Specific Topic 7.2 Timber

Specific Topic 7.2 Timber

1. 7.2.1 Natural Timbers - Hardwoods

   • the wood from a broadleaved tree (such as oak, ash, or beech) as distinguished from that of conifers.
   • Balsa (1)
     • very lightweight timber used chiefly for making models and rafts. Also the fast-growing tropical American tree from which this timber is obtained.
   • Beech (1)
     • a large tree with smooth grey bark, glossy leaves, and hard, pale fine-grained timber. the hard, pale fine-grained timber of the beech.noun: beechwood"a worktop in solid beech"
   • Mahongony (1)
     • Mahogany is a kind of wood—the straight-grained, reddish-brown timber of three tropical hardwood species of the genus Swietenia, indigenous to the Americas, part of the pantropical chinaberry family, Meliaceae.
   • Oak (1)
     • a large tree which bears acorns and typically has lobed deciduous leaves. Oaks are dominant in many north temperate forests and are an important source of durable timber used in building, furniture, and (formerly) ships.
   • Jelutong
     • a Malaysian tree with pale lightweight timber.
   • Birch
     • a slender hardy tree which has thin peeling bark and bears catkins. Birch trees grow chiefly in northern temperate regions and yield hard, pale, fine-grained timber.the hard fine-grained pale wood of birch trees.
   • Ash
     • Light, creamy-brown colour, open-grained used for sports equiptment

2. 7.2.2 Natural Timbers - Softwoods

   • the wood from a conifer (such as pine, fir, or spruce) as distinguished from that of broadleaved trees.
   • Larch
     • a coniferous tree with bunches of deciduous bright green needles, found in cool regions of the northern hemisphere. It is grown for its tough timber and its resin (which yields turpentine).
   • Pine (1)
     • an evergreen coniferous tree which has clusters of long needle-shaped leaves. Many kinds are grown for the soft timber, which is widely used for furniture and pulp, or for tar and turpentine.
   • Cedar (1)
     • any of a number of conifers which typically yield fragrant, durable timber, in particular: Origin

3. 7.2.3

   • Plywood (1)
     • a type of strong thin wooden board consisting of two or more layers glued and pressed together with the direction of the grain alternating.
   • Medium Density Fibreboard (1)
     • this is bits of wood dust put together by glue and water
   • Chipboard
     • material made in rigid sheets from compressed wood chips and resin, often coated or veneered, used in furniture, buildings, etc.

4. 7.2.4 Sources and origins

   • Alpine forests
     • Pine
       • Most pines have thick and scaly bark. A lot of branches arise from the same, spirally arranged points on the tree. Pines have leaves shaped like needles that remain on the trees throughout the whole year (evergreen plants). Pines reproduce via cones, conically shaped structures that contain male and female sex organs.
     • Cedar
       • Cedrus (common English name cedar) is a genus of coniferous trees in the plant family Pinaceae (subfamily Abietoideae). They are native to the mountains of the western Himalayas and the Mediterranean region, occurring at altitudes of 1,500–3,200 m in the Himalayas and 1,000–2,200 m in the Mediterranean.
     • Larch
       • Larch trees are large deciduous trees with short needles and cones. ... Native to many parts of Northern Europe and Asia as well as Northern parts of North America, larches are happiest in cold climates. They grow best in mountainous areas but tolerate any cool climate with plenty of moisture.
   • European forests
     • Oak
       • Oak belongs to the genus Quercus which comprises over 600 different species of trees. Most species of oak trees are deciduous with only couple of evergreen forms. Oak trees live on the Northern hemisphere. They can survive in various forests, including those in temperate climates, Mediterranean and tropical areas.
     • Beech
       • Beech (Fagus) is a genus of deciduous trees in the family Fagaceae, native to temperate Europe, Asia and North America. Recent classification systems of the genus recognize ten to thirteen species in two distinct subgenera, Engleriana and Fagus.
     • Ash
       • made for tool handles. Fraxinus /ˈfræksɪnəs/, English name ash, is a genus of flowering plants in the olive and lilac family, Oleaceae. It contains 45–65 species of usually medium to large trees, mostly deciduous though a few subtropical species are evergreen. The genus is widespread across much of Europe, Asia and North America.
     • Larch
   • Amazonian forests
     • Mahogany
       • has a very attractive finish. easy to work with. it can cause skin rash or breathing problem.

5. 7.2.5 Physical Characteristics

   • Knots
     • a knot in timber appears where a branch grew out of the tree: the grain swirls around the wood can be harder, so a knot can make parts of the tree harder to cut with a saw or a chisels. knots also fall out, leaving a hole, so it is good to use timber that is free of them. however knots can make trees look very appealing.  
   • Colour
     • different woods can be different colours, from the pale colours of pine to the rich, dark reddish brown iof mahogany. but trees are living organisms and thir colours will vary from tree to tree and within the tree itself. this means that when you afre buying timber it's important to remember that colour may vary from plank to plank.
   • Grain structure and density
     • timbers are split into hardwoods and softwood. hardwoods have 2 typesw of vessels, known as fibres and pores, which run the length of the tree. softwoods have only one main cell called tracheids. both have annual rings, produced

6. 7.2.6 Properties

   • Compressive strength
     • the mount of force that can withstand from crushing.
   • Tensile strength
     • the amount of force being applied when pulled and is able to withstad his force/ pressure.
   • Elasticity
     • the elassticityv of a material is where it is able to stretch thewn able to return to its origianal length or shape.
   • Durability (1)
   • Toughness (1)
   • Hardness (1)

7. 7.2.7 Social footprint

   • Trend forcasting
   • Recycling and Disposal
   • Logging impact

8. 7.2.8 Ecological footprint

   • Sustainability
     • cstainability of timber is the idea that there are always trees available to be used. hardwoods trees take longer to grow, so are rarely re-planted once cut down. softwoods trees grow more quickly and are often planted in large areas of forestry. some forests now are sustainably managed, which means that trees are being replanted as soon as others arwe chopped down, so that there is always an area of the forests that is mature enough to be cut down. The forest stewardship council lets timbers produced use its logo on their timbers if that timbers come form forests that are shown to be sustainably managed. Schemes like this help consumersmake informed choices.
   • Deforestation
     • deforestation is a global problem, with the trees being cut down faster than they are being replanted. most of Europe was deforested hundreds of years ago and deforestation is now a major problem for areas of the developing world, such as south America and west Africa. deforestation can cause a lot of accompanying environmental issues such as soil erosion. for example, in Nepal deforestation has caused problems with landslides. worldwide about 46,000 - 58,000 square miles of forest is lost every year. this is an area size of England every year, or equivalent to 48 football pitches every minute. because trees absorb carbon dioxide form the air, scientists think having fewer trees will make the greenhouseeffect worse, which will warm the earth and affect the climate and sea levels for the whole world.d
   • Habitat impacts
     • forest destroyed. animals and humans loose their homes. can lead to extinction.
   • Processing
     • a process of converting logs into usable timber. kiln - drying ( heated and dry it out),  and burning off of unwanted wood.
   • Transportation
     • burning fuel by lorries and boats, increase carbon footprint.
   • Wastage
     • left to rot or not burnt if the land is being used for farming. larger branches will be cut down and uzsed to make MDF( manufactured density fibreboard), can cause skin irritation, health problems, nose and ear irritation.
   • Pollution
     • absorb carbon dioxide release oxygen. when burnt gives off carbon dioxide, which increases the greenhouse effect. other comes from the transportation atround the world.

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