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​Properties of wood: there are two distinct properties of wood they are as follows:

Physical properties: generally describe to denote such inherent quality as the appearance, colour,

density etc.

1. Mechanical properties: generally indicates the ability of wood to resist various external

forces, static or dynamics that may add on it.

Hardness: Generally indicates the ability of wood to resist various types of external factors which

depends on nature of grain present or deposited of silica and other chemical substances. The hardness

of wood depends on the following factors:

1. Anatomical structure: the degree of unity of fibres determines the hardness of wood.

2. Specific gravity: generally, hardness increase with specific gravity i.e. slow growth/ grown

conifers. Timber is harder than fast grown of wood of the same species.

3. Moisture content: Dry-wood is harder than greenwood.

4. Present of resinous material: deposit of resinous material increases the hardness

5.

Soundness: the decay is always softened the wood by disintegrating tissues.

The following is the classification of wood according to hardness:

1. Extremely hard: Shorea robusta, Acacia catechu, Mesa firea, albergia latifolia, etc.

2.

Very hard: Terminalia species, Dalbergia sissoo, Morus alba, Syzygium cumini, etc.

3. Hard: Lagerstromea parsiflora, Lagestormea, floregenae, Tectona grandis, Adona cordifolia

4. Moderately soft: Mangifera indica, terminalia myriocarpa, etc.

5. Soft: cedrus deodora, Toona celiata Abies pindrow, etc.

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6. Very soft: Pinus keshya, Pinus roxburghii, Pinus wallichiana, etc.

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Durability: it is meant the property of wood to remain sound and unaffected by the attack of fungi

insect, pest and other wood destroying agent. Durability is of vital necessity such as for construction

of house building railway sleepers ship building industries etc. undurable wood required to be

artificially seasoned

Factors affecting the durability of wood:

1. Moisture content: the presence of sap reduce the durability of wood. Moisture content is an

important factor for fungus attack welled seasoned wood is less subject to fungus attack than

green wood

2.

Specific gravity and hardness: heavier and harder wood are more durable. Hardness

opposed the attack of insect and barriers, hence it increases durability.

3. Presence of resin and oil in wood: the content and discharge of wood-oil affected durability

considerably and presence of toxic substances such as wood oil, gum, resin, etc. keep away

fungi & insect- pest attack

4. Uses of wood: in dry location or submerged in water is liable to decay or rot. If a wood is

embedded in the ground and presence of organic matter in the soil or lying in the damp

ground encourage the decay.