Advanced Very High Resolution Radiometer (AVHRR) – A broad-band, four or five channel scanner, sensing in the visible, near-infrared, and thermal infrared portions of the electromagnetic spectrum at a spatial resolution of 1.1km. The AVHRR data record extends from 1978 to present.
Basal Area – The cross-sectional area of a tree stem, including the bark, measured at breast height (4.5 feet above the ground).
Basal Area Loss – In the context of Rapid Assessment of Vegetation Condition after Wildfire analysis, the percent change in basal area relative to the pre-fire condition. Basal area loss does not describe a permanent loss of basal area within a forest, but simply describes the amount of change in live basal area at the time of assessment. Also called basal area mortality or percent change in basal area.
Burn Severity – A qualitative assessment of the heat pulse directed toward the ground during a fire. Burn severity relates to soil heating, large fuel and duff consumption, consumption of the litter and organic layer beneath trees and isolated shrubs, and mortality of buried plant parts.
Burned Area Boundary – The boundary defining the area burned by a fire. In the context of satellite-based post-fire burn severity mapping, burned areas are typically delineated using remote sensing indices and/or spectral data, and may include unburned “island” areas.
Burned Area Emergency Response (BAER) – A program in the Forest Service and Department of Interior designed to determine the need for and to prescribe and implement emergency treatments on Federal Lands to minimize threats to life or property resulting from the effects of a fire or to stabilize and prevent unacceptable degradation to natural and cultural resources.
Burned Area Emergency Response (BAER) Team – BAER teams are formed to analyze post-fire conditions and to take immediate emergency stabilization action to prevent loss of life and property and critical and natural resources. It is the Agency Administrator’s responsibility to order or designate a BAER Team.
Burned Area Reflectance Classification (BARC) – A satellite-derived data layer of post-fire vegetation condition. The BARC has four thematic classes representing burn severity: high, moderate, low, and unburned. This product is used as an input to the soil burn severity data/map product produced by the Burned Area Emergency Response teams.
Canopy Cover – The ground area covered by the crowns of trees or woody vegetation as delineated by the vertical projection of crown perimeters. It is commonly expressed as a percent of total ground area. Also called crown cover. (Society of American Foresters. The Dictionary of Forestry, John A. Helms, Editor, 1998).
Canopy Cover Loss – In the context of Rapid Assessment of Vegetation Condition after Wildfire analysis, the percent change in live canopy cover relative to the pre-fire condition. Depending on the vegetation type and fire characteristics, the canopy cover loss estimate for an extended assessment may differ significantly from that of an initial assessment. Also called canopy cover mortality or percent change in canopy cover.
Char – Visual estimate of soil or vegetation burn that is essentially the percent of the surface that has been scorched (blackened).
Closed Tree Canopy – Vegetation dominated by trees with interlocking crowns, typically at least 60% crown cover.
Composite Burn Index (CBI) –A numerical, synoptic rating calculated from a field-based estimate of fire effects on individual strata within a plot or site in a burned area (Composite Burn Index | Burn Severity Portal). Estimates the overall impact to a site based on post-fire conditions averaged across the burnable portion of the site
Conterminous United States (CONUS) – The 48 states an the District of Columbia wholly filling an unbroken block of territory and excluding Alaska and Hawaii.
Contained/Containment – The status of a wildfire suppression action signifying that a control line has been completed around the fire, and any associated spot fires, which can reasonably be expected to stop the fire's spread.
Deforested Vegetation Condition – A temporary condition of the forest vegetation after a wildfire has burned at such high severity that not enough trees were left alive for the forest to naturally regenerate and function normally. It is a signal that reforestation treatments are required to re-establish forest cover promptly. As a rule, this describes a resulting forest with less than 20% canopy cover. A follow-up diagnosis followed by a silvicultural prescription is required to complete the final assessment and determine the type of management activities that are needed to recover the area.
Differenced Normalized Burn Ratio (dNBR) – A differenced NBR image, or change image, created where the post-fire NBR is subtracted from the pre-fire NBR (Landscape Assessment (LA) | US Forest Service Research and Development). The dNBR may be used to discriminate burned from unburned areas and identify vegetation burn severity classes. The dNBR is calculated as:
dNBR = NBR pre-fire – NBR post-fire
6 Class Thematic Burn Severity Classification (derived from dNBR) (dNBR6) – A continuous dNBR image thresholded to yield thematic burn severity classes, including unburned to low, low, moderate, high, increased greenness and non-processing mask/area.
Differenced Normalized Difference Vegetation Index (dNDVI) –A differenced NDVI image, or change image, created where the post-fire NDVI is subtracted from the pre-fire NDVI (Hudak et al 2007). The dNDVI may be used like the dNBR to discriminate burned from unburned areas and identify vegetation burn severity classes. The dNDVI is calculated as:
dNDVI = NDVI pre-fire – NDVI post-fire
Emergency Assessment – Fire mapping assessments that rely on satellite data typically required at or near fire containment in order to assist in identifying imminent post-fire threats to life, safety, property, and critical natural and cultural resources, and support emergency stabilization measures before significant storms occur.
Emergency Stabilization – Planned actions to stabilize and prevent unacceptable degradation to natural and cultural resource, to minimize threats to life or property resulting from the effects of a fire, or to repair/replace/construct physical improvements necessary to prevent degradation of land or resources.
Environmental Systems Research Institute – A geographic information system (GIS) mapping software, location intelligence & spatial analytics technology company.
European Space Agency (ESA) – An intergovernmental organization, consisting of 22 countries and created in 1975, with the mission to shape the development of Europe's space capability and ensure that investment in space delivers benefits to the citizens of Europe and the world.
Event Mapping Tool (EMT) – A graphical user interface developed by the Forest Service/USGS that uses scripts and commercial and open-source data processing tools to ensure consistent data processing and generation of post-fire mapping products by analysts.
Extended Assessment – Fire mapping assessments that rely on satellite data typically acquired during the growing season following a fire in order to include delayed first order effects (e.g., latent tree mortality) and dominant second order effects that are ecologically significant (e.g., initial site response and early secondary effects).
Extensible Markup Language (XML) – A software- and hardware-independent language based on Standard Generalized Markup Language (SGML) for storing and transmitting data, including geospatial metadata.
Federal Geographic Data Committee (FGDC) – An interagency committee of Federal geospatial professionals and constituents that provide executive, managerial, and advisory direction and oversight for geospatial decisions and initiatives across the Federal government.
Fire Atlas – A compendium of geospatial layers, maps, and tabular information that illustrate fire activity at the individual fire level for a given geographic area and/or period of time.
Fire Effects – The physical, biological, and ecological impacts of fire on the Environment.
Fire Effects Monitoring and Inventory System (FIREMON) – An agency independent plot level sampling system designed to characterize changes in ecosystem attributes over time.
Fire Intensity – The amount of energy or heat release per unit time or area during the consumption of organic matter.
Fire Mapping Tool (FMT) – In the context of QGIS, a graphical user interface developed by the USGS that uses scripts and QGIS data processing tools to allow any user to consistently process data and generate post-fire mapping products according to MTBS protocol.
Fire Severity – Degree to which a site has been altered or disrupted by fire; loosely, a product of fire intensity and residence time.
First Order Fire Effects – The effects that concern the direct or immediate consequences of fire, such as biomass consumption, crown scorch, bole damage, and smoke production. First order effects form an important basis for predicting secondary effects such as tree regeneration, plant succession, and changes in site productivity, but these involve interaction with many other non-fire variables.
Forested Vegetation Condition – A post-fire condition in which fire severity was classified as low, with the initial assessment showing enough live trees remaining for the forest to function normally. Most of the area has more than 20% canopy cover. A follow-up diagnosis and silvicultural prescription may be required to complete the final assessment and determine what type of management activities are needed to maintain the growth and vigor of the forest. Also, a severity class used in Rapid Assessment of Vegetation Condition after Wildfire assessments in 2007, in which percent basal area loss is less than 50%.
Geographic Information System (GIS) – A computer system that analyzes and displays geographically referenced information.
Government Accountability Office (GAO) – An independent, non-partisan agency within the legislative branch that investigates federal spending and performance. It supports the Congress in meeting its constitutional responsibilities and helps improve the performance and accountability of the federal government for the benefit of the American people.
Google Earth Engine (GEE) – A cloud-based geospatial analysis platform that enables users to visualize and analyze airborne and satellite imagery of Earth.
Ground Cover – Organic cover including litter, duff, and woody debris that can mitigate runoff and erosion.
Healthy Forests Restoration Act (HFRA) – A wildland fire management initiative initiated in August 2002 to reduce the risks severe wildfires pose to people, communities, and the environment.
High Burn Severity – A discrete burn severity class identified when thresholding dNBR data for Burned Area Emergency Response or Monitoring Trends in Burn Severity assessments, dNDVI for BAER assessments or RdNBR data for Rapid Assessment of Vegetation Condition after Wildfire assessments. In forested ecosystems, it typically represents areas affected by fire where:
- Substrates, litter is totally consumed; duff is typically nearly entirely consumed;
- Medium and heavy woody debris are at least partially consumed and at least deeply charred with mostly ash and charcoal remaining;
- Overstory trees typically exhibit greater than 75 percent mortality;
- Crown char is typically 100 percent from torching fire, and significant branch loss is present at the highest crown levels.
In grassland and shrubland ecosystems, it typically represents areas affected by fire where:
- Over half of the site exhibits over 50 percent cover of newly exposed mineral soil or rock fragments;
- Herbaceous plants and shrubs are almost completely charred or consumed above ground, often with notable branch loss on taller shrubs;
- Resprouting from perennial plants, except grasses, is strongly reduced.
Hydrophobicity – Resistance to wetting exhibited by some soils, also called water repellency. The phenomenon may occur naturally or may be fire-induced. It may be determined by water drop penetration time, equilibrium liquid-contact angles, solid-air surface tension indices, or the characterization of dynamic wetting angles during infiltration.
Increased Greenness – A discrete burn severity class identified when thresholding dNBR data for Monitoring Trends in Burn Severity assessments. It typically represents areas that burned but display more vegetation cover, density, and/or productivity, usually within one growing season after fire. This is a fire-caused effect from release of nutrients into soil, and/or reduced competition for nutrients, light and water. These areas are usually herbaceous or low shrub communities that undergo little change in species composition after fire.
Initial Assessment – Fire mapping assessments that rely on satellite data typically acquired at the first opportunity after fire to capitalize on the maximum post-fire data signal and is used primarily in ecosystems that exhibit rapid post-fire vegetation response (i.e. herbaceous and particular shrubland systems).
Integrated Reporting of Wildland Fire Information (IRWIN)– a service that exchanges and integrates fire reporting information from several systems of record. It provides a central repository for basic fire information to reduce redundant data entry and improve the consistency of information.
Keyhole Markup Language (KML) – A file format used to display geographic data in an Earth browser such as Google Earth.
Keyhole Markup Language(Compressed) (KMZ) – A KML file with geographic data and zero or more supporting files that are packaged using a Zip utility into an archive that can be displayed in an Earth browser such as Google Earth.
Landsat Imagery – Thematic Mapper, Enhanced Thematic Mapper Plus, and Operational Land Imager image data from the Landsat 5, Landsat 7, and Landsat 8 satellites, respectively. Image scenes have a footprint area of approximately 34,000 square kilometers and a pixel resolution of 30 meters. Spectral information is contained in several bands representing distinct wavelengths in the visible, infrared, and thermal portions of the electromagnetic spectrum.
Landscape Fire and Resource Management Planning (LANDFIRE) – A mapping program with products designed to support strategic vegetation, fire, and fuels management planning across multiple boundaries. The available geospatial products describe potential and existing vegetation, surface and canopy fuel characteristics, and simulated historical fire regimes conditions.
Low Burn Severity – A discrete burn severity class identified when thresholding dNBR data for Burned Area Emergency Response or Monitoring Trends in Burn Severity assessments, dNDVI for Burned Area Emergency Response assessments or RdNBR data for Rapid Assessment of Vegetation Condition after Wildfire assessments. It includes areas where more than a small proportion of the site burned. All vegetation strata are slightly altered from the pre-fire state, but some may show pronounced burn effects. In forested ecosystems, it typically represents areas affected by fire where:
- Substrates, litter often exhibits fairly high consumption (up to 100 percent).
- Duff, woody debris and newly exposed mineral soil typically exhibit some change.
- Low vegetation (<1 meter) and shrubs or trees (1-5 meters) may show significant aboveground scorch, char or consumption, and vegetation density or cover may be greatly altered.
- Intermediate and large overstory trees may exhibit up to 25 percent mortality evidenced by crown char or scorch.
- Char height from ground flames is typically less than 3 meters.
Moderate Burn Severity – A discrete burn severity class identified when thresholding dNBR data for Burned Area Emergency Response or Monitoring Trends in Burn Severity (MTBS) assessments, dNDVI for Burned Area Emergency Response assessments or RdNBR data for Rapid Assessment of Vegetation Condition after Wildfire assessments. It includes areas that exhibit conditions that are transitional in magnitude and/or uniformity between characteristics within low and high burn severity classes.
Moderate Resolution Imaging Spectroradiometer (MODIS) – A moderate resolution radiometer sensing in the he visible, near-infrared, shortwave infrared and thermal infrared portions of the electromagnetic spectrum. Spatial resolution is band dependent with 29 bands collected at a spatial resolution of 1km, five bands at 500 meters and two bands collected at 250 meters. The MODIS data record extends from late 1999 to present.
Monitoring Trends in Burn Severity (MTBS) – A program in 2005 and conducted jointly by the Forest Service and Department of Interior to map the location, extent and associated burn severity of all large fires in the United States. The program generates a suite of geospatial data for targeted fires occuring across all ownerships from 1984 to presentand are intended to meet numerous policy, operational and research needs.
MTBS Data Explorer (MDE) – A web-based application that leverages Google Earth Engine to visualize and analyze MTBS data.
Multispectral Instrument (MSI) – A multispectral imager of the Sentinel-2 program sensing in the visible, near-infrared and shortwave infrared portions of the electromagnetic spectrum and used for monitoring Earth's resources. Spatial resolution is band dependent with three bands collected at 60 meters, six bands collected at 20 meters and four bands collected at 10 meters.
Fire Occurrence Database – Relevant spatial and aspatial fire occurrence data elements for each fire mapped and assessed.
National Aeronautics and Space Administration (NASA) – A federal agency created in 1958 that is responsible for science and technolgy related to air and space.
National Fire Plan (NFP) – A wildland fire management initiative developed in August 2000 to respond to severe wildland fires and their impacts to communities while ensuring sufficient firefighting capacity for the future.
National Fire Plan Operations and Reporting System (NFPORS) – An interagency system funded by the Department of Interior and and Department of Agriculture for planning, managing, reporting and tracking of hazardous fuels, post-fire recovery and community assistance activities. The system enables uniform reporting of wildand fire information at field, regional and national levels.
National Forest – A unit formally established and permanently set aside and reserved for National Forest purposes. There are 154 National Forests in the United States, located in 43 states and Puerto Rico.
National Forest System - A nationally significant system of Federally owned units of forest, range, and related land consisting of national forests, purchase units, national grasslands, land utilization project areas, experimental forest areas, experimental range areas, designated experimental areas, other land areas, water areas, and interests in lands that are administered by the U.S. Forest Service or designated for administration through the Forest Service. Also see Section 11 of Forest and Rangeland Renewable Resources Planning Act of 1974 (P.L. 93-378, 88 Stat. 476, 16 U.S.C. 1609).
National Land Cover Database (NLCD) – A Landsat-based, 30-meter resolution land cover database for the United States. The database provides spatial reference and descriptive data for land cover type, percent impervious surface and percent tree canopy cover.
Non-Processing Mask – A discrete class assigned in Burned Area Emergency Response, Rapid Assessment of Vegetation Condition after Wildfire and Monitoring Trends in Burn Severity assessments representing areas of the fire masked out from the analysis. It includes pixels/areas where a reliable burn severity assessment cannot be conducted due to one or more satellite data or atmospheric/terrain interference issues (e.g. data gaps in Landsat 7 Scan Line Corrector-off imagery, clouds, cloud shadows, active fire, smoke, snow, and open water).
Normalized Burn Ratio (NBR) – A normalized index that leverages the contrast in response by the near-infrared (NIR) and short-wave infrared (SWIR) bands to leaf area, plant productivity and moisture (Landscape Assessment (LA) | US Forest Service Research and Development). Healthy, green vegetation has a high reflection of NIR light and strongly absorbs SWIR light resulting in high NBR values. Increasing damage to vegetation by fire and the exposure of dry, rocky soils results in low NBR values. NBR is calculated for each pre-fire and post-fire scene as:
NBR = (NIR - SWIR) ÷ (NIR + SWIR)
6 Class Thematic Burn Severity Classification (derived from NBR) (NBR6) – A continuous NBR image thresholded to yield thematic burn severity classes, including unburned to low, low, moderate, high, increased greenness and non-processing mask/area.
Normalized Difference Vegetation Index (NDVI) – A normalized index that emphasizes the contrast in response by the red (R) and near-infrared (NIR) bands to chlorophyl and the cell structure of vegetation (Hudak et al 2007). The chlorophyl in healthy, green vegetation absorbs visible (R) light while the cell structure of the healthy vegetation reflects NIR light resulting in high NDVI values. Increasing damage to vegetation by fire and/or seasonal vegetation senescence results in low NDVI values. NDVI is calculated for each pre-fire and post-fire scene as:
NDVI = (NIR - R) ÷ (NIR + R)
Open Geospatial Consortium (OGC) – A consortium committed to improving access to geospatial, or location information.
Open Tree Canopy – Vegetation dominated by trees with crowns not usually touching, typically with 25-60% crown cover.
Operational Land Imager (OLI) – A fourth generation multispectral imager of the Landsat program sensing in the visible, near-infrared, shortwave infrared and thermal infrared portions of the electromagnetic spectrum for monitoring Earth's resources. The spatial resolution is 30 meters for the eight optical bands, 15 meters for the panchromatic band and 100 meter spatial resolution for the two long wave thermal infrared bands. The Operational Land Imager data record spans from 2013 to present.
Portable Document Format (PDF) – A file format that provides an electronic image of text or text and graphics that looks like a printed document and can be viewed, printed, and electronically transmitted.
Prescribed Fire (Rx) – Any fire ignited by management actions to meet specific objectives.
Quantum Geographic Information System (QGIS) – A free, open-source and user friendly GIS application that supports data creation, editing, analysis and visualization of geospatial data.
Rapid Assessment of Vegetation Condition after Wildfire (RAVG) – A mapping program that provides a suite of standard geospatial products based on a rapid initial assessment of post-fire vegetation conditions following large wildfires on National Forests. The program methodology is also applied to provide the same products for selected wildfires on Department of Interior lands.
Reburn – An area that has reburned.
Relativized differenced Normalized Burn Ratio (RdNBR) – a normalized version of the dNBR that removes the biasing effect of the pre-fire conditions (Miller et al 2009). The RdNBR is calculated as:
RdNBR = dNBR / SquareRoot(ABS(NBR pre-fire / 1000))
Rehabilitation – Efforts undertaken within three years of a wildland fire to repair or improve fire damaged lands unlikely to recover to a management approved conditions or to repair or replace minor facilities damaged by fire.
Remote Sensing – the process of detecting and monitoring the physical characteristics of an area by measuring its reflected and emitted radiation at a distance (typically from satellite or aircraft) (US Geological Survey).
Scan Line Corrector (SLC) – A component of the Enhanced Thematic Mapper sensor which compensates for the forward motion of the satellite. This component failed on May 31, 2003 resulting in approximately 22% of data loss in each Landsat 7 scene and limiting its utility for mapping.
Sentinel 2 Imagery – Multispectral Instrument image data from the European Space Agency’s Sentinel 2A and Sentinel 2B satellites. Image scenes (tiles) have a footprint area of approximately 10,000 square kilometers and a pixel resolution of 10-20 meters. Spectral information is contained in several bands representing distinct wavelengths in the visible, infrared, and thermal portions of the electromagnetic spectrum.
Silvicultural Examination – The process of gathering field data for a forest stand to determine its current condition. Silvicultural and other management decisions are based on the data collected from these examinations. Rapid Assessment of Vegetation Condition after Wildfire data can be a useful tool for prioritizing field exams.
Silvicultural Prescription – A written document that describes management activities needed to implement treatments. It documents the results of an analysis of present and anticipated site conditions and management direction. It also describes desired future vegetation conditions in measurable terms. The desired conditions are a basis for treatment, monitoring, and evaluation.
Soil Burn Severity – The effect of a fire on ground surface characteristics, including char depth, organic matter loss, altered color and structure, and reduced infiltration.
Soil Burn Severity Data/Map – A dataset or map product that identifies fire-induced changes in soil and ground surface properties that may affect infiltration, runoff and erosion potential.
Soil heating – An increase in soil temperature as a result of heat transfer from the combustion of surface fuel and smoldering combustion of organic soil horizons.
Spatial Resolution – The areal extent of the smallest unit, pixel, or feature that can be resolved on an image, map, or surface. Typically expressed as a measure of distance, i.e., 30 meter pixel, but can also be expressed as a unit of area.
Spectral (Remote Sensing) Index – A mathematical calculation derived from two or more image bands. Typically used to enhance the spectral properties of a feature or condition of interest on the ground, i.e., burn scars.
Thematic Mapper (TM) – A second generation multispectral imager of the Landsat program sensing in the visible, near-infrared, shortwave infrared and thermal infrared portions of the electromagnetic spectrum for monitoring Earth's resources. The spatial resolution is 30 meters for the six optical bands and 120 meter spatial resolution for the single long wave thermal infrared band. The Thematic Mapper data record spans from 1982 to 2013.
Enhanced Thematic Mapper (ETM+) – A third generation multispectral imager of the Landsat program sensing in the visible, near-infrared, shortwave infrared and thermal infrared portions of the electromagnetic spectrum for monitoring Earth's resources. The spatial resolution is 30 meters for the six optical bands, 15 meters for the panchromatic band and 1=60 meter spatial resolution for the single long wave thermal infrared band. The Enhanced Thematic Mapper data record spans from 1999 to 2021.
Thematic Resolution – The finest level of content for a given map or thematic layer attribute.
Treatment – Any of a set of management activities that can assist in the prompt recovery of forestlands. Treatments can include any combination of live, dead, or dying wood removal or disposal (with or without commercial value) by logging, piling, masticating, burning, or other methods. In addition, planting or seeding, with or without site preparation, are appropriate management activities designed to foster prompt recovery following wildfire. In some cases, the preferred "treatment" is natural regeneration and monitoring.
Unburned to Low – A discrete burn severity class identified when thresholding dNBR data for Burned Area Emergency Response or Monitoring Trends in Burn Severity assessments or dNDVI for Burned Area Emergency Response assessments. It includes areas that are either unburned, or when visible fire effects occupy a small proportion of the site, on the order of less than 5 percent. The class may also include areas that recover very quickly after fire, such as grasslands or light surface burns under dense, non-impacted forest canopies.
Unmappable – A reported fire that is attempted to be mapped for a Burned Area Emergency Response, Rapid Assessment of Vegetation Condition after Wildfire or Monitoring Trends in Burn Severity assessment, but due to one or more technical issues, a publishable product cannot be generated.
United States Department of Agriculture (USDA) – An executive department of the United States federal government consisting of 29 agencies conducting farming, ranching and forestry management activities.
USDA Forest Service Geospatial Technology and Applications Center (GTAC) – A Federal science and technology center operated by the USDA Forest Service in Salt Lake City, Utah that provides burn severity mapping support for BAER, RAVG, MTBS, NPS and other relevant initiatives.
United States Geological Survey (USGS) – A federal agency in the Department of Interior created in 1879 and serves as the Nation's largest water, earth, and biological science and civilian mapping agency.
USGS Earth Resources Observation and Science Center (EROS) – A Federal science and technology center operated by the US Geological Survey in Sioux Falls, South Dakota that provides burn severity mapping support for BAER, RAVG, MTBS, NPS and other relevant initiatives.
Vegetation Group – In the context of Rapid Assessment of Vegetation Condition after Wildfire analysis, broad vegetation classes used for spatial analysis of burned area.
Vegetative regeneration – Development of new aboveground plants from surviving plant parts, such as by sprouting from a root crown or rhizomes. Even if plants form their own root system, they are still genetically the same as the parent plant.
Visible Infrared Imaging Radiometer Suite (VIIRS) – A moderate resolution radiometer sensing in the visible, near-infrared, shortwave infrared and thermal infrared portions of the electromagnetic spectrum. Spatial resolution is band dependent with 17 bands collected at a spatial resolution of 750 meters and five bands collected at 375 meters. The VIIRS data record extend from late 2011 to present.
Water repellent soils – A post-fire condition in some soils that are resistant to water penetration and not wettable.
Web Map Service (WMS) – A simple HTTP interface for requesting geo-registered map images from one or more distributed geospatial databases on the web for dynamic mapping.
Wilderness Area – Areas designated by Congress as a part of the National Wilderness Preservation System.
Wildfire – A wildland fire originating from an unplanned ignition, such as lightning, volcanos, unauthorized and accidental human caused fires, and prescribed fires that are declared wildfires.
Wildland Fire – Any non-structure fire that occurs in vegetation or natural fuels. Includes Wildfires and Prescribed Fires.
Wildland Fire Leadership Council (WFLC) – An intergovernmental committee formed by the Departments of Agriculture and Interior to support the implementation and coordination of Federal Fire Management Policy.
Wildland Fire Use (WFU) (Obsolete) – The application of the appropriate management response to naturally-ignited wildland fires to accomplish specific resource management objectives in predefined designated areas outlined in Fire Management Plans. Also called Wildfire for Resource Benefit.
Terms and definitions used in this glossary are derived from multiple sources, including the NWCG Glossary of Wildland Fire Terminology, Field Guide for Mapping Post-Fire Soil Burn Severity, FIREMON: Fire effects monitoring and inventory system, and Department of Interior/USDA Forest Service post-fire mapping and assessment programs (BAER Imagery Support, Rapid Assessment of Vegetation Condition after Wildfire and Monitoring Trends in Burn Severity).