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Glossary

Adaptive Management Areas (AMA)
A Northwest Forest Plan Option 9 designation for certain lands in National Forests. In the Klamath-Siskiyou, we have two AMAs: the Applegate AMA and the Hayfork AMA. The Option 9 definition of an AMA is: "Adaptive Management Areas are landscape units designated to encourage the development and testing of technical and social approaches to achieving desired ecological, economic, and other social objectives." In other words, the local community is supposed to have a greater say in what happens there, and its objective is to test other Option 9 land designations (such as matrix) as to the effect of allowable management activities on the ecosystem. The Applegate AMA is 324,680 acres in southern Oregon and emphasizes developing and testing a variety of practices for sustainable forests and communities. The BLM proposed to eliminate the Applegate AMA in their draft Western Oregon Plan Revision, released in 2007. The Hayfork AMA is 350,000-acres in northern California and focuses on the development of innovative approaches to natural resources management, including timber production, maintenance of mature forests and quality riparian habitat, and the development of new social and economic relationships between and among communities and forests.
Age class
An age 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 age, such as 1-20 years or 21-40 years.
Allotment (range allotment)
The area designated for use by a prescribed number of livestock for a prescribed period of time. 
Anadromous fish
Species of fish that are born in freshwater streams, migrate and mature in the sea and return tho their natal streams to spawn and die. Most species are now endangered, such as Coho salmon.
Aquatic Conservation Strategy
A component of the Northwest Forest Plan. Designed to resore and maintain the ecological health of watersheds and aquatic ecosystems.
Area of Critical Environmental Concern (ACEC)
Lands where special management attention is needed to protect and prevent damage to important historic, cultural, or scenic values, fish, and wildlife resources or other natural systems or processes or to protect life and provide safety from natural hazards.
Aspect
The direction a slope faces. A hillside facing east has an eastern aspect.
ASQ (allowable sale quantity)
The amount of timber that may be sold within a certain time period from an area. The areas and the time period are specified in the Forest Plan.
Basal area
The area of the cross section of a tree trunk near its base, usually 4 and 1/2 feet above the ground. 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.
Biological diversity
The number and abundance of species found within a common environment. This includes the variety of genes, species, ecosystems, and the ecological processes that connect everything in a common environment.
Biomass
Total mass of living organisms present in a given area. It may be used to describe the mass of a particular species (such as earthworm biomass), for a general category (such as herbivore biomass - animals that eat plants), or for everything in a habitat. Plant biomass can be changed into liquid or gaseous fuels to generate electricity or heat, or to fuel internal combustion engines.
BMP (Best Management Practices)
Methods, measures, or practices designed to prevent or reduce water pollution.
Board foot
A measurement term for lumber or timber. It is the amount of wood contained in an unfinished board 1 inch thick, 12 inches long, and 12 inches wide. Roughly, about four million board feet (5 mmbf) can be extracted out of about 100 acres of old-growth forests in the Umpqua Basin. 
Broadcast burn
A prescribed fire that burns a designated area. This is usually used after a clear-cut deforestation project to remove debris. 
Buffer
A land area that is designated to block or absorb unwanted impacts to the area beyond the buffer. For instance, deforested areas are usually buffered from roads used by tourists. 
Bureau of Land Management (BLM)
In the Department of the Interior, the BLM manages our public lands - usually range lands in the West. However, in western Oregon and Washington, the BLM also manages forested lands. This is because the O&C railroads were given lands back in the 1800s to build a railroad, and when they failed, the land reverted back to the federal government. These are called O&C lands, now managed by the BLM. They were a superb temperate rainforest because of their proximity to the Pacific Ocean. They supported huge trees and a vast array of wildlife. In general, they are located at lower elevations than Forest Service lands. Much of O&C land is spotted owl and marbled murrelet country. Because the O&C railroad company was given every other section in the area, BLM now manages a checkerboard configuration of public lands. Private timber industry holdings are usually the interspersed section.
Cable logging
Logging that involves the transport of logs from stump to collection points (landings) by means of suspended steel cables. Cable logging leaves compacted skidding scares forever on the landscape.
Canopy
The part of any stand of trees represented by the tree crowns. It usually refers to the uppermost layer of foliage, but it can be use to describe lower layers in a multi-storied forest.
Cavity
A hole in a tree often used by wildlife species, usually birds, for nesting, roosting, and reproduction.
Checkerboard Ownership
A land ownership pattern in which every other section (square mile) is in federal ownership as a result of federal land grants to early western railroad companies.
Clearcut
A harvest in which all or almost all of the trees are removed in one entry. Also called 'deforestation'.
Conifer
A tree that produces cones, such as a pine, spruce, or fir tree. Most conifer trees are 'evergreen', but a few, such as Larch, are deciduous.
Connectivity (of habitats)
The linkage of similar but separated vegetation stands by corridors of like vegetation. We often use this term to see if old-growth forests are connected to each other, allowing gene pools to mix, or if they are fragmented into islands by clearcuts and road-building.
Corridor
Elements of the landscape that connect similar areas, such as old-growth forests.
Critical habitat
Areas designated for the survival and recovery of federally listed threatened or endangered species (under the Endangered Species Act).
Cubic Foot
A unit of solid wood, one foot square and one foot thick.
Cultural resource
The remains of sites, structures, or objects used by people in the past; this can be historical or pre-historic.
Cumulative effects
Effects on the environment that result from separate, individual actions that collectively become significant over time.
DBH (diameter at breast height)
The diameter of a tree 4 and 1/2 feet above the ground on the uphill side of the tree.
DEIS (Draft Environmental Impact Statement)
The draft version of the Environmental Impact Statement that is released to the public and other agencies for review and comment, as part of the National Environmental Policy Act.
Density Management
The cutting of trees for the purpose of widening their spacing so that growth of remaining trees can be accelerated.
Desired future condition
Land or resource conditions that are expected to result if goals and objectives are fully achieved.
Disturbance
Any event, such as forest fire, insect infestations or clearcut that alter the structure, composition, or functions of an ecosystem.
Early forest succession
The biotic (or life) community that develops immediately following a clear cut or fire. For instance, grasses may be the first plants to grow in an area that was burned.
Ecology
The interrelationships of living things to one another and to their environment, or the study of these interrelationships.
Ecosystem
An arrangement of living and non-living things and the forces that move among them. Living things include plants and animals. Non-living parts of ecosystems may be rocks and minerals. Weather and wildfire are two of the forces that act within ecosystems.
Edge effect
The effect on the surrounding forests from the edges of a clearcut. Common edge effects include trees blown down, spreading root rots and other diseases, and invasive weeds. Edge effects often travel very far into the surrounding interior forests.
Endangered species
A plant or animal that is in danger of extinction throughout all or a significant portion of its range. Endangered species are identified by the Secretary of the Interior in accordance with the Endangered Species Act of 1973, but most often brought to their attention by citizen groups.
Endemism
Endemism describes species that are native to a particular geographic area or continent. The Klamath-Siskiyou has high levels of plant endemism, such as the Gentner's fitillary.
Environmental assessment
A brief version of an Environmental Impact Statement, which are NEPA required documents. An analysis of alternative actions and their predictable long and short- term environmental effects. 
Environmental Impact Statement - (EIS)
A NEPA required document. A statement of environmental effects of a proposed action and alternatives to it. In general, an action requires an EIS if it is a large project, whereas small projects only require an EA.
Even aged management
Timber management actions that result in the creation of stands of trees in which the trees are essentially the same age. This is accomplished by clearcutting and conversion to tree plantations.
Fire cycle
The average time between fires in a given area. In the Klamath-Siskiyou, natural fire cycles vary greatly - between 10 and 140 years - depending on vegetation and rainfall. Significant ecological problems have resulted from the suppression of natural fire cycle.
Fire regime
The characteristics of fire in a given ecosystem, such as the frequency, predictability, intensity, and seasonality of fire.
Flora
The plant life of an area.
FONSI - Finding of no significant impact.
A declaration by an agency that a proposed action will not harm the environment.
Fragmentation
The splitting or isolating of patches of similar habitat, such as old-growth forests. Habitat is usually fragmented from forest management activities, such as clearcut logging and road-building.
Fuels
Plants and woody vegetation, both living and dead, that are capable of burning.
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 wildfire in the area would be explosive and impossible to control.
GIS (geographic information systems)
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 be thought of as a higher order map.
Green tree retention
A Northwest Forest Plan Option 9 standard and guideline, it requires that 15% of a clearcut unit be left intact in mostly aggregate stands (clumped) with a few dispersed trees. For BLM, the green tree retention is specified at 6-8 trees per acre (general forest) or 12 to 18 TPA for Connectivity/Diversity Blocks. The BLM's 2007 WOPR proposes to reduce or eliminate green tree retention. 
Ground fire
A fire that burns along the forest floor and does nor affect trees with thick bark or high crowns. Ground fires do not kill most of the overstory trees, and in general, protect the larger trees from hotter fires.
Group selection
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.
Habitat
The area where a plant or animal lives and grows under natural conditions.
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.
Indicator species
A plant or animal species related to a particular kind of environment. Its presence indicates that specific habitat conditions are also present. The spotted owl is an indicator species of old-growth forest ecosystems.
Instream flow
The quantity of water necessary to meet seasonal stream flow requirements to accomplish the purposes of the National Forests, including, but not limited to fisheries, visual quality, and recreational opportunities.
Interior forest
A forest area that is not influenced by edge effects.
Intermittent stream
A stream that flows only at certain times of the year when it receives water from streams or from some surface source, such as melting snow.
Invasive species
An alien species whose introduction does, or is likely to, cause economic or environmental harm or harm to human health. Example: tui chub.
Jeopardy
A finding under the Endangered Species Act that the action of a federal agency is likely to jeopardize the continued existence of a threatened or endangered species.
Key watershed
A Land Use Allocation used in the Nortwest Forest Plan. A watershed containing: (1) habitat for potentially threatened species or stocks or anadromous salmonoids or other potentially threatened fish, or (2) greater than six square miles with high-quality water and fish habitat.
Ladder fuels
Vegetation located below the crown level of forest trees which can carry fire from the forest floor to tree crowns. Ladder fuels may be low-growing tree branches, shrubs. or smaller trees. Practice of fire suppression over the last 100 years has resulted in a dangerous accumulation of ladder fuels.
Late forest succession
The stage of forest succession in which most of the trees are mature. Old growth is a late forest succession. Compare with early forest succession.
Late-successional, old-growth (LSOG) habitat
A forest in its mature or old-growth stage.
Late-Successional Reserve (LSR)
An Option 9 land designation (see AMA, Matrix, and Riparian Reserves). A LSR contains forests set aside from Matrix-type logging, to be held in reserve for wildlife habitat. Old clearcuts as well as old-growth forests are in LSRs. Logging is allowed if it will help the LSR reach old growth characteristics faster.
LRMP (Land and Resource Management Plan)
Also called "The Forest Plan" or "The Plan," this document guides the management of a particular National Forest and establishes management standards and guidelines for all lands of that National Forest. (For BLM, the equivalent is the RMP).
MBF
Thousand board feet. Five thousand board feet of timber can be expressed as 5M board feet.
MMBF
Million board feet. 
Macroclimate
The general, large scale climate of a large area, as distinguished from the smaller scale micro climates within it.
Matrix
Where most deforestation is allowed to take place. An Option 9 land designation. Other examples of Option 9 land designations are LSR's, AMA's, and Riparian Reserves.
Mean annual increment of growth
The total increase in size or volume of individual trees. Or, it can refer to the increase in size and volume of a stand of trees at a particular age, divided by that age in years.
Microclimate
The climate of a small site. It may differ from the climate at large of the area due to aspect, tree cover (or the absence of tree cover), or exposure to winds.
MIS (management indicator species)
A wildlife species whose population will indicate the health of the ecosystem in which it lives and, consequently, the effects of forest management activities to that ecosystem. MIS species are selected by land management agencies. 
Mosaic
Areas with a variety of plant communities over a landscape, such as areas with trees and areas without trees occurring over a landscape. Natural fires are often described to burn in a "mosaic" pattern.
Multiple use management
The management of all the various renewable surface resources of National Forest lands for a variety of purposes such as recreation, range, timber, wildlife and fish habitat, and watershed.
National Forest
193 million acres of public land administered by the USDA Forest Service (established in 1905). 
National Parks
Public lands administered by USDI National Park Service. These public lands are managed exclusively for the preservation of their natural resources. The National Park Service also manages National Monuments and Historic Sites. It is distinct from the USDA Forest Service in that logging, mining, and grazing are forbidden. 
Neotropical bird species
Birds that breed and nest in North America, but migrate each fall to warmer climates in tropical regions of Mexico, Central America, South America, and the Caribbean.
NEPA (National Environmental Policy Act)
Congress passed NEPA in 1969 to allow public input into the decision making of public resources. One of the major tenets of NEPA is its emphasis on public disclosure of possible environmental effects of any major action on public lands. Section 102 of NEPA requires a statement of possible environmental effects to be released to the public and other agencies for review and comment. 
NFMA (National Forest Management Act)
This law was passed in 1976 and requires the preparation of Regional Guides and Forest Plans.
No action alternative
Included in EAs, the most likely condition expected to exist in the future if management practices continue unchanged.
Nonpoint source pollution
Pollution whose source is not specific in location. The sources of the discharge are dispersed, not well defined, or constant. Rain storms and snowmelt often make this type of pollution worse. Examples include sediments from logging activities and runoff from agricultural chemicals and cow dung.
Notice of intent
A notice in the federal register of intent to prepare an environmental impact statement on a proposed action.
NWFP - Northwest Forest Plan
President Clinton's forest plan that put new environmental regulations into effect in the summer of 1994. Developed to ease gridlock between the courts and industry. Its emphasis was on managing federal timber in a way to prevent species extinction.
O&C Lands
Public lands granted to the Oregon and California Railroad Company and subsequently revested to the United States after fraudulent land deals.
Old-growth
Old forests often containing several canopy layers, variety in tree sizes and species, trees at least 180 to 220 years old, and standing and dead woody material.
Option 9 - (Also see NWFP)
The option chosen in the decision on how to manage public forest lands within the range of the Northern Spotted owl, and implimenated in June of 1994. It covers most federal lands west of the Casade Range to the Pacific Ocean in Washington, Oregon, and Northern California. 
ORV
Off-road vehicles, such as motorcycles, 4-wheel drive vehicles, and 4-wheelers.
Overstory
The upper canopy layer; the plants below comprise the understory.
Planning area
The area of National Forest land covered by a Regional Guide or Forest Plan.
Precommercial thinning
Removing some of the trees from a stand that are too small to be sold for lumber or house logs, so the remaining trees will grow faster, and commercially logged later.
Prescribed fire
Fire set intentionally in wildland fuels under prescribed conditions and circumstances. Prescribed fire should be used to mitigate the suppression of natural fires.
Prescription
Management practices selected to accomplish specific land and resource management objectives.
Range of variability (Also called the historic range of variability or natural range of variation.)
The range of sustainable conditions in an ecosystem is determined by time, processes (such as fire), native species, and the land itself. Ecosystems that have a 10-year fire cycle have a narrower range of variation than ecosystems with 200-300 year fire cycle.
Ranger District
The administrative sub-unit of a National Forest that is supervised by a District Ranger who reports directly to the Forest Supervisor. (See Resource Area for the BLM equivalent.)
RARE II- Roadless Area Review and Evaluation.
The national inventory of roadless and undeveloped areas within the National Forests and Grasslands.
Reforestation
The restocking of an area with forest trees, by either natural or artificial means, such as planting. All harvested units are reforested, but many fail to succeed.
Regeneration
The renewal of a tree crop by either natural or artificial means. The term is also used to refer to the young crop itself.
Regeneration harvest
A harvest method identical to clear-cutting. Usually six to twelve trees per acre remain.
Regional Ecosystem Office (REO)
Reviews, and has authority to change the standards and guidelines of Option 9. They actually recommend changes and interpretations to the Regional Interagency Executive Committee, who has responsibility for the decisions.
Regional Forester
The official of the USDA Forest Service responsible for administering an entire region of the Forest Service. The Umpqua National Forest is in Region 6.
Resource Area
The administrative sub-unit of the BLM that is supervised by a Resource Area Manager who reports directly to the District Manager. (See Ranger District for the USFS equivalent.)
Resource Management Plan (RMP)
A land use plan for BLM districts.
Riparian area
The area along a watercourse or around a lake or pond; a wet area.
Riparian Reserves
An Option 9 land designation. This is no cut buffer left along intermittent and fish bear streams. In the Umpqua basin, on the average, it is about 180 feet wide at intermittent streams, and 360 feet wide fish bearing streams. Its actual width is calculated by a multiple of a site tree.
Record of Decision (ROD)
A official document in which a deciding official states the alternative that will be implemented from a prepared EIS or EA.
Rotation
The number of years required to establish and grow timber crops to a specified condition of maturity. The rotation age for Douglas Fir in the Umpqua National Forest is 80 years.
Scoping
Part of the NEPA process to determine public opinion, receive comments and suggestions, and determine issues during the environmental analysis process. It may involve public meetings, telephone conversations, or letters.
Second growth
Forest growth that is established after some kind of interference with the previous forest crop, such as clear cutting.
Silviculture
The art and science that promotes the growth of single trees and the forest as a biological unit.
Size class
One of the three intervals of tree stem diameters used to classify timber in the Forest Plan data base. The size classes are: Seedling/Sapling (less than 5 inches in diameter); Pole Timber (5 to 7 inches in diameter); Sawtimber (greater than 7 inches in diameter)
Snag
A standing dead tree. Snags are important as habitat for a variety of wildlife species and their prey. Most snags are felled in harvest operations.
Soil compaction
The reduction of soil volume. For instance, the weight of heavy equipment on soils can compact the soil and thereby change it in some ways, such as in its ability to absorb water. Compacted soil is a major problem, taking thousands of acres permanently out of wildlife habitat. Trees will not grow in compacted soil.
Special use permit
A permit issued to an individual or group by the USDA Forest Service for use of National Forest land for a special purpose.
Stand
A group of trees that occupies a specific area and is similar in species, age, and condition.
Standards and guidelines
Requirements found in a Forest Plan which impose limits on natural resource management activities, generally for environmental protection.
Successional stage
A stage of development of a plant community as it moves from bare ground to climax. The grass-forb stage of succession precedes the woody shrub stage.
Succession
The natural replacement, in time, of one plant community with another. Conditions of the prior plant community (or successional stage) create conditions that are favorable for the establishment of the next stage.
Sustainability
The ability of an ecosystem to maintain ecological processes and functions, biological diversity, and productivity over time.
Sustainable
The yield of a natural resource that can be produced continually from generation to generation, without depleting the resource.
Sustained yield
Term used in the O&C Act of 1937. The yield that can be produced continuously by converting all the land to a tree plantation and logged rotationally.
Thinning
A cutting made in an immature stand of trees to accelerate growth of the remaining trees or to improve the form of the remaining trees. Thinning is often used to enhance old growth characteristics.
Threatened species
Those plant or animal species likely to become endangered throughout all or a specific portion of their range within the foreseeable future, sometimes designated by the U.S. Fish and Wildlife Service under the Endangered Species Act of 1973.
Tractor logging
A logging method that uses tractors to carry or drag logs from the stump to a collection point. This method produces the highest and longest ranging negative environmental impacts.
Underburn
A burn by a surface fire that can consume ground vegetation and "ladder" fuels.
Understory
The trees and woody shrubs growing beneath the overstory in a stand of trees.
Uneven-aged management
Actions that maintain a forest or stand of trees composed of intermingling trees that differ markedly in age. Cutting methods that develop and maintain uneven-aged stands are single-tree selection and group selection.
Watershed
The entire region drained by a waterway or into a lake or reservoir. More specifically, a watershed is an area of land above a given point on a stream that contributes water to the streamflow at that point.
Wetlands
Areas that are permanently wet or are intermittently covered with water.
Wilderness Area
Undeveloped federal land retaining its primeval character, without permanent human habitation or improvements. It is protected and managed to preserve its natural condition. Wilderness Areas are designated by Congress. 
Wildland Fire
Any non-structure fire, other than prescribed fire, that occurs in the wildland.
Wildland urban interface (WUI)
Areas where communities are expanding into tracitional forest and other resource lands.
Yarding
Moving the cut trees from where they were felled to a centralized place (landing) for hauling away from the stand.
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