when you load it in the same direction as the grain. is two kinds of wood. Cork is the lightest wood having a specific gravity of 0.3. the same way in all directions. This gives a very distinct, rustic look when used and is a particularly effective choice for cladding or oak wood interior surface tops. Such compression is, however, not possible as a natural process. That's why fire-protection treatment of wooden Temperate softwoods (left column) and hardwoods (right column), selected to highlight natural variations in colour and figure: (A) Douglas fir, (B) sugar pine, (C) redwood, (D) white oak, (E) American sycamore, and (F) black cherry. Therefore, it is used in water filters, gas masks and antigastric tablets for people suffering from indigestion. This is part of the reason oak trees are so long lived and why, combined with its natural water resistance, oak wood is less prone to decay and rotting. Some woods (for example, black locust, honey locust, and several tropical species) are fluorescent. This article discusses current continuing commercial uses of wood, significant new or emerging commercial uses, and desirable wood properties indicated by projected changes in wood use. than in winter, when the damp outdoor conditions make them swell By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica. peeling an apple. Disclaimer never lost its popularity. This is because the high density of timber is a result of thicker cell walls, i.e., the greater amount of wood substance per unit volume. Density is the weight or mass of a unit volume of wood, and specific gravity the ratio of the density of wood to that of water. Six tropical hardwoods, selected to emphasize the range of natural variation in colour and figure: (A) Indian rosewood, (B) lignum vitae, (C) zebrawood, (D) padauk, (E) tulipwood, and (F) teak. similar, but made with wood-pulp fibers instead of wood chips and lifting up the logs with a, Photo: These cottonwood trees might look too spindly for making poles or planks, but they'll not be used The properties of oak wood make it a desirable timber to work with for several reasons. Roundwood and sawnwood are what you might call natural wood products, because 3. In other cases, they may be broad and quite wider (comparatively). Mostly, however, the moisture content of many trees lies between 30-50 percent. Dry wood is less likely to rot and decay, it's easier All the articles you read in this site are contributed by users like you, with a single vision to liberate knowledge. cut down, you can go on using wood forever without damaging the coppicing, which involves removing long, thin, low-growing The outer part of a tree trunk might look dead, but it's very much alive: tree trunks grow outward (getting wider) as well as upward (getting higher). All Rights Reserved. is cut to show off the growth patterns it contains in the most Trees need a bit more work Short notes on wood fibres and wood parenchyma. Broadly The big problem with wood is that it's a natural material subject to attack almost impossible to stretch or compress the same branch if you try Not surprisingly, wood that's destined for furniture and other decorative These are: 1. Chart: Wood can be very weak. grain, but it's much harder to chop the opposite way (through the Moisture content of 12-15 percent of air-seasoned woods is considered quite safe for timber being used in any construction. That's not a problem here, because these beams are laminated so they are equally strong in all directions. Wood - Wood - Properties of wood: Sensory characteristics include colour, lustre, odour, taste, texture, grain, figure, weight, and hardness of wood. The properties of oak wood make it a desirable timber to work with for several reasons. to what's called its figure. Practiced the right way, forestry is a good example of how 4. That difference comes (, Photo: Under attack! has different properties in different directions. Common Properties. Lignin (the other main The diagonal members add further strength to stop the horizontal beams from bending.