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1. Timber is at great demand because it is accessible, ductile, processable, can be combined and has a nice look. Wood has a specific pattern, depending on the species. This is the most visible
in longitudinal sections, when the inner structure can be deduced.
2. Another trait of the timber is the existence of knots, circular or oval. Their shape depends on the angle of the log cut. Knots represent the inner part of the branches, located inside the trunk. The living branch are tightly fixed to the trunk, but the dead branch attachment to the trunk is loosened, and in the case of dry wood the knots can fall away from the log.
3. Woody material is of two types: hardwood (like beech, maple) and softwood (like fir, spruce). Exotic hardwoods are ebony, mahogany, teak or Brazilian greenwood. Hardwood is employed especially in furniture industry, but they grow slowly, that's why many wood reserves and forests have been depleted. In 1945, Taiwan's surface was covered in a proportion of 45 % by exotic forests. In 1989, the Taiwanese forests represented just 18% of the island's surface. Any wood exploitation is currently punished in Taiwan, while industrialized countries insist on stopping the import of hardwoods.
4. Most trees are cut down using high power chainsaws. The logs are cleaned of branches and transported to storing places using cranes or bulldozers. Land transport is made with trucks, while in India and Myanmar a more ecological method is used: elephants.
Transport can also be done via water. Logs are tied and, in remote areas lacking water trafficking, they are just let to be transported by rivers to the destination.
In most countries producing hardwood, processing industries are not developed, and hardwood is usually exported as logs to developed countries.
5. In timber plants, the bark is removed. The wood is cut using mechanic saws adjusted to the desired size. At this point, the wood still contains some humidity and its natural sap, so it must be dried first. The natural method of drying can take up to one year, that's why, in most cases, rapid driers are employed. The wood losing its humidity contracts and, in many cases, contorts. That's why the use of non-dry wood is not indicated. After getting dry, the wood stabilizes to some degree, as long as it is not put in contact with water.
Timber can be used for constructions, but the surface of the exposed wood must be further treated. Boards and slats are polished and painted or varnished. Usually, the best wood material is cut in thin sheaths, like veneer, and applied on wood of lower quality, to confer it a better look.
Stratified plates are made of thin wood plates glued, in such a manner that the direction of the neighboring fibers is orthogonal. This plate is more resistant than boards having the same size, it bends harder and it does not crack, contract or contort.
There are no wastes in the case of timber industry. By pinning low quality slats between higher quality plates, furniture plates are obtained. Ground wood is further minced, mixed with glue, and pressed to form agglomerated wood. The wastes can also be used in paper industry.
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