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abiotic a) Referring to the absents of living organisms (FSEIS Feb. 94, Glossary-1)

b) Non-living.  Climate is an abiotic component of ecosystems. (FS People's Glossary of Eco Mgmt Terms)

adaptive management

a) The process of implementing policy decisions as scientifically driven management experiments that test predictions and assumptions in management plans, and using the resulting information to improve the plans.  (FEMAT, IX-1)

b) A continuing process of action-based planning, monitoring, researching, evaluating, and adjusting with the objectives of improving implementation and achieving the goals of the selected alternative. (FSEIS Feb. 94, Glossary-1)

c) A type of natural resource management that implies making decisions as part of an on-going process.  Monitoring the results of actions will provide a flow of information that may indicate the need to change a course of action.  Scientific findings and the needs of society may also indicate the need to adapt resource management to new information. (FS People's Glossary of Eco Mgmt Terms)

aerial logging Removing logs from a timber harvest area by helicopter.  Fewer roads are required, so the impact to the area is minimized. (FS People's Glossary of Eco Mgmt Terms)
affected environment The natural environment that exists at the present time in an area being analyzed (FS People's Glossary of Eco Mgmt Terms)
age class a) A management classification using the age of a stand of trees. (FEMAT, IX-1)

b) An are grouping of trees according to an interval of years, usually 20 years.  A single age class would have trees that are within 20 years of the same are such as 1-20 years or 21-40 years. (FS People's Glossary of Eco Mgmt Terms)

airshed A geographic area that shares the same air mass due to topography, meteorology, and climate.  (FEMAT, IX-2)
allotment (range allotment) The area designated for use by a prescribed period of time,  Though an entire Ranger District may be divided into allotments, all land will not be grazed, because other uses, such as recreation of tree plantings, may be more important at a given time. (FS People's Glossary of Eco Mgmt Terms)
anadromous fish Fish that are born and rear in freshwater, move to the ocean to grow and mature, and return to freshwater to reproduce.  Salmon, steelhead, and shad are examples. (FEMAT, IX-2)
aspect The direction a slope faces with respect to the cardinal compass points. (FEMAT, IX-2)  A hillside facing east has an eastern aspect
ASQ (allowable sale quantity) The gross amount of timber volume, including salvage, that may be sold annually from a specified area over a stated period in accordance with management plans of the Forest Service or Bureau of Land Management.  Formerly referred to as "allowable cut." (FEMAT, IX-2)
aquifer A body of rock that is saturated with water or transmits water.  When people drill wells, they tap water contained within an aquifer. (FS People's Glossary of Eco Mgmt Terms)
AUM (animal unit month) The amount of forage necessary for the sustenance of one cow or its equivalent for 1 month. (FEMAT, IX-2)
bark beetle An insect that bores through the bark on forest trees to eat the inner bark and lay its eggs.  Bark beetles are important killers of forest trees. (FS People's Glossary of Eco Mgmt Terms)
basal area The area of the cross section of a tree stem including the bark, near its base, generally at breast height, or 4.5 feet above the ground. (FEMAT, IX-3).  Basal area is a way to measure how much of a site is occupied by trees.  The term basal area is often used to describe the collective basal area of trees per acre. (FS People's Glossary of Eco Mgmt Terms)
big game Large mammals that are hunted by humans.  Big game include elk, black tailed deer, and black bear. (FEMAT, IX-3)
biological control The use of natural means to control unwanted pests.  Examples include introduction of naturally occurring predators such as wasps, or hormones that inhibit the reproduction of pests.  Biological controls can sometimes be alternatives to mechanical or chemical means. (FS People's Glossary of Eco Mgmt Terms)
biological diversity The variety of life forms and processes, including a complexity of species, communities, gene pools, and ecological functions. (FEMAT, IX-3)
biomass The total quantity (at any given time) of living organisms of one or more species per unit of space (species biomass), or of all the species in a biotic community (community biomass). (FEMAT, IX-4)
biome The complex of living communities maintained by the climate of a region and characterized by a distinctive type of vegetation.  Examples of biomes in North America include the tundra, desert, prairie, and the western coniferous forests. (FS People's Glossary of Eco Mgmt Terms)
biota The plant and animal life of a particular region. (FS People's Glossary of Eco Mgmt Terms)
biotic Living.  Green plants and soil microorganisms are biotic components of ecosystems. (FS People's Glossary of Eco Mgmt Terms)
BMP (best management practices) Methods, measures, or practices designed to prevent or reduce water pollution.  Not limited to structural and nonstructural controls, and procedures for operations and maintenance.  Usually, BMPs are applied as a system of practices rather than a single practice. (FEMAT, IX-3)
board foot Lumber or timber measurement term.  The amount of wood contained in an unfinished board 1 inch thick, 12 inches long, and 12 inches wide. (FEMAT, IX-4)
broadcast burn allowing a prescribed fire to burn over a designated area within well-defined boundaries for reduction of fuel hazard or as a silvicultural treatment, or both. (SAT, p. 500)
browse Twigs, leaves and young shoots of trees and shrubs that animals eat.  Browse is often used to refer to the shrubs eaten by big game, such as elk and deer. (FS People's Glossary of Eco Mgmt Terms)
buffer a) Used in the context of marbled murrelet standards and guidelines, a forested area located adjacent to suitable (nesting) marbled murrelet habitat that reduces dangers of having sharply contrasting edges or clearcuts next to such habitat.  Dangers include risk of wind damage to nest trees and young, increased predation, and loss of forest interior conditions. (FEMAT, IX-4)

b) A land area the is designated to block or absorb unwanted impacts to the area beyond the buffer.  Buffer strips along a trail could block views that may be undesirable.  Buffers may be set aside next to wildlife habits to reduce abrupt change to the habitat. (FS People's Glossary of Eco Mgmt Terms)

cable logging Logging that involves the transport of logs from stump to collection points by means of suspended steel cables.  Cable logging reduces the need for construction of logging roads. (FS People's Glossary of Eco Mgmt Terms)
canopy A layer of foliage in a forest stand.  This most often refers to the uppermost layer of foliage, but it can be used to describe lower layers in a multistoried stand. (FEMAT, IX-4)
cavity A hole in a tree often used by wildlife species, usually birds, for nesting roosting, and reproduction. (FS People's Glossary of Eco Mgmt Terms)
chemical control The use of pesticides and herbicides to control pests and undesirable plant species. (FS People's Glossary of Eco Mgmt Terms)
clear cut A harvest in which all or most all of the trees are removed in one cutting. (FEMAT, IX-5)
climax The culmination stage in plant succession for a given site where the vegetation has reached a highly stable condition.  (FEMAT, IX-5)
coarse filter management Land management that addresses the needs of all associated species, communities, environments and ecological processes in a land area.  (see fine filter management.) (FS People's Glossary of Eco Mgmt Terms)
collector roads These roads serve small land areas and are usually connected to a Forest System Road, a county road, or a state highway. (FS People's Glossary of Eco Mgmt Terms)
composition What an ecosystem is composed of.  Composition could include water, minerals, trees, snags, wildlife, soil, microorganisms, and certain plant species. (FS People's Glossary of Eco Mgmt Terms)

A tree belonging to the order Gymnospermae, comprising a wide range of trees that are mostly evergrees.  Conifers bear cones (hence, confierous) and needle-shaped or scalelike leaves. (FEMAT, IX-7)

connectivity (of habitats) a) A measure of the extent to which conditions among late-successional and old-growth forest areas provide habitat for breeding, feeding, dispersal, and movement of late-successional old-growth associated wildlife and fish species.  Also See Late-Successional/Old-Growth Forest. (FEMAT, IX-7)

b) The linkage of similar but separated vegetation stands by patches, corridors, or "stepping stones" of like vegetation.  This term can also refer to the degree to which similar habitats are linked. (FS People's Glossary of Eco Mgmt Terms)

consumptive use Use of resources that reduces the supply, such as logging and mining. (FS People's Glossary of Eco Mgmt Terms)
contour A line drawn on a map connecting points of the same elevation. (FS People's Glossary of Eco Mgmt Terms)
corridor a) A defined tract of land, usually linear, through witch a species must travel to reach habitat suitable for reproduction and other life-sustaining needs. (FEMAT, IX-7)

b) Elements of the landscape that connect similar areas,  Streamside vegetation may create a corridor of willows and hardwoods between meadows where wildlife feed. (FS People's Glossary of Eco Mgmt Terms)

cover Vegetation used by wildlife protection from predators, or to mitigate weather conditions, or to reproduce.  May also refer to the protection of the soil and the shading provided to herbs and forbs by vegetation. (FEMAT, IX-8)
cover forage ratio The ratio of hiding cover to foraging areas for wildlife species. (FS People's Glossary of Eco Mgmt Terms)
cover type (forest cover type) Stands of a particular vegetation type that are composed of similar species.  The aspen cover type contains plants distinct from the pinyon-juniper cover type. (FS People's Glossary of Eco Mgmt Terms)
created opening An opening in the forest cover created by the application of even-aged silvicultural practices. (FS People's Glossary of Eco Mgmt Terms)
critical habitat

Under the Endangered Species Act, critical Habitat is defined as (1) the specific areas within the geographic area occupied by a federally listed species on which are found physical and biological features essential to the conservation of the species, and that may require special management considerations or protection; and (2) specific areas outside the geographic area occupied by a listed species, when it is determined that such areas are essential for the conservation of the species. (FEMAT, IX-8)

crown The upper part of a tree or other woody plant that carries the main system of branches and the foliage. (FEMAT, IX-8)
crown height The distance from the ground to the base of the crown of a tree. (FS People's Glossary of Eco Mgmt Terms)
cultural resources Any definite location of past human activity identifiable through field survey, historical documentation, or oral evidence.  This includes archaeological or architectural sites, structures, or places and places of traditional cultural or religious importance to specific groups whether or not represented by physical remains. (FEMAT, IX-8)
cumulative effects Impacts of the environment resulting from the incremental effects of the action when added to effects of past, present, and reasonable foreseeable future actions regardless of the agency (federal or nonfederal) or person undertaking such other actions.  Cumulative effects can result from individually minor, but collectively significant, actions taking place over a period of time. (FEMAT, IX-8)
dbh See diameter at breast height.
decision criteria The rules and standards used to evaluate alternatives to a proposed action on National Forest land.  Decision criteria are designed to help a decision makers identify a preferred choice from the array of alternatives. (FS People's Glossary of Eco Mgmt Terms)
decking area A site where logs are collected after they are cut and before they are taken to the landing area where they are loaded for transport. (FS People's Glossary of Eco Mgmt Terms)
DEIS (Draft Environmental Impact Statement) The draft statement of environmental effects that is required for major federal action under Section 102 of the National Environment Policy Act, and released to the public and other agencies for comment and review. (FEMAT, IX-10)
desired future condition An explicit description of the physical and biological characteristics of aquatic and riparian environments believed necessary to meet fish, aquatic ecosystem, and riparian ecosystem objectives. (FEMAT, IX-9)
developed recreation a) A site developed with permanent facilities designed to accommodate recreation use. (FEMAT, IX-9)

b) Recreation that requires facilities that, in turn, result in concentrated use of the area.  For examples skiing requires ski lifts, parking lots, buildings, and roads.  Campgrounds require roads, picnic tables, and toilet facilities. (FS People's Glossary of Eco Mgmt Terms)

diameter at breast height The diameter of a tree 4 and 1/2 feet above the ground on the uphill side of a tree. (FEMAT, IX-9)
dispersed recreation Outdoor recreation in which visitors are diffused over relatively large areas.  Where facilities or developments are provided, they are primarily for access and protection of the environment rather than comfort or convenience of the user. (FEMAT, IX-10)
disturbance A force that causes significant change in structure and/or composition through natural events such as fire, flood, wind, or earthquake, mortality caused by insect or disease outbreaks, pr by human-caused events, e.g., the harvest of forest products. (FEMAT, IX-10)
Last updated
 Monday, July 21, 2003

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