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Industry Terms and Definitions

Below you can find a glossary of terms related to the lumber and timber industry to help you better understand SPTP’s products and services and how they can benefit your organization. 


A chemical used in wood preserving; it is usually applied under pressure so that it will penetrate the wood


Precision end trimmed; lumber trimmed square and smooth on both ends, to a uniform length with a manufacturing tolerance of 1/16 inch over or under length in a maximum of 20% of the pieces


Round timbers or poles that are driven into the ground to support a load, as a foundation for a structure, or as part of a dock or moorage


Any of the various softwoods of the genus Pinus

Pine beetles

Insects that bore into the bark of pine trees to lay eggs; the larvae of the beetle feeds off the cambium layer of the tree, eventually killing it


1. An accumulation of resign in the wood cells in a more–or–less irregular patch; classified for grading purposes as light, medium, heavy or massed 2. The angle or inclination of a roof, which varies according to the climate or materials used 3. The set, or projection of teeth, on alternate sides of a saw to provide clearance for its body


The small, soft core in the structural center of a log


A machine used to surface rough lumber or timber

Planing mill

An installation where lumber is surfaced; also refers to mills where lumber is remanufactured to a customer's specifications


A flat panel made up of a number of thin sheets, or veneers, of wood in which the grain direction of each ply, or layer, is at right angles to the one adjacent to it; the veneer sheets are united, under pressure, using a bonding agent


A long, usually round, piece of wood, often a small diameter log with the bark removed, used to carry utility wires or for other purposes; often treated with a preservative


A lumber item that is cut to a precise length at the time of manufacture so that it may be used in construction at the jobsite without further trimming


Lumber that has been drilled at the mill to accommodate bolts or other hardware


Any substance applied to wood that helps it resist decay, rotting or harmful insects

Pressure treating

A process of impregnating lumber or other wood products with various chemicals, such as preservatives fire retardants, by forcing the chemicals into the structure of the wood using high pressure


A grade of finished lumber, ranking below superior, the highest grade, and above E, the lowest grade of finished; finished graded prime must present a fine appearance and is designed for application where finishing requirements are less exacting


Wood used to produce pulp used in the manufacture of paper products; pulpwood is usually wood that is too small, of inferior quality, or the wrong species to be used in the manufacture of lumber or plywood