How to Understand “Forest-ese”

Following is a brief glossary of the “forest language” spoken by the forest products industry, as well as by state and federal regulators.
There are more forest glossary terms available from Wood Links USA.

Annual Growth:

The yearly increase in wood volume, usually expressed in terms of board feet.

Annual rings:

Bands that show tree growth for one year, as viewed on the cross section of a stem, branch or root, or on a trunk core sample. Can be counted to determine a tree’s age. Variation in width of rings records how the tree responded to growing conditions in different years. (Click here to learn more about tree rings.)

Best Management Practices:

(Also known as “BMPs”)
Common-sense actions required, by law, to keep soil and other pollutants out of streams and lakes. BMPs are designed to protect water quality and to prevent new pollution. (Click here to go to a discussion of Best Management Practices.)

Board Foot:

A unit for measuring wood volumes equaling 144 cubic inches, commonly used to measure and express the amount of wood in a tree, sawlog or individual piece of lumber. For example, a piece of wood measuring 1-foot x 1-foot x 1-inch or a piece measuring 1-foot x 2-inches x 6-inches each contain 1 board foot of wood.

Buffer Strip:

A protective strip of land or timber adjacent to an area requiring attention or protection. For example, a protective strip of unharvested timber along a stream.

Burning Methods:

Controlled Burn: Any burning that a landowner starts intentionally and controls to accomplish a particular purpose, such as brush or slash reduction.
Prescribed Burn: Application of fire to land under conditions of weather, soil moisture and timer of day, that will accomplish specific silvicultural, wildlife, grazing or fire-hazard-reduction purposes.


The tree crowns in a stand.

Commercial Timberland:

Forestland that is producing or capable of producing at least 20 cubic feet of industrial wood per acre per year and is not withdrawn from timber utilization by statute or administrative regulation.


A stack of wood containing 128 cubic feet. The standard dimensions are 4 x 4 x 8 feet.


The branches and foliage of a tree.


A survey of forest land to estimate timber quantity.


A plant community dominated by trees and other woody plants.


An educated professional responsible for planning and producing healthy and sustainable forests.

Forest Industries:

A diverse group of manufacturers that harvest, process and use timber products in their final products. Activities include the harvesting of the timber resource; conversion of logs to primary timber products such as lumber, plywood and wood pulp; and the conversion of primary timber products to secondary or final products such as pallets, furniture and paper products.

Forest Lands:

Land at least 10 percent stocked by tree stands of any size or that formerly had such tree cover and that will be regenerated with trees.

Forest Practices:

All activities involved with the growth, harvesting and reforestation of forest tree species.

Forest Type:

A group of tree species that, because of their environmental requirements, commonly grow together. Examples of forest types are the Douglas-fir/hemlock type or the spruce/fir type. Also, a descriptive term used to group stands with similar composition and development characteristics.


Wood used for conversion to some form of energy, primarily for residential use.

Growing Stock:

A classification of timber inventory that includes live trees of commercial species meeting specified standards of quality and vigor. When associated with volume, includes only trees 5.0 inches in diameter breast-height (DBH) and larger.


Removing mature trees to improve the growing conditions for other trees in the forest and to provide raw materials for human use. (Click here go to Harvest Options page.)

Log Rule:

A table that expresses log volume based on log diameter and length. The Scribner Decimal C Rule is the legal rule in Idaho.

Log Scale:

The lumber content of a log as determined by a log rule.

Natural Regeneration:

The process of forest growth, with young plants sprouting from seeds that have been naturally dropped upon the soil.

Nonindustrial Private Forest:

Forestland owned by farmers, ranchers and all other individuals and corporations that do not operate wood-processing plants.

Non-Structural Panels:

Hardwood panels, hardboard, insulating board, particleboard and medium-density fiberboard used in construction.


Roundwood, whole-tree chips or wood residues that are used for the production of wood pulp.


The act of replanting or reseeding a forest area to replace trees removed by harvest or destroyed by fire, wind or disease.


Logs, bolts or other round sections cut from growing stock and non-growing stock sources: includes sawlogs, pulpwood, pilings and poles.

Salvage Cutting:

The removal of dead trees or trees being damaged or killed by injurious agents other than competition, to recover value that would otherwise be lost.


A log usually used in the manufacture of lumber of veneer, meeting minimum standards of diameter, length and defect.


A small tree which has been produced from a seed.


The art, science and practice of controlling the establishment, growth, composition, health and quality of forests and woodlands. Silviculture entails the manipulation of forest and woodland vegetation in stands and on landscapes to meet the diverse needs and values of landowners and society on a sustainable basis.


A contiguous group of trees sufficiently uniform in age class distribution, composition and structure, and growing on a site of sufficiently uniform quality, to be a distinguishable unit.

Structural Panels:

Softwood plywood, waferboard, oriented board, particleboard and composite board used in construction.

Sustained Yield:

Harvest practices which, over time, ensure that the rate of timber harvest does not exceed the rate of timber growth.


A cutting made to reduce stand density of trees primarily to improve growth, enhance forest health or to recover potential mortality.

Timber Growth:

Represents a purely biological measure of timber output. It is the amount of timber produced in the forest and stored “on the stump” for both present and future consumption.

Timber Mortality:

The volume of sound trees that die annually from natural causes such as insects, disease, competition from other trees, fire and windthrow.


The uprooting and overthrowing of trees by the wind.