A good quality timber should be hard enough to resist deterioration.
It should have sufficient strength to resist heavy structural loads.
It should have enough toughness to resist shocks due to vibrations. It should not break in bending and should resist splitting. Timbers having narrow annual rings, are generally the strongest.
It should have the property of elasticity so as to regain its original shape after removal of loads. This is a very important property to be considered if the timber is used in making sport goods.
It should be able to resist attacks of fungi and worms and also atmospheric effects for a longer period of time.
Timber should be prepared from the heart of a sound tree and be free from sap, dead knots, shakes and other similar defects.
7. Fibres and Structure
It should have straight and closed fibres and compact medullary rays. It should give a clear ringing sound when struck. Dull heavy sound is an indication of internal decay. Its annual rings should be uniform in shape and colour.
8. Appearance and Colour
Freshly cut surface should give sweet smell and present shining surface. It should have dark colour, as light colored timbers are generally weak in strength.
9. Shape and Weight
It should retain its shape during the process of seasoning. Heavy timbers are always stronger than light weight timbers.
It should be well seasoned and easily workable. Teeth of saw should not get clogged during the process of sawing. It should provide smoothened surface easily.