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early successional forest Forest seral stages younger than mature and old-growth age classes. (FSEIS Feb. 94, Glossary-5)
ecology The interrelationships of living things to one another and the their environment, or the study of these interrelationships. (FS People's Glossary of Eco Mgmt Terms)
ecoregion An area over which the climate is sufficiently uniform to permit development of similar ecosystems on sites that have similar properties.  Ecoregions contain many landscapes with different spatial patterns of ecosystems. (FS People's Glossary of Eco Mgmt Terms)
ecosystem a) A unit comprising interacting organisms considered together with their environment (e.g., marsh, watershed, and lake ecosystems). (FEMAT, IX-10)

b) An ecological system, consisting of living organisms and nonliving components, as well as, flows and other processes, and the links and interrelationships among them from which "systems" properties, such as resilience and ecosystem function, emerge.  While an ecosystem can occur on any scale, it is often convenient (for analysis, management, or other purposes) to delineate it as a geographic area, with its boundaries demarcating an area where links within the system are stronger than links with adjacent systems. (Ecosystem Analysis at the Watershed Scale v 2.2, p. 24)

ecosystem approach A strategy or plan to manage ecosystems to provide for all associated organisms, as opposed to a strategy or plan for managing individual species (S&G Jan 2001, p. 74)
ecosystem management The use of an ecological approach in land management to sustain diverse, healthy, and productive ecosystems.  Ecosystem management is applied at various scales to blend long-tem societal and environmental values in a dynamic manner that may be adapted as more knowledge is gained thought research and experience. (FSEIS Feb. 94, Glossary-5)
ecotone a) A zone of intergradation between ecological communities. (FSEIS Feb. 94, Glossary-5)

b) The transition zone between two biotic communities, such as between the Ponderosa pine forest type and the mixed conifer forest, which is found at higher elevations than the pine. (FS People's Glossary of Eco Mgmt Terms)

ecotype A population of a species in a given ecosystem that is adapted to a particular set of environmental conditions. (FS People's Glossary of Eco Mgmt Terms)
edge Where plant communities meet or where successional stages or vegetation conditions with plant communities come together. (FEMAT, IX-11)
element (of ecosystems) An identifiable component, process, or condition of an ecosystem. (FS People's Glossary of Eco Mgmt Terms)
endangered species Any species of plant or animal defined through the Endangered Species Act as being in danger of extinction throughout all or a significant portion of its range, and published in the Federal Register. (FEMAT, IX-11)
endemic or endemism Unique to a specific locality or the condition of being unique to a specific locality. (FSEIS Nov. 2000, Vol. I p.472)
environmental analysis An analysis of alternative actions and their predictable long and short-term environmental effects, incorporating physical, biological, economic and social considerations.  (FEMAT, IX-11)
environmental assessment A systematic analysis of site-specific activities used to determine whether such activities have a significant effect on the quality of the human environment and whether a formal environmental impact statement is required; and to aid an agency's compliance with the National Environmental Policy Act when no environmental impact statement is necessary. (FEMAT, IX-11)
Environmental Impact Statement (EIS) A statement of the environmental effects of a proposed action and alternatives to it.  It is required for major federal actions under Section 102 of the National Environmental Policy Act (NEPA), and released to the public and other agencies for comment and review.  It is a formal document that must follow the requirements of NEPA, the CEQ guidelines, and directives of the agency responsible for the project proposal. (S&G Jan 2001, p. 75)
ephemeral streams Streams that contain running water only sporadically, such as during and following storm events. (FEMAT, IX-11)
erosion The wearing away of the land surface by wind and water. (FS People's Glossary of Eco Mgmt Terms)
escape cover Vegetation of sufficient size and density to hide an animal, or an area used by animals to escape from predators. (FS People's Glossary of Eco Mgmt Terms)
even-aged management A silvicultural system which creates forest stands that are primarily of a single are or limited range of ages.  Creation of even-aged stands may be accomplished through the clear-cut, seed tree or shelterwood methods. (FSEIS Feb. 94, Glossary-6)
fauna The animal life of a region or geological period. (FSEIS Feb. 94, Glossary-6)
felling Cutting down trees. (FS People's Glossary of Eco Mgmt Terms)
final cut The removal of the last seed bearers or shelter trees after regeneration of new trees has been established in a stand being managed under the shelterwood system of silviculture. (FS People's Glossary of Eco Mgmt Terms)
fine filter management Management that focuses on the welfare of a single or only a few species rather than the broader habitat or ecosystem.  (see coarse filter management.) (FS People's Glossary of Eco Mgmt Terms)
fire cycle The average time between fires in a given area. (FS People's Glossary of Eco Mgmt Terms)
fire regime The characteristic frequency extent, intensity, severity, and seasonality of fires in an ecosystem. (FEMAT, IX-12)
fisheries habitat Streams, lakes, and reservoirs that support fish, or have the potential to support fish. (FS People's Glossary of Eco Mgmt Terms)
flood plain a) Level lowland bordering a stream or river onto which the flow spreads at flood stage. (FEMAT, IX-13)

b) A lowland adjoining a watercourse.  At a minimum, the area is subject to a 1% or greater chance of flooding in a given year. (FS People's Glossary of Eco Mgmt Terms)

flora The plant life of a region or geological period. (FSEIS Feb. 94, Glossary-7)
forage All browse and non-woody plants that are eaten by wildlife and livestock. (FS People's Glossary of Eco Mgmt Terms)
forbs A broadleaf plant that has little or no woody material in it. (FS People's Glossary of Eco Mgmt Terms)
foreground The part of a scene or landscape that is nearest to the viewer. (FS People's Glossary of Eco Mgmt Terms)
forest cover type See cover type.
forest health A measure of the robustness of forest ecosystems.  Aspects of forest health include biological diversity; soil, air and water productivity; natural disturbances; and the capacity of the forest to provide a sustaining flow of goods and services for people. (FS People's Glossary of Eco Mgmt Terms)
Forest Roads and Trails Roads and trails under the jurisdiction of the Forest Service. (FS People's Glossary of Eco Mgmt Terms)
Forest Supervisor The official responsible for administering National Forest lands on an administrative unit, usually one or more National Forests.  The Forest Supervisor reports to the Regional Forester. (FS People's Glossary of Eco Mgmt Terms)
fragmentation a) The process of reducing size and connectivity of stands that compose a forest. (FEMAT, IX-13)

b) The splitting or isolating of patches of similar habitat, typically forest cover, but including other types of habitat.  Habitat can be fragmented naturally or from forest management activities, such as clear-cut logging. (FS People's Glossary of Eco Mgmt Terms)

frost heave A land surface that is pushed up by the accumulation of ice in the underlying soil. (FS People's Glossary of Eco Mgmt Terms)
fuels Plants and woody vegetation, both living and dead, that are capable of burning. (FS People's Glossary of Eco Mgmt Terms)
fuels management the treatment of fuels that would otherwise interfere with effective fire management or control.  For instance, prescribed fire can reduce the amount of fuels that accumulate on the forest floor before the fuels become so heavy that a natural wildlife in the area would be explosive and impossible to control. (FS People's Glossary of Eco Mgmt Terms)
fuelwood Wood cut into short lengths for burning. (FS People's Glossary of Eco Mgmt Terms)
function All the processes within an ecosystem through which the elements interact, such as succession, the food chain, fire, weather, and the hydrologic cycle. (FS People's Glossary of Eco Mgmt Terms)
game species Any species of wildlife or fish that is harvested according to prescribed limits and seasons. (FS People's Glossary of Eco Mgmt Terms)
geomorphic process Processes that change the form of the earth, such as volcanic activity, running water, and glacial action. (FS People's Glossary of Eco Mgmt Terms)
geomorphology The science that deals with the relief features of the earth's surface. (FS People's Glossary of Eco Mgmt Terms)
GIS (geographic information systems) a) A computer system capable of storing and manipulating spatial (i.e. mapped) data. (FEMAT, IX-14)

b) GIS is both a database designed to handle geographic data as well as a set of computer operations that can be used to analyze the data.  In a sense, GIS can by thought of as a higher order map. (FS People's Glossary of Eco Mgmt Terms)

ground fire A fire that burns along the forest floor and does not affect trees with thick bark or high crowns. (FS People's Glossary of Eco Mgmt Terms)
ground water The supply of fresh water under the earth's surface in an aquifer or in the soil. (FS People's Glossary of Eco Mgmt Terms)
group selection cutting a) Removal of groups of trees ranging in size from a fraction of an acre up to about 2 acres.  Area cut is smaller than the minimum feasible under even-aged management for a single stand. (FEMAT, IX-14)

b) A method of tree harvest in which trees are removed periodically in small groups.  This silvicultural treatment results in small openings that form mosaics of age class groups in the forest. (FS People's Glossary of Eco Mgmt Terms)

habitat The place where a plant or animal naturally or normally lives and grows. (FEMAT, IX-14)
habitat capability The estimated number of pairs of spotted owls that can be supported by the kind, amount, and distribution of suitable habitat in the area.  As used in the Final Draft Recovery Plan for the Northern Spotted Owl, this means the same as capability to support spotted owl pairs. (FEMAT, IX-14)
habitat diversity A number of different types of wildlife habitat within a given area. (FEMAT, IX-14)
habitat diversity index A measure of improvement in habitat diversity. (FS People's Glossary of Eco Mgmt Terms)
habitat type A way to classify land area.  A habitat type can support certain climax vegetation, both tree and undergrowth species.  Habitat typing can indicate the biological potential of a site. (FS People's Glossary of Eco Mgmt Terms)
hiding cover Generally, and vegetation used by wildlife for security or to escape from danger.  More specifically, and vegetation capable of providing concealment (e.g., hiding 90 percent of an animal) from human view at a distance of 200 feet or less. (FEMAT, IX-15)
horizontal diversity The distribution and abundance of plant and animal communities and successional stages across an area of land.  The greater the numbers of communities, the higher the degree of horizontal diversity. (FEMAT, IX-15)
hydrologic cycle Also called the water cycle, this is the process of water evaporating, condensing, falling to the ground as precipitation, and returning to the ocean as run-off. (FS People's Glossary of Eco Mgmt Terms)
hydrology The science dealing with the study of water on the surface of the land, in the soil and underlying rocks, and in the atmosphere. (FS People's Glossary of Eco Mgmt Terms)
Last updated
 Monday, July 21, 2003

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