Spar tree at a logging camp in the United States, 1924
A spar tree is the tree used as the highest anchor point in a high lead cable logging setup. The spar tree is selected based on height, location and especially strength and lack of rot in order to withstand the weight and pressure required. Once a spar tree is selected, a climber would remove the tree's limbs and top the tree (a logging term for cutting off the top of the tree). Block and tackle is then affixed to the tree and cabling is run.
A "high climber" is the member of the logging crew who scales the tree, limbs it, and tops it.
Selecting a tree as a spar is a particularly important task, so the strength and importance of the spar came to hold symbolic meaning for early loggers of the West.
The use of spar trees in logging is now rare, having been replaced since the 1970s by portable towers, called yarders, which can be erected on logging sites and moved as needed.
A space elevator, also referred to as a space bridge, star ladder, and orbital lift, is a proposed type of planet-to-space transportation system, often depicted in science fiction. The main component would be a cable anchored to the surface and extending into space. An Earth-based space elevator cannot be constructed with a tall tower supported from below due to the immense weight—instead, it would consist of a cable with one end attached to the surface near the equator and the other end attached to a counterweight in space beyond geostationary orbit. The competing forces of gravity, which is stronger at the lower end, and the upward centrifugal force, which is stronger at the upper end, would result in the cable being held up, under tension, and stationary over a single position on Earth. With the tether deployed, climbers (crawlers) could repeatedly climb up and down the tether by mechanical means, releasing their cargo to and from orbit. The design would permit vehicles to travel directly between a planetary surface, such as the Earth's, and orbit, without the use of large rockets.
Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidding, on-site processing, and loading of trees or logs onto trucks or skeleton cars. In forestry, the term logging is sometimes used narrowly to describe the logistics of moving wood from the stump to somewhere outside the forest, usually a sawmill or a lumber yard. In common usage, however, the term may cover a range of forestry or silviculture activities.
Lumberjacks are mostly North American workers in the logging industry who perform the initial harvesting and transport of trees for ultimate processing into forest products. The term usually refers to loggers in the era when trees were felled using hand tools and dragged by oxen to rivers.
The timber hitch is a knot used to attach a single length of rope to a cylindrical object. Secure while tension is maintained, it is easily untied even after heavy loading.
Ochroma pyramidale, commonly known as the balsa tree, is a large, fast-growing tree native to the Americas. It is the sole member of the genus Ochroma. The tree is famous for its wide usage in woodworking, due to its softness and its high strength compared to its low density. The name balsa is the Spanish word for "raft."
Tree climbing is a recreational or functional activity consisting of ascending and moving around in the crowns of trees.
A lunar space elevator or lunar spacelift is a proposed transportation system for moving a mechanical climbing vehicle up and down a ribbon-shaped tethered cable that is set between the surface of the Moon "at the bottom" and a docking port suspended tens of thousands of kilometers above in space at the top.
A guy-wire, guy-line, guy-rope, down guy, or stay, also called simply a guy, is a tensioned cable designed to add stability to a free-standing structure. They are used commonly for ship masts, radio masts, wind turbines, utility poles, and tents. A thin vertical mast supported by guy wires is called a guyed mast. Structures that support antennas are frequently of a lattice construction and are called "towers". One end of the guy is attached to the structure, and the other is anchored to the ground at some distance from the mast or tower base. The tension in the diagonal guy-wire, combined with the compression and buckling strength of the structure, allows the structure to withstand lateral loads such as wind or the weight of cantilevered structures. They are installed radially, usually at equal angles about the structure, in trios and quads. As the tower leans a bit due to the wind force, the increased guy tension is resolved into a compression force in the tower or mast and a lateral force that resists the wind load. For example, antenna masts are often held up by three guy-wires at 120° angles. Structures with predictable lateral loads, such as electrical utility poles, may require only a single guy-wire to offset the lateral pull of the electrical wires, at a spot where the wires change direction.
A yarder is piece of logging equipment that uses a system of cables to pull or fly logs from the stump to a collection point. It generally consists of an engine, drums, and spar, but has a range of configurations and variations, such as the swing yarder.
A portaledge is a deployable hanging tent system designed for rock climbers who spend multiple days and nights on a big wall climb. An assembled portaledge is a fabric-covered platform surrounded by a metal frame that hangs from a single point and has adjustable suspension straps. A separate cover, called a stormfly, covers the entire system in the event of bad weather.
Cable logging, also referred to as skyline logging, is a logging method primarily used on the West Coast of North America with yarder, loaders, and grapple yarders, but also in Europe.
High lead logging is a method of cable logging using a spar, yarder and loader. It was developed by Oscar Wirkkala. It is accomplished with two lines (cables) and two winches. The mainline or yarding line extends out from one winch, while a second usually lighter line called the haulback line extends out from the other winch to a 'tail block' or pulley at the tail (back) end of the logging site, and passes through the tail block and connects to the main line. Butt rigging is installed where the two lines join and the logs are hooked to the butt rigging with chokers. The procedure is to wind up the main line and the logs are pulled in, wind up the haulback and the butt rigging is pulled out for more logs or another 'turn'.
The Washington Winch sits in the forests of eastern Victoria near Swifts Creek and is also known as the Washington Iron Works Skidder.
The Philippine flying lemur or Philippine colugo, known locally as kagwang, is one of two species of colugo or "flying lemurs". It is monotypic of its genus. Although it is called "flying lemur", the Philippine flying lemur is neither a lemur nor does it fly. Instead, it glides as it leaps among trees.
Felling is the process of cutting down trees, an element of the task of logging. The person cutting the trees is a feller. A feller buncher is a machine capable of felling a single large tree or grouping and felling several small ones simultaneously.
Gilbert Joseph "Bus" Griffiths was a cartoonist, lumberjack, and fisherman. He was best known for his graphic novel Now You're Logging, published 1978 by Harbour Publishing. Now You're Logging presented, in cartoon form, a complete look at the techniques, tools, and personalities of logging on the West Coast in the 1930s.
The Lumberjack World Championships are held annually in Hayward, Wisconsin. The event began in 1960 and is held at the Lumberjack Bowl. There are 21 events for both men and women to compete for over $50,000 in prize money. Contestants come from the United States, Canada, Australia, and New Zealand. The events include sawing, chopping, logrolling, and climbing to test the strength and agility of over 100 competitors.
Heli-logging, or helicopter logging, is a method of logging that uses helicopters to remove cut trees from forests by lifting them on cables attached to a helicopter. Helicopter logging is often used in inaccessible areas of forests. Because the use of helicopters reduces the level of infrastructure required to log in a specific location, the method also helps to reduce the environmental impact of logging. It also can increase the productivity in these remote areas.
Tree volume is one of many parameters that are measured to document the size of individual trees. Tree volume measurements serve a variety of purposes, some economic, some scientific, and some for sporting competitions. Measurements may include just the volume of the trunk, or the volume of the trunk and the branches depending on the detail needed and the sophistication of the measurement methodology.
A climbing gym is a gym dedicated to indoor climbing. Climbing gyms have climbing walls that can be used for leading, top roping, and bouldering. They sometimes offer training equipment to improve technique, strength, and endurance.
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