Logging Terminology, A to C:

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B

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Active falling area- The area within two tree-length radius of where a faller or a mechanized falling machine is operating.

Adverse (grade)-Ascending grade in the direction of travel

Aerial logging- A logging system which fully suspends the logs such as done by helicopters or balloons. Not to be confused with cable systems which use cables and supports.

Anchor- A stump or wooden, concrete, or metal device secured in the earth to
hold a line securely. Also see "deadman".

Anchor line- A line to used to tie down a yarder to prevent tipping. Also see "guyline".

Arch- A framework through which a winchline from a skidder passes over and is used to suspend the leading ends of logs being dragged(skidded).

Arched skidding- Skidding logs with an arch to raise the front of the logs off the ground; as opposed to "ground skidding".

Average yarding distance- Often abbreviated as AYD, the total yarding distance for all turns for a particular logging setting or unit divided by the total number of turns. Usually expressed as slope distance, unless otherwise stated.

Backcut- The final cut in felling a tree by hand, made on the side opposite the intended direction of fall, after the undercut.

Bar or blade- That part of the chainsaw upon which the cutting chain moves.

Barberchair- A vertical split in a tree, generally caused by an insufficient undercut or by neglecting to cut the sapwood on both sides of a heavy leaning tree before felling. Results in a stump which looks like a high-backed chair. Very dangerous to the faller.

Back guy- The guy line(s) behind the spar, opposite the lead of the main line or skyline in a cable logging setup. Usually applies to standing towers, rather than to swing towers.

Back spar- See "Tail spar".

Beaver-tailing- Burying the whole bar of a chainsaw into the log or tree while cutting

Bed- The intended position in which a tree will be felled. In old-growth redwood timber (Sequoia sempervirens), a bed is created by a bulldozer from piled up earth and slash so as to cushion the fall of these brittle giants.

Bell- A type of choker hook that slides on the choker wire between the two knobs.

Belly- A sag in any line.

Bight- a) Any section of a line between the ends. b) A band or sag in a line under tension. c) A work area made hazardous by a line or equipment under tension.

Bind or bound- Compression created in a cut in a tree or log due to uneven terrain or contact pressure from other trees or logs. This will result in the chainsaw being caught in the log or tree.

Binder- A wire rope placed across a load on a logging truck to secure the load. AKA "wrapper".

Blade- (a) n. The part of a bulldozer or grader which digs and pushes dirt but does not lift it. (b) v. To scrape or level a mound of dirt or area of ground with a blade. e.g. "It was necessary to blade the landing to smooth it for use."

Blind lead- The situation on a convex slope where the line of sight from the tail block to the yarder tower's mainline or skyline fairlead block (bull block) is obstructed. May result in hangups to the logs being yarded if ground leading rather than full suspension is being used or available.

Block- A wooden or metal case enclosing one or more pulleys used to lead a line in a specific direction, and provide with a hook, eye, or strap by which the unit may be attached to an object, such as a spar tree or anchor.

Board foot- The standard unit of measure for standing timber, logs and lumber in the United States. A board foot is represented by a board one foot wide, one foot long and one inch thick. A unit in board feet is usually expressed in 1,000 board feet or MBF. For example, 28,500 board feet is expressed as 28.5 MBF. The number of MBF in a log or stand of timber is a function of the "log rule" used in the local area. Different log rules will yield different estimates of MBF based on the log rule's assumptions.

Bole- The trunk of a tree, especially the merchantable or useful portion.

Boom- A raft of logs or a string of logs chained together, end to end, used to hold floating logs. A means of log storage or transportation.

Breaking Strength- The greatest load that a wire rope or other material can withstand before breaking. Also known as the "ultimate strength'. Compare to "working strength".

Break out- To get a log out of a hang-up or its initial lay on the ground.

Brow-log- A log placed parallel to the roadway at a landing or dump. Sometimes also called a bumper-log.

Brush monkey- Usually the newest member of the cable yarding crew, usually assigned the worst or least desirable tasks, an entry-level logger.

Brush-out or swamp-out- To clean out brush or other material around the base of trees to be felled or logs to be bucked so as to provide safe footing, prevent saw kickbacks, and to provide an escape path for the faller.

Buck- To saw felled trees into log lengths. Note: In some two person felling operations, one member may fall the tree and the other may limb and buck it. The second person is often called a "bucker". Usually the two members interchange the duties throughout the work day.

Buckskin- A log or tree with the bark fallen off.

Buffer strip- A leave strip of timber along a watercourse or lake for environmental reasons, such as shade, future large woody debris recruitment, sediment filtration, and other benefits. Usually excludes equipment entry, but often permits the logging of some trees. May also be called a Watercourse And Lake Protection Zone (WLPZ, in CA), Riparian Management Zone (in OR), Stream Protection Zone, or other terms depending on the region and organization.

Bullbuck- The foreman of a cutting crew.

Bull block- The mainline lead block in high lead logging.

Bulldozer-See "Cat", AKA "dozer"

Bull hook- A hook for attaching chokers to a line. AKA "butthook" in highlead logging.

Bump knots- To cut knots off of a log. The worker on the landing who trims up logs and cuts off missed limbs and branch stubs is often called a "knot bumper".

Bunch- To assemble several logs together to form a load for subsequent skidding or yarding.

Bunk- a) A crossbeam on a truck on which the logs rest. b) To place the empty trailer of a logging truck on the tractor unit's bunk for the trip back to the landing

Bunk log- Any log resting on the bunk of a truck.

Busheler- A logger or contractor who works at piece rates. More commonly called a "Gypo" in the western U.S. Usually used to refer to independent loggers versus company hired loggers.

Butt log- The first and biggest log from a tree.

Butt hook- The heavy hook on the butt rigging to which the chokers are attached in high-lead cable logging.

Butt rigging- A system of swivels and clevises which connect the haulback and mainline together and to which butt hooks are fastened. An essential part of the high lead, cable logging system.

Cable- Actually more correctly termed a wire rope (see Wire rope).

Cable logging- A yarding system employing winches and cables from a fixed position (usually a yarder and tower of some sort).

Cableway- The location or pathway of a cable suspended between elevated supports so as to constitute a track along which log carriages can be pulled.

Carriage- A load-carrying device from which logs are suspended and which rides back and forth along the skyline on sheaves for yarding. Also called the "skyline carriage".

Cat face- Deformed tree trunk surface usually caused by fire, disease or rot.

Catenary curve- The shape assumed by a cable suspended freely between two points.

Cat- Often short for Caterpillar tractor, or any other brand of bulldozer-type tractor. May refer to a skidding tractor or a earthmoving bulldozer.

Cat road- A path created by tractors for skidding logs, or any crude roadway or path cut by a bulldozer. AKA "skid trail" or "skidroad".

Cat skinner- The person who operates a cat.

Caulks- Short spikes driven or screwed into the bottom of loggers' boots to give footing while walking on logs or wood. Calked boots are considered essential for woods personnel in many parts of North America, especially where cable yarding is done. Also spelled "calks" or "corks".

Chain and board- A graphical method of calculating skyline load path and deflection by pinning a length of light chain (e.g.: lamp pull chain) to a drawing board covered with grided cross-section paper on which cableway ground profiles have been drawn to scale. Methodology is described in the Publications and References.

Chance- A logging show or operation

Change roads-To move rigging and running lines to progressively yard logs from the next area in the felled and bucked timber. AKA "line change".

Chase- To unhook chokers from the logs at the landing. The person doing this is called a "chaser".

Chip- to mechanically reduce logs or whole trees to small pieces for fuel, pulp, or chipboard manufacture. The equipment is called a chipper. See "clean chips" and "dirty chips". May also be called "in-the-woods" chipping.

Choker- A short (usually less than 20 feet) noose of wire rope for hauling logs.

Choker setter- the person who puts a choker around a log and attaches it to the skidding or yarding equipment.

Chord- A straight line between skyline support points.

Chord slope- The slope, in percent or degrees, of the skyline chord.

Chute- The area at the landing where logs are landed on a high-lead or cable logging operation.

Clean chips- Wood chips for pulp manufacture without any bark included, requires a chipper with a debarker.

Clambunk- A specialized forwarder designed to skid tree-length logs.

Clamped carriage- A skyline carriage which clamps to the skyline when stopped and picking up logs. Clamped carriages produce more severe loading condition on the skyline than do unclamped carriages.

Clevis- See "shackle".

Climbing spurs- Irons with sharp side spurs, strapped to the legs at the ankle and below the knee. Used by riggers to climb trees for topping and rigging. Part of this geat is is a climbing rope and belt. AKA "spurs".

Closing line- A line used to close a grapple or tongs.

Cold deck- A stack of logs left for later transportation (in the woods), or a deck of logs at the mill for winter use.

Continuous strip landing- A section of roadway used as a landing in a cable logging operation where the yarder, loader, and logging truck are in a line along the road. The operation often moves down the road as logging progresses. The opposite would be a "spot landing".

Contour felling- Timber felled parallel to ground contour lines on the slope.

Cord- A unit of wood volume equal to 128 cubic foot of stacked wood. Commonly used for smaller timber utilized for firewood or pulping.

Corner block- A block off to the side which is used to guide the haulback line. AKA "haulback block".

Corridor- see "cableway".

Counterweight-Extra weight added to the rear of any mobile equipment to increase lifting capacity.

Counterweight clearance-The distance from the counterweight to any stationary object. Minimum clearance is usually set by various OSHA-type rules governing the jurisdiction logging is occuringin.

Crawler- Any track propelled machine in the woods.

Crossing the lead- Felling a tree at an angle across the established felling pattern.

Crummy-A vehicle used for crew transportation to and from the woods.

Cull- Any log or tree which is unmerchantable due to size, defect, or damage. May also be used to describe something which is generally worthless, e.g. " As a choker setter, he was a cull."

Cunit- A unit of wood volume measuring 100 cubic feet . More commonly used for estimating smaller timber to be utilized for pulping or firewood. However, in the 1990s, the U.S. Forest Service began to sell all timber based on the cubic foot volume rather than MBF.

Cut-to-length harvester (CTL)- A self-propelled tracked or wheeled harvesting machine, designed to fell, limb, and buck a tree into logs, usually 20 feet or less in length. Most commonly the harvesting head is mounted to an articulating arm. Not to be confused with a full-tree length harvester or feller-buncher. Most commonly CTL harvesters work with forwarders which transport the bunched log piles to the landing.

Cut, rigging - AKA "weakening cut". A tree lying in such a position that a normal bucking cut can not be made safely. In order to facilitate yarding or skidding, the faller will make partial bucking cuts from a safe position, perhaps two log lengths apart.

Cut slope ratio (CSR)- The slope of a cut bank on the road or landing. Usually expressed as a ratio of X:1, where X is the number of feet run per one foot of rise. Hence a CSR of 2:1 is flatter than one of 1:1. Often of importance when a swing yarder is setup on a road and the road is used as the landing.

Cutting Pattern- The visible pattern to which trees are felled during a cutting operation.

Cutting unit- An area of timber designated for harvest. Several cutting units may make a timber harvest plan or a timber sale.

Cycle- A complete set of operations or tasks that is repeated. Also see "turn".