Additional literature and resources. 3. Clive Oxenden, Christina Latham-Koenig New English File Advanced

1 Read the text “Hardwood and Softwood”

Long time ago, carpenters determined quality of wood according to their utility purposes. Wood quality was identified by wood’s appearance through using traditional methods and carpenters’ experiences. Those could be considered as first methods of wood classification and used to be applied in church constructions (in Middle Ages), ship building (from 16th to 19th century), railway slipper and construction of bridges (end of 19th century).

As a product of nature, timber embraces specific features in strength, appearance and defects. Therefore, in order to use this kind of material in the most proper way, people should be fully aware of its characteristics and their utility. It can be said that wood classification is extremely important for differentiation of specifications in regards of utilization. Moreover, timber classification is to ensure that buyers and sellers use the same commercial languages to unify and codify empirical practises and general costumes. The specific objectives of timber classification are the follows:

· to sell the timber at highest value possible depending on species, diameter classes and different quality classes (wood quality can be classified according to defects such as knots, checks, bend, holes, etc.);

· to develop precise rules to be able to refer in case of disputes.

It is shown that grading and classification has to pay off at the end for the seller of the logs. The given example from Germany (March 2008) of the results of a closed tender of high quality oak timber (about 8.600 m³) supplies evidence of the success of classification according to 6 diameter and 5 quality classes.

	Hardwood and Softwood You may have heard people talking about two different kinds of wood - hardwood and softwood. Surprisingly, these names have almost nothing to do with how hard or soft their woods are! In fact some softwoods are harder than hardwoods! The names hardwood and softwood have to do with the trees that the wood comes from. Hardwood comes from broadleaved trees. These are the sort of typical native British trees like oak, ash and beech. Most of these trees are deciduous; they lose their leaves in the winter. There are about a hundred times as many hardwood species as softwoods. Hardwoods are generally far more resistant to decay than softwoods when used for exterior work. In the past, tropical hardwoods were easily available but the supply is now restricted because of the concern about the conservation of tropical forests.
	Softwood comes mainly from evergreen, coniferous trees which keep their foliage all the year. These are trees like pine and fir trees that are typical of cooler parts of the world. In general softwood is easy to work and has a huge range of uses. It is the prime material for structural building, but is also found in furniture and other products such as doors andwindows. Softwood is also harvested for use in the production of paper.
One of the most commonly used materials all around us is wood. There are many different kinds of woods with wide ranging mechanical, physical, and thermal properties, which make them suitable for different applications. From building houses to making kitchenware, wood is an ideal and easy to use material. In general, wood is broadly available at reasonable prices and is easily formable, making it desirable for construction work. Of course, depending on the application, different properties of wood are desirable. For example, for building a house with wood, high strength is desired, whereas for making a cutting board, you probably want something that has a harder surface so it doesn’t get dented easily. There are a large database of all kinds of wood and their various properties.

Let’s generate a quick report of properties pine wood

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