork cambium or phellogen. Similarly, the bark of the silver birch Betula pendula peels off in strips.
As the tree's girth expands, newer layers of bark are larger in circumference, and the older layers develop fissures in many species. In some trees such as the pine Pinus species the bark exudes sticky resin which deters attackers whereas in rubber trees Hevea brasiliensis it is a milky latex that oozes out.
The quinine bark tree Cinchona officinalis contains bitter substances to make the bark unpalatable.
Although the bark functions as a protective barrier, it is itself attacked by boring insects such as beetles. These lay their eggs in crevices and the larvae chew their way through the cellulose tissues leaving a gallery of tunnels.
This may allow fungal spores to gain admittance and attack the tree. Dutch elm disease is caused by a fungus Ophiostoma species carried from one elm tree to another by various beetles.
The tree reacts to the growth of the fungus by blocking off the xylem tissue carrying sap upwards and the branch above, and eventually the whole tree, is deprived of nourishment and dies.
In Britain in the s, 25 million elm trees were killed by this disease. The innermost layer of bark is known as the phloem and this is involved in the transport of the sap containing the sugars made by photosynthesis to other parts of the tree.
It is a soft spongy layer of living cells, some of which are arranged end to end to form tubes. These are supported by parenchyma cells which provide padding and include fibres for strengthening the tissue.
The cells are continually dividing, creating phloem cells on the outside and wood cells known as xylem on the inside. The newly created xylem is the sapwood.
It is composed of water-conducting cells and associated cells which are often living, and is usually pale in colour. It transports water and minerals from the roots to the upper parts of the tree.
The oldest, inner part of the sapwood is progressively converted into heartwood as new sapwood is formed at the cambium.
The conductive cells of the heartwood are blocked in some species. Heartwood is usually darker in colour than the sapwood.
It is the dense central core of the trunk giving it rigidity. Three quarters of the dry mass of the xylem is cellulose , a polysaccharide , and most of the remainder is lignin, a complex polymer.
A transverse section through a tree trunk or a horizontal core will show concentric circles or lighter or darker wood — tree rings.
These are vascular rays which are thin sheets of living tissue permeating the wood. Trees do not usually grow continuously throughout the year but mostly have spurts of active expansion followed by periods of rest.
This pattern of growth is related to climatic conditions; growth normally ceases when conditions are either too cold or too dry.
In readiness for the inactive period, trees form buds to protect the meristem , the zone of active growth. Before the period of dormancy, the last few leaves produced at the tip of a twig form scales.
These are thick, small and closely wrapped and enclose the growing point in a waterproof sheath. Inside this bud there is a rudimentary stalk and neatly folded miniature leaves, ready to expand when the next growing season arrives.
Buds also form in the axils of the leaves ready to produce new side shoots. A few trees, such as the eucalyptus , have "naked buds" with no protective scales and some conifers, such as the Lawson's cypress , have no buds but instead have little pockets of meristem concealed among the scale-like leaves.
When growing conditions improve, such as the arrival of warmer weather and the longer days associated with spring in temperate regions, growth starts again.
The expanding shoot pushes its way out, shedding the scales in the process. These leave behind scars on the surface of the twig.
The whole year's growth may take place in just a few weeks. The new stem is unlignified at first and may be green and downy.
The Arecaceae palms have their leaves spirally arranged on an unbranched trunk. Primary growth is the elongation of the stems and roots.
Secondary growth consists of a progressive thickening and strengthening of the tissues as the outer layer of the epidermis is converted into bark and the cambium layer creates new phloem and xylem cells.
The bark is inelastic. If damage occurs the tree may in time become hollow. Leaves are structures specialised for photosynthesis and are arranged on the tree in such a way as to maximise their exposure to light without shading each other.
Trees have evolved leaves in a wide range of shapes and sizes, in response to environmental pressures including climate and predation.
They can be broad or needle-like, simple or compound, lobed or entire, smooth or hairy, delicate or tough, deciduous or evergreen.
The needles of coniferous trees are compact but are structurally similar to those of broad-leaved trees. They are adapted for life in environments where resources are low or water is scarce.
Frozen ground may limit water availability and conifers are often found in colder places at higher altitudes and higher latitudes than broad leaved trees.
In conifers such as fir trees, the branches hang down at an angle to the trunk, enabling them to shed snow.
In contrast, broad leaved trees in temperate regions deal with winter weather by shedding their leaves. When the days get shorter and the temperature begins to decrease, the leaves no longer make new chlorophyll and the red and yellow pigments already present in the blades become apparent.
This causes the cells at the junction of the petiole and the twig to weaken until the joint breaks and the leaf floats to the ground.
In tropical and subtropical regions, many trees keep their leaves all year round. Individual leaves may fall intermittently and be replaced by new growth but most leaves remain intact for some time.
Other tropical species and those in arid regions may shed all their leaves annually, such as at the start of the dry season.
Trees can be pollinated either by wind or by animals, mostly insects. Many angiosperm trees are insect pollinated.
Wind pollination may take advantage of increased wind speeds high above the ground. Some rely on wind, with winged or plumed seeds.
Others rely on animals, for example with edible fruits. Others again eject their seeds ballistic dispersal , or use gravity so that seeds fall and sometimes roll.
Seeds are the primary way that trees reproduce and their seeds vary greatly in size and shape. Some of the largest seeds come from trees, but the largest tree, Sequoiadendron giganteum , produces one of the smallest tree seeds.
For a tree seedling to grow into an adult tree it needs light. If seeds only fell straight to the ground, competition among the concentrated saplings and the shade of the parent would likely prevent it from flourishing.
Many seeds such as birch are small and have papery wings to aid dispersal by the wind. Ash trees and maples have larger seeds with blade shaped wings which spiral down to the ground when released.
The kapok tree has cottony threads to catch the breeze. The seeds of conifers, the largest group of gymnosperms, are enclosed in a cone and most species have seeds that are light and papery that can be blown considerable distances once free from the cone.
Fire stimulates release and germination of seeds of the jack pine , and also enriches the forest floor with wood ash and removes competing vegetation.
The flame tree Delonix regia does not rely on fire but shoots its seeds through the air when the two sides of its long pods crack apart explosively on drying.
Mangroves often grow in water and some species have propagules , which are buoyant fruits with seeds that start germinating before becoming detached from the parent tree.
Other seeds, such as apple pips and plum stones, have fleshy receptacles and smaller fruits like hawthorns have seeds enclosed in edible tissue; animals including mammals and birds eat the fruits and either discard the seeds, or swallow them so they pass through the gut to be deposited in the animal's droppings well away from the parent tree.
The germination of some seeds is improved when they are processed in this way. The single extant species of Ginkgophyta Ginkgo biloba has fleshy seeds produced at the ends of short branches on female trees,  and Gnetum , a tropical and subtropical group of gymnosperms produce seeds at the tip of a shoot axis.
The earliest trees were tree ferns , horsetails and lycophytes , which grew in forests in the Carboniferous period.
The first tree may have been Wattieza , fossils of which have been found in New York State in dating back to the Middle Devonian about million years ago.
Prior to this discovery, Archaeopteris was the earliest known tree. The gymnosperms include conifers, cycads, gnetales and ginkgos and these may have appeared as a result of a whole genome duplication event which took place about million years ago.
This is considered to be a living fossil because it is virtually unchanged from the fossilised specimens found in Triassic deposits.
During the Mesozoic to 66 million years ago the conifers flourished and became adapted to live in all the major terrestrial habitats.
Subsequently, the tree forms of flowering plants evolved during the Cretaceous period. These began to displace the conifers during the Tertiary era 66 to 2 million years ago when forests covered the globe.
In the interglacials , trees recolonised the land that had been covered by ice, only to be driven back again in the next ice age.
Trees are an important part of the terrestrial ecosystem ,  providing essential habitats including many kinds of forest for communities of organisms.
Epiphytic plants such as ferns , some mosses, liverworts, orchids and some species of parasitic plants e.
Leaves, flowers and fruits are seasonally available. On the ground underneath trees there is shade, and often there is undergrowth, leaf litter, and decaying wood that provide other habitat.
Many species of tree support their own specialised invertebrates. In their natural habitats, different species of insect have been found on the English oak Quercus robur  and species of invertebrate on the Tasmanian oak Eucalyptus obliqua.
In ecosystems such as mangrove swamps, trees play a role in developing the habitat, since the roots of the mangrove trees reduce the speed of flow of tidal currents and trap water-borne sediment, reducing the water depth and creating suitable conditions for further mangrove colonisation.
Thus mangrove swamps tend to extend seawards in suitable locations. Silviculture is the practice of controlling the establishment, growth, composition, health, and quality of forests, which are areas that have a high density of trees.
Cultivated trees are planted and tended by humans, usually because they provide food fruits or nuts , ornamental beauty, or some type of wood product that benefits people.
An area of land planted with fruit or nut trees is an orchard. Trees are the source of many of the world's best known fleshy fruits.
Apples, pears, plums, cherries and citrus are all grown commercially in temperate climates and a wide range of edible fruits are found in the tropics.
Other commercially important fruit include dates, figs and olives. Palm oil is obtained from the fruits of the oil palm Elaeis guineensis.
The fruits of the cocoa tree Theobroma cacao are used to make cocoa and chocolate and the berries of coffee trees, Coffea arabica and Coffea canephora , are processed to extract the coffee beans.
In many rural areas of the world, fruit is gathered from forest trees for consumption. These include coconuts Cocos nucifera , Brazil nuts Bertholletia excelsa , pecans Carya illinoinensis , hazel nuts Corylus , almonds Prunus dulcis , walnuts Juglans regia , pistachios Pistacia vera and many others.
They are high in nutritive value and contain high-quality protein, vitamins and minerals as well as dietary fibre.
In temperate climates there is a sudden movement of sap at the end of the winter as trees prepare to burst into growth.
In North America, the sap of the sugar maple Acer saccharum is most often used in the production of a sweet liquid, maple syrup.
The sap is harvested by drilling holes in the trunks of the trees and collecting the liquid that flows out of the inserted spigots.
It is piped to a sugarhouse where it is heated to concentrate it and improve its flavour. Similarly in northern Europe the spring rise in the sap of the silver birch Betula pendula is tapped and collected, either to be drunk fresh or fermented into an alcoholic drink.
Sweet birch sap is more dilute than maple sap; a hundred litres are required to make one litre of birch syrup.
Various parts of trees are used as spices. These include cinnamon , made from the bark of the cinnamon tree Cinnamomum zeylanicum and allspice , the dried small fruits of the pimento tree Pimenta dioica.
Nutmeg is a seed found in the fleshy fruit of the nutmeg tree Myristica fragrans and cloves are the unopened flower buds of the clove tree Syzygium aromaticum.
Many trees have flowers rich in nectar which are attractive to bees. The production of forest honey is an important industry in rural areas of the developing world where it is undertaken by small-scale beekeepers using traditional methods.
The leaves of trees are widely gathered as fodder for livestock and some can be eaten by humans but they tend to be high in tannins which makes them bitter.
Wood smoke can be used to preserve food. In the hot smoking process the food is exposed to smoke and heat in a controlled environment.
The food is ready to eat when the process is complete, having been tenderised and flavoured by the smoke it has absorbed.
The flavour of the food is enhanced but raw food requires further cooking. If it is to be preserved, meat should be cured before cold smoking.
Wood has traditionally been used for fuel, especially in rural areas. In less developed nations it may be the only fuel available and collecting firewood is often a time consuming task as it becomes necessary to travel further and further afield in the search for fuel.
In more developed countries other fuels are available and burning wood is a choice rather than a necessity. Modern wood-burning stoves are very fuel efficient and new products such as wood pellets are available to burn.
Charcoal can be made by slow pyrolysis of wood by heating it in the absence of air in a kiln. The carefully stacked branches, often oak, are burned with a very limited amount of air.
The process of converting them into charcoal takes about fifteen hours. Charcoal is used as a fuel in barbecues and by blacksmiths and has many industrial and other uses.
Timber, "trees that are grown in order to produce wood"  is cut into lumber sawn wood for use in construction. Wood has been an important, easily available material for construction since humans started building shelters.
Engineered wood products are available which bind the particles, fibres or veneers of wood together with adhesives to form composite materials.
Plastics have taken over from wood for some traditional uses. Wood is used in the construction of buildings, bridges, trackways, piles, poles for power lines, masts for boats, pit props, railway sleepers, fencing, hurdles, shuttering for concrete, pipes, scaffolding and pallets.
In housebuilding it is used in joinery, for making joists, roof trusses, roofing shingles, thatching, staircases, doors, window frames, floor boards, parquet flooring, panelling and cladding.
Wood is used to construct carts, farm implements, boats, dugout canoes and in shipbuilding. It is used for making furniture, tool handles, boxes, ladders, musical instruments, bows, weapons, matches, clothes pegs, brooms, shoes, baskets, turnery, carving, toys, pencils, rollers, cogs, wooden screws, barrels, coffins, skittles, veneers, artificial limbs, oars, skis, wooden spoons, sports equipment and wooden balls.
Wood is pulped for paper and used in the manufacture of cardboard and made into engineered wood products for use in construction such as fibreboard , hardboard , chipboard and plywood.
Besides inspiring artists down the centuries, trees have been used to create art. Living trees have been used in bonsai and in tree shaping , and both living and dead specimens have been sculpted into sometimes fantastic shapes.
The word bonsai is often used in English as an umbrella term for all miniature trees in containers or pots.
The purposes of bonsai are primarily contemplation for the viewer and the pleasant exercise of effort and ingenuity for the grower.
Bonsai can be created from nearly any perennial woody-stemmed tree or shrub species  that produces true branches and can be cultivated to remain small through pot confinement with crown and root pruning.
Some species are popular as bonsai material because they have characteristics, such as small leaves or needles, that make them appropriate for the compact visual scope of bonsai and a miniature deciduous forest can even be created using such species as Japanese maple , Japanese zelkova or hornbeam.
Tree shaping is the practice of changing living trees and other woody plants into man made shapes for art and useful structures. There are a few different methods  of shaping a tree.
There is a gradual method and there is an instant method. Tree shaping has been practised for at least several hundred years, the oldest known examples being the living root bridges built and maintained by the Khasi people of Meghalaya , India using the roots of the rubber tree Ficus elastica.
Cork is produced from the thick bark of the cork oak Quercus suber. It is harvested from the living trees about once every ten years in an environmentally sustainable industry.
The bark of other varieties of oak has traditionally been used in Europe for the tanning of hides though bark from other species of tree has been used elsewhere.
The active ingredient, tannin , is extracted and after various preliminary treatments, the skins are immersed in a series of vats containing solutions in increasing concentrations.
The tannin causes the hide to become supple, less affected by water and more resistant to bacterial attack.
At least drugs come from plant sources , many of them from the bark of trees. The papery bark of the white birch tree Betula papyrifera was used extensively by Native Americans.
Wigwams were covered by it and canoes were constructed from it. Other uses included food containers, hunting and fishing equipment, musical instruments, toys and sledges.
Trees create a visual impact in the same way as do other landscape features and give a sense of maturity and permanence to park and garden.
They are grown for the beauty of their forms, their foliage, flowers, fruit and bark and their siting is of major importance in creating a landscape.
They can be grouped informally, often surrounded by plantings of bulbs, laid out in stately avenues or used as specimen trees.
As living things, their appearance changes with the season and from year to year. Trees are often planted in town environments where they are known as street trees or amenity trees.
They can provide shade and cooling through evapotranspiration , absorb greenhouse gases and pollutants, intercept rainfall, and reduce the risk of flooding.
Scientific studies show that street trees help cities be more sustainable, and improve the physical and mental wellbeing of the citizens.
Many towns have initiated tree-planting programmes. Latex is a sticky defensive secretion that protects plants against herbivores.
Originally used to create bouncy balls and for the waterproofing of cloth, natural rubber is now mainly used in tyres for which synthetic materials have proved less durable.
This is also used as an insulator, particularly of undersea cables, and in dentistry, walking sticks and gun butts. It has now largely been replaced by synthetic materials.
Resin is another plant exudate that may have a defensive purpose. It is a viscous liquid composed mainly of volatile terpenes and is produced mostly by coniferous trees.
It is used in varnishes, for making small castings and in ten-pin bowling balls. When heated, the terpenes are driven off and the remaining product is called "rosin" and is used by stringed instrumentalists on their bows.
Some resins contain essential oils and are used in incense and aromatherapy. Fossilised resin is known as amber and was mostly formed in the Cretaceous to 66 million years ago or more recently.
The resin that oozed out of trees sometimes trapped insects or spiders and these are still visible in the interior of the amber.
The camphor tree Cinnamomum camphora produces an essential oil  and the eucalyptus tree Eucalyptus globulus is the main source of eucalyptus oil which is used in medicine, as a fragrance and in industry.
Dead trees pose a safety risk, especially during high winds and severe storms, and removing dead trees involves a financial burden, whereas the presence of healthy trees can clean the air, increase property values, and reduce the temperature of the built environment and thereby reduce building cooling costs.
During times of drought, trees can fall into water stress , which may cause a tree to become more susceptible to disease and insect problems, and ultimately may lead to a tree's death.
Irrigating trees during dry periods can reduce the risk of water stress and death. Trees have been venerated since time immemorial.
To the ancient Celts , certain trees, especially the oak , ash and thorn , held special significance  as providing fuel, building materials, ornamental objects and weaponry.
Other cultures have similarly revered trees, often linking the lives and fortunes of individuals to them or using them as oracles.
In Greek mythology , dryads were believed to be shy nymphs who inhabited trees. The Oubangui people of west Africa plant a tree when a child is born.
As the tree flourishes, so does the child but if the tree fails to thrive, the health of the child is considered at risk.
When it flowers it is time for marriage. Gifts are left at the tree periodically and when the individual dies, their spirit is believed to live on in the tree.
Trees have their roots in the ground and their trunk and branches extended towards the sky. This concept is found in many of the world's religions as a tree which links the underworld and the earth and holds up the heavens.
In Norse mythology , Yggdrasil is a central cosmic tree whose roots and branches extend to various worlds.
Various creatures live on it. Icons are placed beneath it to be worshipped, tree nymphs inhabit the branches and it grants favours to the devout who tie threads round the trunk.
Sacred groves exist in China, India, Africa and elsewhere. They are places where the deities live and where all the living things are either sacred or are companions of the gods.
Folklore lays down the supernatural penalties that will result if desecration takes place for example by the felling of trees. Because of their protected status, sacred groves may be the only relicts of ancient forest and have a biodiversity much greater than the surrounding area.
It has been named Hyperion and is The oldest living tree with a verified age is also in California. It has been dated by drilling a core sample and counting the annual rings.
It is estimated to currently be 5, years old. A little farther south, at Santa Maria del Tule , Oaxaca , Mexico, is the tree with the broadest trunk.
The tree's trunk is far from round and the exact dimensions may be misleading as the circumference includes much empty space between the large buttress roots.
Wohlleben, Peter ; Flannery, Tim F. From Wikipedia, the free encyclopedia. Perennial woody plant with elongated trunk. For other uses, see Tree disambiguation.
Further information: Forest. Main article: Root. Main article: Trunk botany. Main article: Bud. Main article: Leaf.
Further information: Plant reproduction , Pollination , and Seed dispersal. Main article: Seed. Further information: Evolutionary history of plants.
Further information: nut fruit and fruit. Main article: Wood fuel. Main articles: Wood and Timber.
Main article: Bonsai. Main article: Tree shaping. Further information: Bark botany. Main article: Ornamental trees.
Further information: Resin , Latex , and Camphor. Main article: Tree worship. Main article: List of superlative trees. Arboretum da Vinci branching rule Dendrology Dendrometry Exploding tree Fruit tree Multipurpose tree — a tree grown and managed for more than one output Tree climbing Tree house List of lists of trees.
The previous record holder was named Methuselah, with an age of 4, years measured in Bibcode : Natur.
Smartphone tour. University of Miami: John C. Gifford Arboretum. Archived from the original on 20 April Retrieved 23 September Newton Ask a Scientist.
Archived from the original on