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Encyclopedia of Global Resources part 146 provides a wide variety of perspectives on both traditional and more recent views of Earth's resources. It serves as a bridge connecting the domains of resource exploitation, environmentalism, geology, and biology, and it explains their interrelationships in terms that students and other nonspecialists can understand. The articles in this set are extremely diverse, with articles covering soil, fisheries, forests, aluminum, the Industrial Revolution, the U.S. Department of the Interior, the hydrologic cycle, glass, and placer mineral deposits. . | 1356 Wood and timber Global Resources A pile of timber ready for processing. Vadimb Dreamstime.com applications. They are relatively strong and can be used in structural elements such as joists beams and columns. By comparison the stronger hardwood species such as oak are relatively heavy hard to handle and hard to nail. As far as construction is concerned their utility is limited they are generally used only in flooring cabinetr y and furniture. Supply and Disposal Wood is a renewable resource. It does not exist in finite quantities rather it is constantly produced in growing trees. If forests are carefully managed timber can be har vested on a sustained-yield basis year after year. Wood is also a reusable resource. The recycling of timber from old buildings is well documented. The ease with which wood can be cut Woody material is produced in many plants but its most useful manifestation is in the limbs and trunks of trees. There is a great diversity of tree species and most climatic zones have at least one that has adapted to the prevailing conditions within that area. Thus wood is generally available in most inhabited regions of the world. Wood has played a dominant role as a construction and engineering material in human society yet humankind has lived with this material for so long that its significance is easily overlooked. Hardwoods and Softwoods Trees are broadly classified into hardwoods and softwoods. These terms can be misleading since they are not connected to the actual hardness of the wood. Hardwoods are broad-leaved deciduous trees. Softwoods on the other hand have narrow needlelike leaves and are usually evergreen. Oak birch and basswood are common hardwood species whereas long-leaf pine spruce and cypress are softwoods. Some hardwoods oak are actually hard. Many others basswood are actually softer than the average softwood. In fact balsa is classified as a hardwood even though it is one of the softest woods in the world. By far the majority of .
