Land- To place logs into a landing during yarding or skidding operations.
Landing- A place where logs are collected prior to further transportation. See "Spot landing" and "Continuous strip landing"
Landing man- Worker who bucks, limbs, and trims log ends, unhooks chokers and assists in hooking up trailers to logging trucks. Also see "Chaser".
Lang lay- A type of wire rope more suitable for running through multiple sheaves. The wires making up the strands run the same direction as the strands themselves, giving greater flexibility. Compare to Regular Lay.
Lateral yarding- Any movement of logs toward the centerline of a yarding road.
Lateral yarding distance- The maximum distance perpendicular to each side of a skyline road within which logs can be attached for yarding.
Lay- a) The position of a felled tree on the ground. b) the
direction that strands of a wire rope are spirally wound around the
core.
Layout- a) a logging plan including units and roads. b) The
position of the running lines in a cable yarding system.
Lead- a) The direction of the operating or main line(s). b) A block or series of of blocks or rollers attached to a stationary object to guide the cable by which logs are dragged. c) The established direction in which all the trees on a given strip or setting are to be felled.
Lead, square- A yarding layout where the main line make a 90° angle with the axis of the yarder frame. Usually associated with spar trees where the yarder sled or frame is separate from the spar. Term is not useful with modern portable,standing spar towers.
Lead, straight- A yarding layout where the mainline is inline with the axis of the yarder and spar frame. Usually associated with spar trees where the yarder sled or frame is separate from the spar. Term is not useful with modern portable,standing spar towers.
Lead, V- A yarding layout where the angle between the mainline and the axis of the yarder and spar frame is less than 90°. AKA "diamond lead".Usually associated with spar trees where the yarder sled or frame is separate from the spar. Term is not useful with modern portable,standing spar towers.
Lean- The direction in which a tree or trees are leaning.
Leave strip- A strip of uncut timber left between cutting units. See "Buffer strip".
Leave tree- A tree left standing after timber has been felled in a cutting unit. Common reasons for leave trees are for seed sources, wildlife purposes, among others.
Length of ground- Used to describe whether the ground in a unit is badly cut up and rough or smooth and uniform.
Limb- a) n. Branch of a tree. b) v. To cut branches off a tree or log.
Line change- see "Change roads".
Line pulling- Felling trees against the lean by securing a line and pulling it over with a cat or line winch. This procedure is commonly required in stream protection areas. A form of "Directional felling".
Line swivel- A swivel in the butt rigging or line.
Live skyline- A standing skyline that can be raised and lowered to facilitate yarding. AKA "slack skyline".
Load- a) v. To pick up logs and to place them on a vehicle for transportation. b) n. The object(s) being hauled.
Loaded deflection- Deflection when the skyline is supporting a load of logs.
Loader- any of a variety of machines, wheel or track mounted, designed primarily to lift and load a truck, train or other mode of transportation. For some great history and discussion, go to:
http://www.aone.com/~robert/drott.html
Load path- The arc traced by a turn oflogs along a skyline and genrally plotted graphically to determine ground clearance.
Log- a) n. Any cut section of a felled tree. b) v. To harvest timber.
Log brand- An ownership identification mark stamped into the end of a log.
Log Deck- See "Deck".
Log Dump- A central unloading area for loads of logs.
Log rule- Any of several formulae, diagram layouts, or tables for estimating the volume of lumber that can be sawed from logs of a specific length and diameter.
Log scale-The lumber contents of a log as determined by a log rule.
Log train- A log hauling truck designed to haul only short logs; logs usually less than 20 feet long. The normal log truck needs bunk and side logs of 32 or more feet long to bridge from the front to the rear bunks.
Logging truck-A special 18-wheeled truck designed to haul logs from the woods to the mill. Lots of information on logging trucks and other forestry-related trucks can be found at:
http://www.aone.com/~robert/truck10.html
Logger- A worker employed in the woods producing wood products or in the support of such production, such as road construction.
Logging- Any or all part of converting trees into logs and transporting them to an unloading area.
Long butt- A swelled or cull portion cut off of a butt log.
Long corner- a) The distance from the landing to the farthest point of the setting. b) A small patch of timber in a setting that is difficult to yard or is unreachable.
Long log- To produce logs over 20 feet long , commonly 32 to 40 feet long. AKA "long wood".
Lowboy- A heavy equipment moving truck capable of transporting logging and earthmoving equipment distances greater than which they would move themselves.
Machine rate- The cost per unit of time to own and operate a piece of equipment.
Mainline- The cable used to haul logs into the landing. Some cable yarder configurations, such as running skyline, may have more than one mainline.
Mainline block- The block on the spar or tower through which the mainline runs.
Marginal log- The smallest log, in volume, that it pays a logger to remove from the woods. Often thought of as the breakeven log.
MBF- Thousand board feet. Often the log rule being used is appended, such as "MBF, Scribner."
Mobile spar or tower- See "Portable spar or tower".
Mobile tailhold- A crawler tractor or hydraulic excavator fitted with a fair lead or short spar used to hang tailblocks which simplifies and speeds up road changes.
Multispan
skyline-A skyline having one or more intermediate
supports.
Non-clamping carriage- Skyline carriage which is held in place by counter-tension of the mainline(s) and the haulback line, rather other than clamping to the skyline line a clamped carriage.
Notch- A wedge-shaped piece cut out of a stump to prevent a guyline or block strap from slipping off.
Nubbin- A metal knob or collar attached to the end of a choker, allowing it to be secured to a choker hook.
Off-highway truck- A truck designed to handle loads exceeding legal highway size and weight restrictions.
Offside- The side opposite that on which the cutter must stand to fellor buck a tree.
Open-side carriage- A skyline carriage that opens on one side to enable it to pass intermediate support jacks.
Opening line- A line used to open a grapple.
Optimum road spacing- The distance between parallel timber access roads which minimizes total logging cost.
Ordinary lay- See "Regular Lay"
Outhaul- The portion of a cable yarding cycle where the butt rigging or carriage returns to the timber from the landing for another turn.
Overrun- The lumber tally overage (MBF) produced from a MBF of log scale. e.g. If you get 1200 BF of lumber from 1000 BF of logs, then you have 20% overrun. Overrun is a product of the log scale being used (assumptions inherent in the log scale construction) and log diameter and length.
Paper plan- An initial timber harvest plan using available maps, aerial photos, and timber inventory data. It serves as the basis for field verification and adjustment to the final logging plan.
PC Logger- A Wintel desktop computer program which performs payload analysis for cable logging systems. Available from Oregon State University, College of Forestry.
Peaker- The top log on a loaded logging truck.
Pecker pole- A small log.
Peeler- A high grade log from which veneer is produced for plywood.
Peewee- A small merchanantable log.
Perpendicular felling- Timber felled at right angles to ground contour lines.
Pioneer- To do initial work over rough or unclear areas or to make a pioneer road.
Pioneer road- A primitive tractor-trail type of access for moving equipment, workers, and material.
Portable spar- A collapsible metal tower used in cable logging. AKA "mobile spar or tower".
Preload- To load logs or other wood products on to a trailer for subsequent transportation.
Prime mover- A tractor or other vehicle used to pull or power machines.
Profile- A graphic representation of the rise and fall of a section of ground surface as seen in a vertical section view. Most commonly used in road design and cable payload analysis.
Pulley- See "sheave"
Pulpwood- Small timber bucked to length (can be longwood or shortwood lengths) for use as a fiber source in a pulpmill.
Quarter- To fell trees across the hill at an angle rather than straight up or down the hill.
Radio whistles- See "Talkie Tooter".
Radio controlled carriage- A carriage that is operated by remote control with radio signals from the ground.
Raising lines- The cables used to up-end a protable spar.
Reach- a) A metal member connecting a logging trailer to the truck tractor. b) The distance spanned by a skyline.
Reconnaisance- The initial field examination of alogging plan to determine its feasibility. AKA "recon".
Recovery- That volume of timber which is recovered or saved after the felling and bucking operations are complete.
Reeve- To thread a line through a blockor other opening.
Regenerative brake- A device used on an interlock yarder which induces a retarding force on an outgoing line drum and transfers a portion of the power absorbed to an incomingline drum.
*Regular lay- The most common type of wire rope used in logging. The wires making up the strands are laid in the opposite direction than the strands themselves.
Reload- To transfer logs from one mode of transportation to another or between vehicles.
Relog- To salvage small timber, culls, or other residual wood products following the main logging operation.
Reprod- Short for reproduction or young trees.
Residual value- The actual or assumed value of a machine after it has been fully depreciated. AKA "salvage value".
Rigging- The cables, blocks, and other equipment used in yarding and loading logs.
Rigging slinger- The headman on a rigging crew who is responsible for choker setters and chaser and who selects the logs to make up a turn.
Rig-up- To prepare a tailhold, spar, or tower for yarding by guying and anchoring it, attaching all rigging and stringing the lines.
Rig-up block- A small block through which the straw line is strung in the brush; usually wide throated so that splices and connectors for the straw line segments can pass through the block.
Rimpull- The torque that a machine can exert at the contact
of its drive wheels to the ground; that is the tractive effort that a
machine can exert to move itself.
Road- The path followed by a turn of logs yarded
by a cable system. AKA "yarding road","skyline road", or "skyline
corridor".
Road change- See "line change".
Rolling resistance- The retarding force exerted by the ground against a vehicle's wheels.
ROPS- Roll Over Protection Structure. A sturdy structure built into or fitted around the operator cab on certain equipment which protect operators if the machines overturn.
Rub tree- A tree used as a fender or pivot for a moving line to protect the remaining stand during yarding. Usually will be so badly damaged after use that it must be cut down .
Running guy- See "sail guy".
Running line- A moving cable.
Running skyline- A yarding system with three suspended moving lines, generally referred to as the main, haulback, and slack pulling, that when properly tensioned will provide lift and travel to the carriage.