Logging 2 Essay, Research Paper
Logging in the Northwestern United States has been a major part of its economy almost since it s settlement. In the movie they noted that most of the mainland had been cleared for housing developments and high-rises. This interested me, in the movie they used the cedars to protect them from the prejudiced society, the trees became a place they could live without fear of being torn apart by an unjust world. On the mainland they had removed all the trees, and so they had removed they re innocence. When the two young lovers left the shelter of the trees they also left behind they re innocence. I think the logging industry in America helped removed the innocence of the country, but at the same time instilled a more realistic perspective in the people of this country. How was this accomplished, was the first question that occurred to me. How did they remove the majority of the forests in America? What techniques did they use both now and then to go about cutting down and removing the trees? What did they do with all of the wood?
People started cutting down the tree in the America s nearly as soon as they got off the boat. They used the lumber to construct they re first houses, and other essential buildings. The forestry industry got its official start in 1633 with the construction of the first sawmill in the colonies. Today approximately 12,000 sawmills are operating in the United States (logging book). Soon though the colonies were shipping lumber back to England for they re buildings and ships (Encarta forestry industry). They cleared all the land up to the Appalachian Mountains with little resistance. After the American Revolution they began crossing these mountains and settling the plains for farming this demanded land free from trees. The farmers used a technique called cut and burn. This is when the lumber people go through and cut the best trees for their use and burn the rest in an effort to clear the land for some other use. In this fashion they worked they re way all the way to the northwestern United States. Here they found much bigger trees the Redwood, and Douglas firs, which grow to enormous proportions. All the way up to the twentieth century the logging companies cut trees without regard for the future. At this point most of the old growth had been cut for immediate use without any regard for any future need (Encarta, Logging history). In all the forestry industry in the United States cleared one half of its forests by 1900. Of the 583 million acres left 2/3 are owned by commercial logging companies. The other 1/3 is tied up in Federal and State parks and preserves, according to the article Forestry Industry in the Encarta encyclopedia.
The early loggers had a difficult job in cutting down the trees that were hundreds of times larger than they were. These men were charged with finding quick, efficient and safe ways of removing the trees. The early methods relied mainly on physical force of the loggers and their animals. To accomplish this the loggers would prepare the camp for the year before the September start of the logging season. They would cut paths and roads through the trees, and also set up they re essential buildings such as sleeping and eating quarters. Usually the early loggers usually used one of two animals horses or oxen, they would harness the animals and use them to move the heavy fallen lumber (logging book). The tree cutters would work in pairs they would use poorly sharpened saws and axes to chop or cut the trunk of the tree, allowing it to fall where it may. After this they removed the branches and other protrusions from the tree. Next another member of the logging team attached the tree, by way of harness, to their animal; finally using the paths they drove the animal to the nearest waterway. After placing the log in the water they then drove them downstream to the sawmill (lumber industry Encarta). Once the logs arrived they were manually cut using a wide arrange of saws and various cutting instruments and then shipped via boat or wagon to the desired locations.
Today however logging is a very different process, involving technologies, such as chain saws and computers. In the modern cutting of trees they use a wide range on tool. The type of tree cutters used today depends on the type of terrain. If the area is relatively flat a mechanical feller called a shear is used to clear the trees. The shear has two blades that work like a pair of scissors, cutting through the trunk of the tree and carefully laying it on its side. The shear works very quickly, it can take as little as 30 seconds to cut a tree 8 inches thick. A shear working on level terrain can cut 25 cords of wood per day. Two men working with a chain saw can only clear about 4 cords of wood in the same amount of time. The chain saw has an advantage over the shear on the large trees located in the Pacific Northwest. Here the cutting blades of the shear cannot fit around the enormous trunks of a Douglas fir or a Redwood tree. The chain saws can slowly but surly make it all the way through the enormous trunk of these giant trees. Now unlike the days before all the technological advances in the field when the cutters fell a tree they carefully plan where to lay the trees down without crushing people or damaging other trees in the process. Next the limbs and branches of the tree are bucked. This is a way of saying they remove the excess limbs, which make moving the trees extremely hard. When the land is flat a grapple skidder is used to haul the trees to the landing. On slightly slopped land a tractor is used to move the logs. When logging on a slope with a greater incline a cable yarder is sometimes used. This involves hooking a pulley to the top of a tall tree close to where you want to move the log. The rope is then attached to a drum, which reels in the cable. The other end is attached to the tree to be moved, the cable is then brought in and so is the desired tree. This method can move large logs up to 500 feet. Once the logs are moved to the landing they are stacked and loaded onto trucks or railroad cars to be moved to the sawmill (logging book).
At the sawmill the tree is first debarked, they use several different methods to accomplish this task quickly and effectively. One method uses highly pressurized water to strip the bark cleanly off the tree. Another method uses a blade to peel the bark back off the tree, and yet another uses a large metal drum in which the bark is literally beaten off the tree. The bark is used for many different products including paper, mulch, chipboard and fuel. Once the log is debarked a computer is used to measure and cut the log into boards. The saw used to cut a log in to boards is called the head saw, and a chipping head rig is used to cut the sides of the log. Next a trimmer is used to cut the end of the boards, and finally an edger smoothes the edges. These newly cut logs are referred to as green wood; this kind of board is not used in building because as it dries it shrinks. The boards need to be seasoned; this is the process of drying the boards before selling them so they will have already been dried and shrunk. A kiln is sometimes used to heat the boards to season them more rapidly. Other times the sawmill decides to use the logs for something other than lumber, the logs might be turned into veneer. Veneer is a very thin sheet of wood; it has been used as an instant decoration for hundreds of years. Veneers can also be glued together to form plywood, which is a cheap building material used as the backbone of walls in countless houses around the world. To create plywood the sheets of veneer to be used are dried, after they are free of excess water they place glue between the sheets laying each sheet opposite the grain of the previous. This is done to make the plywood unusually strong; once the glue is in place the plywood is set in a press for a length of time (logging book).
If the trees are not made into lumber it is a fairly safe assumption that it might be made into some form of paper. Once the wood arrives at the paper mill it is placed in vats of certain chemicals one of the most commonly used is magnesium sulfate. This solution is used to digests or breaks up the particles of wood into a liquid form referred to as pulp. The pulp can now be dyed if colored paper is desired, or bleached for a whiter white paper. Most paper today is made on Fourdrinier machines, which were developed in 1803 by the brothers Henry and Sealy Fourdrinier. The heart of this machine is a circular belt of wire mesh that moves horizontally. The Watery pulp is introduced on the level belt, which passes over the rolls. A wooden box beneath the belt catches the water that drains during this stage. This water is later remixed with the pulp to salvage the fiber it contains. Rubber deckle straps at the sides of the belt prevent spreading of the sheet of wet pulp on the wire belt. Air suction pumps beneath the belt speed up the drying of the paper, and moving the belt side to side to side-to-side quickens the felting of the fibers. As the paper travels along the belt it passes under a turning cylinder called a dandy roll. The cylinder is covered with wire mesh to leave a wove or laid surface on the paper. In addition, the surface carries words or patterns worked in wire; these are impressed on the paper and appear as watermarks that identify the grade of paper and the maker. In handmade papers, the watermark patterns are fixed to the surface of the mold. After this the paper is fully formed, it is then carried through a series of heated rolls, which complete the drying. The next step is calendaring, pressing between smooth chilled rolls to produce the smooth finish known as machine finish. The paper is allowed more time to dry completely and is cut in to the desired sizes via machine.
The preceding account of the logging industry has been an inquisition inspired in part by the movie and/or book Snow Falling On Cedars by David Guterson. I attempted to give an unbiased account of the logging industry, its history and present techniques and products produced by said industry. I hope it was enjoyable as well as informative, providing you with a new level of knowledge of a well know subject
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