Silviculture - The science of tending forest stands.

Forest Types - Association of tree species that occur commonly due to similar site requirements.

Canopy - The continuous cover formed by tree crowns in a forest.

Mature - In financial terms, the age at which a tree, or stand, reaches its highest or targeted value.  Can also refer to non-financial and somewhat subjective criteria.

Even Aged - Management scheme in which all trees of the desired species are the same age.

Uneven Aged (Multiple aged) - Process through select cutting and natural regeneration which causes there to be multiple ages of desirable trees in an area.

Sustained Yield - A management concept in which the volume of timber removed equals growth of the forest.

Multiple Use - Actively managing the forest for more than one primary use.

Dominant - Trees that extend above surrounding individuals and capture sunlight from above and around the crown.

Co-Dominant - Trees that extend the crown into the canopy and receive direct sunlight from above only.

Suppressed - Trees that are completely overtopped and are characterized by low growth rate and low vigor.

Disturbance - A natural or human-induced environmental change that affects species and structural composition in a stand.

Succession - The natural process of replacement of one plant community by another over time.

Pioneer Species - The earliest species in the process of succession.

Climax - The fully mature plant community based on natural succession of a site. 

Site Index - A measure of the quality of a site based on the height of dominate trees at a specified age (usually 25 or 50 years), depending on the species.

Prescribed Burn - A fire intentionally started for specific forest management practices.

Wildfire - An unintentional fire, whether started by accident or by arson.

Edge or Edge Effect - Boundary between two different vegetative communities, for example, a field and a wooded area.  Of particular interest to wildlife enthusiasts.

BMP - Best Management Practices.  A voluntary set of standards applicable to forest practices intended to minimize site damage, protect water quality and maintain productivity of the forest.

SMZ - Streamside Management Zone.  An area adjacent to significant drains that is managed to protect or improve water quality.

GPS - Global Positioning Satellite.

GIS - Geographic Information System.

TSI - Timber Stand Improvement.  Practices that increases the value or rate of value growth in a given stand.

NIPF - Non-industrial private forestland.  Forestland owned by private individual, group or corporation not involved in wood processing.

NRCS - Natural Resource Conservation Service.  Branch of US Department of Agriculture (USDA) that coordinates and implements soil conservation practices on private lands.

CES - Cooperative Extension Service.  Links university research with the end users in the field.

FSA - Farm Services Agency.  Branch of the USDA that administers cost-sharing programs.

Acre - A measure of area, 43,560 square feet.

Hectacre - A measure of area, used in many other countries, often found in trade journals.  About 2.47 acres.

Diameter Breast Height (DBH) - Standard measure of a tree's diameter about 4½ feet above the ground.

Cruise - A forest survey used to obtain inventory information and develop a management plan.

Log Rule (Log Scale) - A method for calculating wood volume in a tree or log by using its diameter and length.  Doyle scale typically used locally.

Board Feet - A measure of volume in a tree, log or board.  Based on sawn lumber dimensions, measures a board 1 foot by 1 foot by 1 inch, or some combination that yields 144 cubic inches.  Typically referred to in units of one thousand board feet.

Conversion Rate - Number of tons per volume unit (board foot or cord)

Merchantable height - The point on a tree stem to which the stem is salable.  Can be limited by diameter or defect.

Chain - A measure of length, 66 feet.

Rod - A measure of length, 16½ feet.  Often used by the pipeline industry.

Diameter Tape - A tape measure used on the circumference of a tree but calibrated to directly give the diameter.

Cord - A unit of wood containing 128 cubic feet. (4 x 4 x 8 feet).

Basal Area - The cross-sectional area of the trunk 4½ feet above the ground.  Typically expressed as a per acre measure of forest density.

Clearcut - The harvest of all the trees in an area.

Thinning - A partial cut in an immature, overstocked stand of trees.

Shelterwood Cut - Process of removing all the merchantable trees over several cuts, with the goal of natural regeneration.

Seed-tree Cut - The harvest of all the trees in an area except for a few desirable individuals that provide seed for the next forest. 

Windthrow - A tree felled by wind.  A problem with shallow-rooted trees and in areas where cutting has reduced stand density.

Diameter Cut - Harvest of all trees over a certain diameter in an area.

Lump-sum Sale - The sale of timber in which the price is agreed upon before any trees are removed.

Unit Sale (or pay as cut) - The buyer makes regular payments based on mill receipts.

Sealed Bid Sale - A timber sale, usually offered through a consulting forester, in which buyers submit sealed bids.  Can be lump-sum or pay as cut.

Negotiated Sale - A timber sale in which the buyer and the seller negotiate an arm's length stumpage price.  Can be lump-sum or pay as cut.

Stumpage Price - The price paid for standing forest trees.