Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
Congressional research reportMay 8, 2026
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Hazardous Fuels and Wildfire Mitigation:
Background and Congressional
Considerations
Updated May 8, 2026
Congressional Research Service
https://crsreports.congress.gov
R48779
SUMMARY
Hazardous Fuels and Wildfire Mitigation:
Background and Congressional Considerations
Hazardous fuels are combustible vegetation that accumulates on the landscape, presenting a
latent threat of starting and spreading wildfires that resist control. Land managers mitigate
hazardous fuels for various reasons, including protecting human life and property; protecting
desired uses or resources threatened by fire, known as values at risk; and promoting overall
ecosystem health. Fire practitioners use specific terms and concepts, some of which are
standardized, to discuss hazardous fuels.
R48779
May 8, 2026
Alicyn R. Gitlin
Analyst in Natural
Resources Policy
Fire has performed a functional role across much of North America, determining vegetation structure and composition on
forested and non-forested land. A composite of fire properties typical of a place is described as a fire regime; some attributes
of fire regimes are standardized in scientific and policy documents or statute.
Fuel treatments are the means by which land managers alter hazardous fuels to influence potential fire behavior. The most
prevalent approaches for reducing fuels are burning and mechanical treatments (involving tools or machinery). Other
approaches include chemical (herbicide) and biological (i.e., grazing, insect) controls. Each approach has benefits and
drawbacks.
Hazardous fuels and their associated wildfire threats cross land management and ownership boundaries. Five federal agencies
across two departments manage hazardous fuels on federal and tribal lands: the Forest Service (FS), under the U.S.
Department of Agriculture, and the Bureau of Land Management (BLM), the National Park Service (NPS), the Fish and
Wildlife Service (FWS), and the Bureau of Indian Affairs (BIA), under the Department of the Interior.
Congress has, at times, provided specific authorities related to hazardous fuels management on federal lands. Prominent
among these is the Healthy Forests Restoration Act (HFRA; 16 U.S.C. §§6501 et seq.), which pertains to the National Forest
System, managed by the FS, and to the public lands managed by BLM. HFRA includes provisions related to planning,
implementation, and administrative processes for specified projects, including hazardous fuel treatments. Congress also has
enacted authorities to facilitate collaborative hazardous fuels mitigation across land ownerships. The federal government also
helps nonfederal groups address hazardous fuels on nonfederal lands, generally by providing financial or technical assistance.
Congress regularly considers legislation related to hazardous fuels management on federal and nonfederal lands. Bills
introduced in the 119th Congress would affect the planning, implementation, and oversight of fuels mitigation projects, as
well as the workforce responsible for fuels management. Questions that Congress may consider regarding whether and how
to address hazardous fuels include the following:
•
•
•
Do existing authorities and programs adequately address hazardous fuels mitigation?
What issues impact the pace and scale of project implementation?
How do agencies track progress in a consistent manner that enables oversight while incentivizing effective
fuel treatments where they are needed most?
Congressional Research Service
Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
Contents
Overview ......................................................................................................................................... 1
Concepts and Terminology .............................................................................................................. 1
Hazardous Fuels and Fire Behavior ................................................................................................ 3
Fire Regimes: Fire over Time and Space .................................................................................. 6
Fire on Non-Forested Lands...................................................................................................... 7
Fuels Mitigation Approaches ........................................................................................................... 8
Fire as a Fuels Mitigation Approach ......................................................................................... 8
Prescribed Fires and Use of Wildland Fire ......................................................................... 8
Cultural Burning ............................................................................................................... 10
Benefits and Risks of Use of Wildland Fire ....................................................................... 11
Mechanical Treatments ........................................................................................................... 13
Advantages and Disadvantages of Mechanical Treatments .............................................. 14
Biological and Chemical Approaches ..................................................................................... 15
Targeted Grazing ............................................................................................................... 15
Herbicide Application ....................................................................................................... 18
Fuel Breaks and Firebreaks ..................................................................................................... 19
Maintenance ............................................................................................................................ 21
Federal Role and National Policies ............................................................................................... 21
Federal Role in Hazardous Fuels Mitigation........................................................................... 21
The Healthy Forests Restoration Act ................................................................................ 22
Collaboration with Nonfederal Groups ............................................................................. 23
Federal Support for Hazardous Fuels Management on Nonfederal Lands ....................... 23
Issues for Congress ........................................................................................................................ 24
Authorizations and Programs .................................................................................................. 24
Pace and Scale of Implementation .......................................................................................... 24
Tracking and Accountability ................................................................................................... 25
Tables
Table 1. Elements of Hazardous Fuels ............................................................................................ 2
Table A-1. Fire Regime Classifications ......................................................................................... 28
Table A-2. Fire Regime Condition Class ....................................................................................... 29
Table B-1. Hazardous Fuels Mitigation Bills in the 119th Congress.............................................. 31
Appendixes
Appendix A. Fire Regime Classifications ..................................................................................... 28
Appendix B. Hazardous Fuels Mitigation Introduced Legislation in the 119th Congress ............. 31
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Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
Contacts
Author Information........................................................................................................................ 35
Congressional Research Service
Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
Overview
Congressional debates regarding hazardous fuels surround whether and how to manage hazardous
fuels to promote resilient landscapes and community protection, as well as how to plan, report on,
and measure the success of fuels mitigation projects. The 108th Congress passed legislation, the
Healthy Forests Restoration Act (HFRA), to address “planning, prioritizing, and implementing
hazardous fuel reduction projects.”1 Congress also faces decisions about the federal government’s
role in assisting nonfederal land owners with fuels mitigation projects.
Hazardous fuels are combustible vegetation that accumulates on the landscape, presenting a threat
of starting and spreading wildfires that resist control. Hazardous fuels and their associated
wildfire threats cross land management and ownership boundaries. Five wildland fire
management agencies (WFMAs) across two departments are responsible for the majority of
hazardous fuels mitigation on federal and tribal lands—the Forest Service (FS), under the U.S.
Department of Agriculture (USDA), and the Bureau of Land Management (BLM), the National
Park Service (NPS), the Fish and Wildlife Service (FWS), and the Bureau of Indian Affairs
(BIA), under the Department of the Interior. The federal government also provides assistance to
nonfederal groups to address hazardous fuels on nonfederal lands.
Federal and nonfederal land managers mitigate hazardous fuels (often called hazardous fuel
reduction or fuel treatments) for various reasons. These reasons include altering fire behavior;
protecting human life and property; protecting other desired uses or resources threatened by fire,
known as values at risk; and promoting overall ecosystem health. Much of the debate surrounding
hazardous fuels and wildfire mitigation focuses on how to protect life and property in the
wildland-urban interface (WUI), where human development abuts undeveloped wildlands.
Fuel treatments are the means by which land managers alter hazardous fuels to influence
potential fire behavior. The most prevalent approaches for reducing fuels are burning and
mechanical treatments (involving tools or machinery). Other approaches include chemical
(herbicide) and biological (e.g., grazing, insect) controls. Land managers choose mitigation
approaches on the basis of various factors, such as cost, terrain, human safety, wildlife occupancy,
public opinion, workforce, and local industries.
This report begins with an explanation of hazardous fuels mitigation terminology, concepts, and
practice. Then it provides background on the role of the federal government and the principal
laws and policies affecting the management of hazardous fuels on federal and nonfederal lands.
The report concludes by discussing some issues Congress may consider that concern hazardous
fuels mitigation. Finally, appendices discuss fire regime classifications and legislation introduced
in the 119th Congress that could affect hazardous fuels mitigation policy or implementation.
Concepts and Terminology
Although the terms fuels and hazardous fuels are widely used in scientific, policy, and advocacy
contexts, they and other synonymous terms have no formal, standardized definition.2 For the
1 Healthy Forests Restoration Act (HFRA; 16 U.S.C. §§6501 et seq.).
2 Phrases such as hazardous fuels, biomass fuels, and vegetative fuels generally are interchangeable. In statute,
hazardous fuels is commonly used. The term biomass is often applied when there is a potential economic value for
combustible materials extracted from the landscape. For examples of uses of hazardous fuels in various contexts, see
16 U.S.C. §§6511 et seq., 16 U.S.C. §6704, and 43 U.S.C. §1748b, and of uses of biomass in various contexts, see 16
U.S.C. §7303, 16 U.S.C. §6592b, and 7 U.S.C. §8113. For an analysis of biomass definitions, see CRS Report R40529,
Biomass: Comparison of Definitions in Legislation, by Kelsi Bracmort.
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Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
purposes of this report, fuels are defined as combustible vegetative material.3 Hazardous fuels are
defined as “a fuel complex defined by kind, arrangement, volume, condition, and location that
presents a threat of ignition and resistance to control.”4 A fuel complex is an assemblage of fuels.5
Each of the elements (fuel kind, fuel arrangement, fuel volume, and fuel condition) has a
commonly understood definition (see Table 1).
No single statutory definition of hazardous fuels applies to all public lands.6 Similarly, no broadly
applicable definition appears in statute for hazardous fuel reduction projects. Existing definitions
pertain to specific areas of federal land or other specific circumstances. In particular, statute
defines certain activities on federal lands as “authorized hazardous fuel reduction project[s]” for
the purpose of HFRA.7 The definition generally does not apply beyond the specified areas and
parameters defined in HFRA, discussed in the “The Healthy Forests Restoration Act” section of
this report.
Table 1. Elements of Hazardous Fuels
Term
Fuel Kind or Fuel
Type
Definition
“An identifiable association of fuel elements of distinctive species, form, size,
arrangement, or other characteristics that will cause a predictable rate of spread or
resistance to control under specified weather conditions.”
Fuel types include grass, grass/shrub, shrub, timber understory, timber litter, and
slash/blowdown (debris from natural or human-caused events such as wind or logging).a
Some additional fuel characteristics include the following:
•
Heavy fuels: “Fuels of large diameter such as snags, logs, large limbwood, which
ignite and are consumed more slowly than flash fuels.”
•
Light (fine) fuels: “Fast-drying fuels, generally with a comparatively high surface areato-volume ratio, which are less than 1/4-inch in diameter.... These fuels readily
ignite and are rapidly consumed by fire when dry.”
•
Flash fuels: “Highly combustible fine fuels such as grass, leaves, draped pine needles,
fern, tree moss and some kinds of slash, which ignite readily and are consumed
rapidly when dry.”
•
Live fuels: “Living plants, such as trees, grasses, and shrubs, in which the seasonal
moisture content cycle is controlled largely by internal physiological mechanisms,
rather than by external weather influences.”
•
Dead fuels: “Fuels with no living tissue in which moisture content is governed
almost entirely by absorption or evaporation of atmospheric moisture (relative
humidity and precipitation).”
3 Many other types of fuels exist, including oil, natural gas, and nuclear, and some could be considered hazardous. This
report does not address these other types of fuels.
4 See National Wildfire Coordinating Group (NWCG), Glossary of Wildland Fire, PMS 205, https://www.nwcg.gov/
publications/pms205/nwcg-glossary-of-wildland-fire-pms-205 (hereinafter NWCG Glossary). The NWCG is the
federal interagency coordinating and standard-setting group for wildland fire, and the NWCG Glossary contains
definitions for most terminology used by wildland fire management agencies in the U.S. Department of Agriculture
(USDA) and the Department of the Interior (DOI). Other agencies may repeat this definition in their policies and
guidance. For example, see Forest Service (FS), “Hazardous Fuels Management and Prescribed Fire,” in Forest Service
Manual 5140.
5 Mark J. Schroeder and Charles C. Buck, “Weather and Fuel Moisture,” in A Guide for Application of Meteorological
Information to Forest Fire Control Operations, PMS 425-1, NWCG, May 1970, https://www.nwcg.gov/publications/
pms425-1/11-weather-and-fuel-moisture (hereinafter NWCG, “Weather and Fuel Moisture”).
6 For examples of the use of hazardous fuel(s) in statute in various contexts, see 16 U.S.C. §§6511 et seq., 16 U.S.C.
§6704, and 43 U.S.C. §1748b. Hazardous fuels are defined in regulation for the Colorado and Idaho Roadless Areas
(36 C.F.R. §294.41 and 36 C.F.R. §294.21).
7 16 U.S.C. §6511(2), 16 U.S.C. §6512(a).
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Fuel Arrangement
“A general term referring to the spatial distribution and orientation of fuel particles or
pieces.”
•
Fuel continuity: “The degree or extent of continuous or uninterrupted distribution
of fuel particles in a fuel bed thus affecting a fire’s ability to sustain combustion and
spread.”
Fuel Loading or Fuel
Volume
“The amount of fuel present expressed quantitatively in terms of weight of fuel per unit
area. This may be available fuel (consumable fuel) or total fuel and is usually dry weight.”
Fuel Condition
“Relative flammability of fuel as determined by fuel type and environmental conditions.”
Source: Definitions from National Wildfire Coordinating Group, Glossary of Wildland Fire, PMS 205,
https://www.nwcg.gov/publications/pms205/nwcg-glossary-of-wildland-fire-pms-205.
a. Northwest Fire Science Consortium, “What Is Fuel?,” https://www.nwfirescience.org/sites/default/files/
publications/FIREFACTS_FUELS_0.pdf.
Hazardous Fuels and Fire Behavior
Three basic components necessary to start and sustain a fire are a heat source, oxygen, and fuel—
a concept known as the fire triangle. Wildland fire practitioners refer to a wildland fire behavior
triangle with three factors: weather, topography, and fuel.8 Land managers mitigate fuels to
influence fire behavior. Land managers and fire practitioners use specific terms and concepts to
talk about hazardous fuels and wildland fire behavior, which are defined in Table 1 and discussed
below.
Wildland firefighters classify fuel types to predict a fire’s heat output (fire intensity, sometimes
indicated as flame lengths) and rate of spread.9 Within each fuel type, fuel moisture, chemistry,
and density all determine flammability, with moisture being the most important factor.10 Dead
fuels dry more quickly than live fuels.11 The moisture content of live fuels varies seasonally,
whereas the moisture in dead fuels depends on recent and ongoing weather.12 Some species ignite
more readily and burn hotter than others.13 Fine, flash fuels—especially grasses—dry out quickly,
ignite easily, and spread fire rapidly.14 Large, heavy fuels with less surface area per volume take
longer to absorb moisture, and to lose moisture, than fine fuels.
8 National Park Service (NPS), “Wildland Fire Behavior,” February 16, 2017, https://perma.cc/6PRC-VJ7G.
9 Northwest Fire Science Consortium, “What Is Fuel?,” https://www.nwfirescience.org/sites/default/files/publications/
FIREFACTS_FUELS_0.pdf; NWCG, NWCG Guide to Fire Behavior Assessment, PMS 437-1, NFES 2636, December
2024, pp. 52-64, https://www.nwcg.gov/publications/pms437-1; Joe H. Scott and Robert E. Burgan, Standard Fire
Behavior Fuel Models: A Comprehensive Set for Use with Rothermel’s Surface Fire Spread Model, General Technical
Report RMRS-GTR-153, USDA, FS, Rocky Mountain Research Station (RMRS), June 2005, pp. 9-12,
https://training.nwcg.gov/dl/s290/s-290-usfs-standard-fire-behavior-fuel-models.pdf.
10 NPS, “Wildland Fire Behavior,” February 16, 2017, https://perma.cc/6PRC-VJ7G.
11 Ariel Cowan et al., Prescribed Fire Basics: Fuels, EM 9386, Oregon State University, April 2023,
https://extension.oregonstate.edu/sites/extd8/files/documents/12581/osu-rx-modules-fuels-em9386.pdf (hereinafter
Cowan et al., Prescribed Fire Fuels).
12 NWCG, “Weather and Fuel Moisture”; NPS, “Understanding Fire Danger,” April 15, 2025, https://www.nps.gov/
articles/understanding-fire-danger.htm.
13 Cowan et al., Prescribed Fire Fuels; Shusmita Saha and Jeanette Cobian-Iñiguez, “Effect of Fuel Structure and
Species on Grassy Fuel Ignition: Insights from Bench Scale Experiments and Thermogravimetric Analysis,” Fire and
Materials, vol. 49, no. 5 (August 2025), pp. 623-641; Brad Smith, Texas Wildland Fuel, Fuel Model Guide, Texas
A&M Forest Service, 2016 (hereinafter Texas A&M Forest Service, Texas Fuel Model Guide); NWCG, “Weather and
Fuel Moisture.”
14 John Rizza et al., Prescribed Fire Basics: Fire Behavior, Oregon State University Extension Service, EM9341,
(continued...)
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Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
Fuel arrangement, in particular fuel continuity (the extent that fuels are contiguous without gaps),
affects a fire’s ability to sustain combustion and spread.15 Fuel continuity can be vertical or
horizontal. Forest fuels are arranged on the ground (surface fuels), between the surface and the
treetops (ladder fuels), and in the canopy (crown fuels). Ladder fuels create vertical continuity
between the surface and crown fuels, lowering the amount of heat or wind required to bring fire
from the surface into the crown.16
Ladder fuels are critical to determining how fires that burn during extreme weather conditions
alter or disrupt forests (fire severity).17 When ladder fuels conduct fire into the crown of an
individual or small group of trees, it is called torching.18 During high winds, a low-intensity
surface fire can jump from the forest floor and move through the tree canopy, becoming a winddriven, high-intensity active crown fire that advances through both the canopy and the surface
fuels.19 Active crown fires sustain greater rates of spread in forests than surface fires.20 A
conflagration is a rapidly moving, destructive fire.21
Fuel type and fuel arrangement affect the interaction of fire and wind. For example, wind
generally spreads grassland fires faster than forest fires.22 This is partly because dense forests
slow the wind speed.23 Conflagrations are often spread by spotting, which occurs when burning
trees and twigs produce firebrands—flaming hot fuel particles carried by wind and convection
currents—that cause new ignitions ahead of the fire’s leading edge (fire front).24
February 2022, https://extension.oregonstate.edu/sites/extd8/files/documents/12581/osu-rx-modules-fire-behavior0423.pdf (hereinafter Rizza et al., Fire Behavior); Cowan et al., Prescribed Fire Fuels; Texas A&M Forest Service,
Texas Fuel Model Guide.
15 Stacy Drury, “Fuel Continuity,” in Encyclopedia of Wildfires and Wildland-Urban Interface (WUI) Fires, ed. Samuel
Manzello (Springer, 2019); NWCG Glossary.
16 Miguel G. Cruz and Martin E. Alexander, “The Start, Propagation, and Spread Rate of Crown Fire,” Fire
Management Today, vol. 73, no. 4 (2014), p. 19 (hereinafter Cruz and Alexander, “Start and Spread of Crown Fire”).
17 Cruz and Alexander, “Start and Spread of Crown Fire”; Christopher R. Hakkenberg et al., “Ladder Fuels Rather
Than Canopy Volumes Consistently Predict Wildfire Severity Even in Extreme Topographic-Weather Conditions,”
Communications Earth & Environment, vol. 5, no. 721 (November 20, 2024) (hereinafter Hakkenberg et al., “Ladder
Fuels”).
18 Cruz and Alexander, “Start and Spread of Crown Fire”; Hakkenberg et al., “Ladder Fuels.”
19 NWCG, “Active Crown Fire Behavior,” in Fire Behavior Field Reference Guide, PMS 437, April 1, 2025,
https://www.nwcg.gov/publications/pms437/crown-fire/active-crown-fire-behavior.
20 NWCG, “Weather: Estimating Winds for Fire Behavior,” in Fire Behavior Field Reference Guide, PMS 437, April 1,
2025, https://www.nwcg.gov/publications/pms437/weather/estimating-winds-for-fire-behavior; NWCG, “Fuels:
Canopy Fuel Characteristics,” in Fire Behavior Field Reference Guide, PMS 437, April 1, 2025, https://www-nwcgstg.fs2c.usda.gov/publications/pms437/fuels/canopy-fuel-characteristics; Wei-Ting Hung et al., “Evaluation of an InCanopy Wind and Wind Adjustment Factor Model for Wildfire Spread Applications Across Scales,” Journal of
Advances in Modeling Earth Systems, vol. 16, no. 7 (July 2024) (hereinafter Hung et al., “In-Canopy Wind”).
21
NWCG Glossary.
22 CSIRO, The 20% Wind Speed Rule of Thumb for Quickly Estimating a Grassfire's Forward Spread Rate, CSIRO
PyroPage Number 33, September 2022, https://research.csiro.au/pyropage/wp-content/uploads/sites/17/delightfuldownloads/2022/09/CSIRO-Pyropage-Issue-33-Grassfire-Rule-of-Thumb.pdf; Miguel G. Cruz and Martin E.
Alexander, “Uncertainty Associated with Model Predictions of Surface and Crown Fire Rates of Spread,”
Environmental Modelling & Software, vol. 47 (2013).
23 NWCG, “Weather: Estimating Winds for Fire Behavior,” in Fire Behavior Field Reference Guide, PMS 437, April 1,
2025, https://www.nwcg.gov/publications/pms437/weather/estimating-winds-for-fire-behavior; NWCG, “Fuels:
Canopy Fuel Characteristics,” in Fire Behavior Field Reference Guide, PMS 437, April 1, 2025, https://www-nwcgstg.fs2c.usda.gov/publications/pms437/fuels/canopy-fuel-characteristics; Hung et al., “In-Canopy Wind.”
24 Rizza et al., Fire Behavior; Samuel L. Manzello et al., “Role of Firebrand Combustion in Large Outdoor Fire
Spread,” Progress in Energy and Combustion Science, vol. 76 (January 2020); Samuel L. Manzello et al., “Firebrand
(continued...)
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Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
Fuel loading (or fuel load) is the total amount of fuel available to burn. Fuel loading influences
fire intensity and potential fire duration. Because the fuel loading consists of the entirety of fuels
that can be consumed in a fire, it determines the potential amount of smoke emissions.25 For these
reasons, an estimate of fuel loading is essential to safely working with fire.26
The fuel condition is the result of recent and ongoing weather interacting with the fuel complex.27
Several available indexes model fuel and weather conditions to estimate fire risk across large
areas and aid in decisionmaking.28
The location of fuels adds to the wildfire hazard and vulnerability those fuels present.29 Greater
vulnerability to fire exists when fuels are in proximity to values at risk—things people care about,
such as homes or sensitive wildlife habitats.30 Hazardous fuels might be within (intermix) or
adjacent to (interface) values at risk. Local factors such as topography, weather patterns, and
recreational usage will influence where fires are likely to ignite, how they will spread, and their
resistance to control.
Encroachment of human development on forest and grassland systems complicates wildfire
response and increases the number of lives and structures at risk.31 The area covered by the WUI,
where land developed by humans and undeveloped wildlands intermix or interface in the United
States, grew by one-third between 1990 and 2010.32 According to some researchers, human
activity and certain development patterns correlate with increasing wildfire ignitions.33 Much of
Generation from Burning Vegetation,” International Journal of Wildland Fire, vol. 16 (2007), pp. 458-462; Mohamad
El Houssami et al., “Experimental Procedures Characterising Firebrand Generation in Wildland Fires,” Fire
Technology, vol. 52 (2016), pp. 731-751; NPS, “Wildland Fire Behavior,” February 16, 2017, https://perma.cc/6PRCVJ7G.
25 Pamela G. Sikkink et al., Field Guide for Identifying Fuel Loading Models, USDA, FS, RMRS, RMRS-GTR-225,
May 2009, https://www.fs.usda.gov/rm/pubs/rmrs_gtr225.pdf (hereinafter Sikkink et al., Field Guide for Identifying
Fuel Loading Models); Northwest Fire Science Consortium, “What Is Fire Intensity?,” https://www.nwfirescience.org/
sites/default/files/publications/FIREFACTS_Intensity_0.pdf (hereinafter Northwest Fire Science Consortium, “What Is
Fire Intensity?”).
26 Northwest Fire Science Consortium, “What Is Fire Intensity?”; Cowan et al., Prescribed Fire Fuels; Sikkink et al.,
Field Guide for Identifying Fuel Loading Models.
27 NWCG, “Weather and Fuel Moisture.”
28 CRS In Focus IF12884, Fire Weather: Background and Forecasting, by Eva Lipiec; NPS, “Understanding Fire
Danger,” April 15, 2025, https://www.nps.gov/articles/understanding-fire-danger.htm; U.S. Geological Survey
(USGS), “Fire Danger Forecast,” accessed August 4, 2025, https://www.usgs.gov/fire-danger-forecast.
29 Sara Brown et al., Science You Can Use 101: Wildfire Risk, USDA, FS, RMRS, 2024, https://www.fs.usda.gov/
rm/pubs_journals/rmrs/sycu/2024/sycu101_2024_wildfire_risk.pdf (hereinafter Brown et al., Wildfire Risk).
30 Brown et al., Wildfire Risk.
31 James R. Karels and Monica Corbin, Wildland Urban Interface: A Look at Issues and Resolutions: A Report of
Recommendations for Elected Officials, Policymakers and All Levels of Government, Tribal and Response Agencies,
Federal Emergency Management Agency (FEMA), U.S. Fire Administration (USFA), June 2022,
https://www.usfa.fema.gov/downloads/pdf/publications/wui-issues-resolutions-report.pdf (hereinafter FEMA, USFA,
Wildland Urban Interface).
32 Between 1990 and 2010, the land area in the WUI grew by 33%, from 224,325 square miles to 297,298 square miles
(581,000 square kilometers to 770,000 square kilometers), and the number of new houses in the WUI grew by 41%
(30.8 million to 43.4 million). Volker C. Radeloff et al., “Rapid Growth of the U.S. Wildland-Urban Interface Raises
Wildfire Risk,” Proceedings of the National Academy of Sciences, USA, vol. 115, no. 13 (March 27, 2018), pp. 33143319; FEMA, USFA, Wildland Urban Interface.
33 Alexandra D. Syphard et al., “Human Influence on California Fire Regimes,” Ecological Applications, vol. 17, no. 5
(July 2007), pp. 1388-1402; Jennifer K. Balch et al., “Human-Started Wildfires Expand the Fire Niche Across the
United States,” Proceedings of the National Academy of Sciences, USA, vol. 114, no. 11 (March 14, 2017), pp. 29462951.
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Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
the debate surrounding hazardous fuels and wildfire mitigation centers on how to protect life and
property in the WUI.
Fuel treatments incorporate the means by which land managers alter hazardous fuels to influence
potential fire behavior—generally, to reduce the risk of ignitions, decrease fire intensity, and/or
reduce fire spread. To do so, fuel treatments might seek to rearrange or resize fuels, reduce fuel
loading, remove undesirable species, break up horizontal or vertical fuel continuity, or enact some
combination of these approaches, in accordance with their goals. Many hazardous fuel reduction
activities affect more than one element of fuels on the landscape and therefore may alter several
different aspects of fire behavior.
Fire Regimes: Fire over Time and Space
A fire regime is a composite of fire properties “typical” of a place, including the behavior of
individual fires (e.g., intensity, rate of spread) and the behavior of fire over time (e.g., frequency,
seasonality). Fire has performed a functional role across North America, determining vegetation
structure and composition in many ecosystems. Vegetation and wildlife that evolved with a
particular fire regime will tend to thrive in—and even depend on—that overall regime. Atypical
fire behavior (e.g., too frequent or too rare, too hot or not hot enough) might harm some species
or affect ecosystem functioning.34
Fire Regime Condition Class (FRCC) is a tool for describing fire’s historic role in an ecosystem
(historical fire regime) and how current vegetation conditions differ from a reference period prior
to Euro-American settlement (condition class).35 FRCC definitions are based on a 2002 FS
publication.36
The FS recognizes a total of five historical fire regimes that generally define natural fire
frequency and severity, as well as whether fire typically would burn mostly on the ground at low
temperature (low-severity), produce a mixture of effects on the landscape (mixed-severity), or
clear areas entirely for new growth (stand-replacement).37 The FS defines three condition classes,
forming a continuum based on departure from historical fire regime, changes in vegetation
attributes, and risk of losing key ecosystem components.38 Condition class one represents the
most similarity to the historical “norm” (i.e., prior to Euro-American settlement), whereas
condition class three is most dissimilar to the historic norm.
HFRA codified definitions for three fire regimes and two condition classes for purposes including
prioritizing, authorizing, and assessing hazardous fuel reduction projects under the act.39 (See
Table A-1 and Table A-2.) Specifically, HFRA provides certain tools for environmental
compliance and project expediting in areas with designated fire regimes, when they fall into
34 Luke T. Kelly and Lluís Brotons, “Using Fire to Promote Biodiversity,” Science, vol. 355, no. 6331 (March 24,
2017), pp. 1264-1265; Kendra K. McLauchlan et al., “Fire as a Fundamental Ecological Process: Research Advances
and Frontiers,” Journal of Ecology, vol. 108, no. 5 (September 2020), pp. 2047-2069 (hereinafter McLauchlan et al.,
“Fire as a Fundamental Process”); Thomas A. Spies et al., “Challenges and a Checklist for Biodiversity Conservation in
Fire-Prone Forests: Perspectives from the Pacific Northwest of USA and Southeastern Australia,” Biological
Conservation, vol. 145, no. 1 (January 2012), pp. 5-14.
35 Kirsten M. Schmidt et al., Development of Coarse-Scale Spatial Data for Wildland Fire and Fuel Management,
USDA, FS, RMRS, General Technical Report RMRS-GTR-87, April 2002, https://www.fs.usda.gov/rm/pubs/
rmrs_gtr087.pdf (hereinafter Schmidt et al., Coarse-Scale Spatial Data for Fuel Management).
36 Schmidt et al., Coarse-Scale Spatial Data for Fuel Management.
37 Schmidt et al., Coarse-Scale Spatial Data for Fuel Management.
38 Schmidt et al., Coarse-Scale Spatial Data for Fuel Management.
39 16 U.S.C. §6511(4-5); 16 U.S.C. §6511(8-10); 16 U.S.C. §6512.
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Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
designated condition classes.40 Table A-1 and Table A-2 provide the FS descriptions and statutory
definitions for fire regimes and condition classes.
FRCC is one way to describe landscape conditions. FRCC is principally relevant for HFRA
projects and projects that aim to restore patterns and processes to a historic range of variability or
historic range and variation (HRV). Debate exists over whether restoration to HRV is desirable in
places with significantly changed land uses, species compositions, or climatic conditions.41
Fire on Non-Forested Lands
Wildfire policy debates often focus on forests. However, several of the most destructive fires in
recent years began on non-forested lands. Grass and shrub fires in the United States burned 64%
of homes destroyed in wildfires between 1990 and 2020 (10,890 homes).42 The 2025 Los Angeles
County wildfires, the costliest wildfires in U.S. history, began in grass and shrub fuel types.43
Some features of grass and shrub fuel types create particular challenges. Low-elevation grasses
and shrubs grow rapidly in response to moisture fluctuations—far more rapidly than timber
fuels—meaning fuel loading in non-forested systems increases quickly after wet seasons. Fine
fuels dry out quickly, becoming flash fuels with higher risk of ignition than heavy fuels.44 The end
result is ecosystems where fire risk may change rapidly over short periods of time and where
conditions facilitate more frequent ignitions and rapid spread of fires.
Some invasive (i.e., nonnative) plants can change the fire regime, for example by increasing
horizontal fuel continuity or changing the ratio of dead to live fuels, enabling fires to quickly
spread.45 When dead biomass dries out adjacent to ignition sources—such as highways—or
values at risk—such as homes—the overall wildfire risk increases, sometimes leading to disaster
(as has occurred on the islands of Hawai’i).46
40 16 U.S.C. §6512.
41 Robert E. Keane et al., “The Use of Historical Range and Variability (HRV) in Landscape Management,” Forest
Ecology and Management, vol. 258 (2009), pp. 1025-1037; Robert E. Keane and Rachel A Loehman, “Historical
Range and Variation (HRV),” in Encyclopedia of Wildfires and Wildland-Urban Interface (WUI) Fires, ed. Samuel L.
Manzello (Springer, 2019).
42 Volker C. Radeloff et al., “Rising Wildfire Risk to Houses in the United States, Especially in Grasslands and
Shrublands,” Science, vol. 382, no. 6671 (November 10, 2023), pp. 702-707 (hereinafter Radeloff et al., “Rising
Wildfire Risk”).
43 Jean Eaglesham, “Los Angeles Fire Damage Likely to Be Costliest Blaze in U.S. History,” Wall Street Journal,
January 9, 2025; CRS In Focus IF12871, January 2025 Los Angeles County Wildfires, coordinated by Diane P. Horn
and Alicyn R. Gitlin.
44 Jon E. Keeley and Alexandra D. Syphard, “Different Fire-Climate Relationships on Forested and Non-Forested
Landscapes in the Sierra Nevada Ecoregion,” International Journal of Wildland Fire, vol. 24 (2015), pp. 27-36; Daniel
L. Swain et al., “Hydroclimate Volatility on a Warming Earth,” Nature Reviews Earth & Environment, vol. 6 (January
9, 2025), pp. 35-50; USDA, FS, RMRS, Fire Effects Information System (FEIS) “Fire Regimes of Plains Grassland and
Prairie Ecosystems,” accessed June 17, 2025, http://www.fs.usda.gov/database/feis/fire_regimes/PlainsGrass_
Prairie/all.html; Zhengpeng Li et al., “Assessment of Fire Fuel Load Dynamics in Shrubland Ecosystems in the
Western United States Using MODIS Products,” Remote Sensing, vol. 12, no. 12 (2020).
45 Martin C. Holdrege et al., “Wildfire Probability Estimated from Recent Climate and Fine Fuels Across the Big
Sagebrush Region,” Fire Ecology, vol. 20, no. 22 (February 28, 2024); Bethany A. Bradley et al., “Cheatgrass (Bromus
tectorum) Distribution in the Intermountain Western United States and Its Relationship to Fire Frequency, Seasonality,
and Ignitions,” Biological Invasions, vol. 20 (June 2018), pp. 1493-1506 (hereinafter Bradley et al., “Cheatgrass and
Fire”); CRS In Focus IF11011, Invasive Species: A Brief Overview, by Pervaze A. Sheikh.
46 Cost of Government Commission, County of Maui, Report on Wildfire Prevention and Cost Recovery on Maui, July
2021; CRS Insight IN12218, August 2023 Wildfires in Hawaii, coordinated by Linda R. Rowan.
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Fuels Mitigation Approaches
Land managers mitigate hazardous fuels for various reasons. Such reasons include protecting
human life and property, protecting other values at risk, promoting ecosystem health, and
achieving a combination of these aims. Land managers try to choose mitigation approaches, alone
or in combination, that best achieve their goals under prevailing ecological, legal, logistical, and
economic conditions. Various factors, such as cost, topography, human safety, wildlife occupancy,
public perception, workforce availability, and nearby local industries, might affect project design.
Managers also may choose project approaches that might generate co-benefits, such as choosing
land management techniques that benefit fire-dependent species, protect water quality, improve
wildlife habitat, or enhance other resources. The benefits and risks of various hazardous fuels
mitigation approaches are sometimes debated, and some groups have published
recommendations.47 Two of the most prevalent approaches for reducing fuels are burning and
mechanical treatments (or a combination of the two). Other approaches include chemical
(herbicide) and biological (e.g., grazing, insect) controls. Each approach has various benefits,
costs, risks, and limitations, as described below.
Fire as a Fuels Mitigation Approach
Prescribed Fires and Use of Wildland Fire
The use of fire to mitigate hazardous fuels and reduce the chances for future extreme or
uncharacteristic fire behavior is an established, widely used practice. Burning to achieve resource
benefits can occur as a prescribed fire, where the ignitions are planned, or as an unplanned
ignition (i.e., lightning) allowed to burn under supervision. For the purposes of this report, the
phrase use of wildland fire means applications of fire for resource benefits with either planned or
unplanned ignitions (see text box below entitled, “The Overlapping Terms That Define Wildland
Fire Response”). Land managers respond with fire suppression activities (efforts to extinguish a
fire) when fires present an unacceptable level of threat according to predetermined criteria or as
determined with the aid of a decision support system.48
47 The Wildland Fire Mitigation and Management Commission (hereinafter Wildland Fire Commission), authorized by
the Infrastructure Investment and Jobs Act (IIJA; P.L. 117-58, §§70201 et seq.), made several recommendations about
topics discussed in this report. See, for example, Wildland Fire Commission, On Fire: The Report of the Wildland Fire
Mitigation and Management Commission, September 2023, https://www.usda.gov/sites/default/files/documents/
wfmmc-final-report-09-2023.pdf (hereinafter Wildland Fire Commission, On Fire); relevant sections include “Enabling
Beneficial Fire,” “Use of Beneficial Fire,” “Enabling Indigenous Stewardship,” “Addressing Smoke Impacts,”
“Recruiting and Retaining the Workforce,” and “Tribal Equity.”
48 USDA and DOI, Guidance for Implementation of Federal Wildland Fire Management Policy, February 13, 2009.
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The Overlapping Terms That Define Wildland Fire Response
The terms that the federal wildland fire management agencies (WFMAs) and federal and nonfederal wildland
firefighters, scientists, and policy professionals use to define wildland fires can lead to confusion. Many federal and
nonfederal entities work together to plan for and respond to wildland fires. National offices such as the National
Wildfire Coordinating Group (NWCG) and National Interagency Fire Center set standards and provide
consistent information and terminology that is used by the WFMAs and the nonfederal entities that coordinate on
wildland fire response. For the purpose of managing wildland fires under federal jurisdiction, the WFMAs
distinguish between prescribed fire, meaning a planned ignition, and wildfire, meaning either an unplanned ignition or
an escaped prescribed fire (a prescribed fire that exceeded, or is expected to exceed, its intended area). The
WFMA definition of wildland fire includes both prescribed fires (within their prescribed parameters) and wildfires.
The NWCG’s Glossary of Wildland Fire defines the term use of wildland fire as “management of wildfire or
prescribed fire to meet resource objectives specified in land/resource management plans.”
The WFMAs manage all wildland fires under federal jurisdiction according to the same set of standardized
decisionmaking policies, aiming to minimize risks and impacts while adhering to relevant planning documents. The
federal decisionmaking framework allows wildland fires to be managed for one or more objectives that may
change as the fire spreads or conditions evolve. However, the WFMAs manage the use of wildland fire according
to the same overall decisionmaking framework, regardless of whether the ignition was planned or unplanned.
These overlapping definitions, where all wildfires are wildland fires and not all wildland fires involve use of wildland
fire, and where management decisions can change over time, may complicate communication about fire
management. These overlapping terms also may cause confusion about fire’s use in hazardous fuels reduction.
Although a prescribed fire is always a planned ignition, use of wildland fire or similar terms can denote either a
planned or an unplanned ignition source in scientific and policy documents.
Sources: U.S. Department of Agriculture (USDA) and Department of the Interior, Guidance for
Implementation of Federal Wildland Fire Management Policy, February 13, 2009, pp. 11, 14, 16-17, 18,
https://www.doi.gov/sites/doi.gov/files/uploads/2009-wfm-guidance-for-implementation.pdf; Interagency
Standards for Fire and Fire Aviation Operations Group, National Interagency Fire (NIFC), Interagency
Standards for Fire and Fire Aviation Operations ("Red Book”), January 2025, pp. 2-5, 148-159,
https://www.nifc.gov/standards/guides/red-book; NWCG, Glossary of Wildland Fire, PMS 205,
https://www.nwcg.gov/publications/pms205/nwcg-glossary-of-wildland-fire-pms-205; NIFC External Affairs,
“Communicating Fire: Telling the Story Clearly, Consistently, and Professionally,” https://www.nifc.gov/sites/
default/files/document-media/CommunicatingFire-NIFC.pdf; Mary Taber et al., Decision Making for Wildfires: A
Guide for Applying a Risk Management Process at the Incident Level, USDA, FS, Gen. Tech. Rep. RMRS-GTR298WWW, June 2013, https://wfmrda.nwcg.gov/sites/default/files/docs/WFMRDA/Publications/Decision_
Making_Wildfires_rmrs_gtr298.pdf. For additional information on terminology surrounding use of wildland
fire, see Rachel Bean and Alexander Evans, Managed Wildfire: A Research Synthesis and Overview, Northern
Arizona University Ecological Restoration Institute, 2023.
Qualified personnel or land owners might ignite prescribed fires in predetermined locations,
under predetermined conditions, to meet desired resource objectives. To plan a prescribed fire,
typically a specialist prepares a burn plan with criteria such as fuel moisture, wind speed, relative
humidity, and smoke management that will determine the burn window, when a prescribed burn
can occur.49 These criteria in a burn plan are intended to maximize the likelihood of safely
meeting objectives for the burn. In addition, prescribed burning generally is subject to various
legal requirements, such as personnel qualifications, permitting, and liability considerations.
The costs of use of wildland fire are variable and, in some ways, unpredictable. Generally,
researchers have found that use of wildland fire tends to be more cost-effective per acre than
other fuels mitigation approaches.50 However, ultimate costs for prescribed fires or use of
49 NWCG, NWCG Prescribed Fire Plan Template, PMS 484-1, December 2021, https://www.nwcg.gov/publications/
pms484-1; USDA, FS, Pacific Southwest Region, “Forest Service Professionals Prepare for a Prescribed Burn,” April
4, 2023, https://www.fs.usda.gov/about-agency/features/professionals-prepare-for-prescribed-burn; Texas A&M Forest
Service, “Writing a Burn Plan,” accessed August 16, 2025, https://tfsweb.tamu.edu/forest-land/prescribed-fire/
prescribed-burning-burn-managers/writing-a-burn-plan/.
50 Timothy G. Holland et al., “The Management Costs of Alternative Forest Management Strategies in the Lake Tahoe
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wildland fires are difficult to predict for several reasons. For example, fires that escape
containment are subject to suppression costs, leading to overall uncertainty regarding costs of use
of wildland fire. Other considerations include the resource needs to monitor and contain the fire,
the impact of burning on future wildfire risk, and the impact of the fire on long-term maintenance
needs.51
A century of fire suppression in the United States has led to fuel buildup in many ecosystems.
Many researchers assert that a policy of suppressing all fires will lead to less safe burn conditions
in the long run, with larger and more severe fires.52 Although all fire carries safety risks, fire often
brings ecological benefits, such as restoring soil nutrients and supporting fire-adapted species.53
Cultural Burning
Cultural burning refers to the Indigenous practice of cultivating fire on the landscape and was a
part of life for many Native Americans for millennia.54 Cultural burning might be applied for
fuels mitigation or other purposes. The reasons for cultural burns will vary between cultural
affiliations. The Karuk Tribe, one Tribe that engages in cultural burning, offers this definition:
Cultural burning is typically less formal [than prescribed burning], and is integrative of
holistic knowledge of place to guide the timing and implementation of burning activities.
Cultural burning implies the purposeful use of fire by a cultural group (e.g., family unit,
Tribe, clan/moiety, society) for a variety of purposes and outcomes. The reasons for
cultural burning can be quite extensive and range from maintenance of travel corridors,
Basin,” Ecology & Society, vol. 27, no. 4 (2022) (hereinafter Holland et al., “Management Costs of Alternative
Strategies”); Malcolm P. North et al., “Reform Forest Fire Management: Agency Incentives Undermine Policy
Effectiveness,” Science, vol. 349, no. 6254 (September 18, 2015), pp. 1280-1281 (hereinafter North et al., “Reform
Forest Fire Management”); Alan A. Ager et al., “Tradeoffs Between U.S. National Forest Harvest Targets and Fuel
Management to Reduce Wildfire Transmission to the Wildland Urban Interface,” Forest Ecology and Management,
vol. 434 (February 28, 2019), pp. 99-109 (hereinafter Ager et al., “Tradeoffs Between Targets and Fuel Management”).
51 Bruce R. Hartsough et al., “The Economics of Alternative Fuel Reduction Treatments in Western United States Dry
Forests: Financial and Policy Implications from the National Fire and Fire Surrogate Study,” Forest Policy and
Economics, vol. 10, no. 6 (August 2008), pp. 344-354 (hereinafter Hartsough et al., “Economics of Fuel Reduction
Treatments”); Hayley Hesseln, “The Economics of Prescribed Burning: A Research Review,” Forest Science, vol. 46,
no. 3 (2000), pp. 322-334; Holland et al., “Management Costs of Alternative Strategies”; James McIver et al., Principal
Short-Term Findings of the National Fire and Fire Surrogate Study, USDA, FS, Pacific Northwest Research Station,
General Technical Report PNW-GTR-860, 2012, https://www.fs.usda.gov/pnw/pubs/pnw_gtr860.pdf (hereinafter
McIver et al., National Fire and Fire Surrogate Study); D. Evan Mercer et al., “Evaluating Alternative Prescribed
Burning Policies to Reduce Net Economic Damages from Wildfire,” American Journal of Agricultural Economics, vol.
89, no. 1 (2007); Michael H. Taylor et al., “The Economics of Fuel Management: Wildfire, Invasive Plants, and the
Dynamics of Sagebrush Rangelands in the Western United States,” Journal of Environmental Management, vol. 126
(2013), pp. 157-173; David Wear et al., The Costs of Achieving Forest Resilience in California, Resources for the
Future, Working Paper 25-03, January 2025, pp. 16, 18, https://media.rff.org/documents/WP_25-03.pdf (hereinafter
Wear et al., Costs of Achieving Forest Resilience).
52 Mark R. Kreider et al., “Fire Suppression Makes Wildfires More Severe and Accentuates Impacts of Climate Change
and Fuel Accumulation,” Nature Communications, vol. 15, no. 2412 (March 25, 2024); North et al., “Reform Forest
Fire Management”; Tony Schick and Jes Burns, “Efforts to Reduce Wildfire Risk Fall Short, Buck Science,” Oregon
Public Broadcasting, July 16, 2018.
53 McLauchlan et al., “Fire as a Fundamental Process”; He et al., “Fire as a Key Driver of Earth’s Biodiversity,”
Biological Reviews, vol. 94, no. 6 (December 2019), pp. 1983-2010 (hereinafter He et al., “Fire as a Key Driver of
Earth’s Biodiversity”).
54 See, for example, NPS, “Indigenous Fire Practices Shape Our Land,” March 18, 2024, https://www.nps.gov/subjects/
fire/indigenous-fire-practices-shape-our-land.htm.
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wildlife habitat improvement, attracting wildlife to a place, water stewardship, pest control,
stewardship of cultural plants, conservation/protection, and even spiritual reasons. 55
WFMAs might collaborate with federally recognized Tribes (hereinafter Tribes) or provide
assistance for tribal members to enact cultural burns.56 Some have recommended that federal
agencies develop new procedures to proactively cooperate with cultural practitioners.57 Cultural
burning as historically practiced may be difficult to implement across some jurisdictions but may
inform agency practices, or Tribes might be able to carry out burns with modifications in some
cases.
Benefits and Risks of Use of Wildland Fire
Various reasons influence the choice to use fire as a fuels management technique. Some
advantages of fire over other fuels management techniques include the following:
•
•
•
Use of wildland fire tends to impede future fire progression or extent, and
subsequent fires generally burn with reduced severity.58
Fire may achieve certain ecological benefits or achieve them more easily than
other means. For example, fire can affect soil properties, plant growth, and insect
populations.59 Some species rely on fire; hence management goals related to
these species may not be achieved through non-fire means.60
Under certain conditions, fire can reduce surface fuel loading and continuity
across a large area, even in remote or difficult terrain.61
55 Sara A. Clark et al., Good Fire: Current Barriers to the Expansion of Cultural Burning and Prescribed Fire in
California and Recommended Solutions, Karuk Tribe, June 17, 2022, p. 3,
https://karuktribeclimatechangeprojects.wordpress.com/wp-content/uploads/2022/06/karuk-prescribed-fire-rpt_
2022_v2-1.pdf (hereinafter Clark et al., Good Fire).
56 A federally recognized Tribe is an entity that is generally “eligible for the special programs and services provided by
the United States to Indians because of their status as Indians” (25 C.F.R. §83.2).
57 Clark et al., Good Fire.
58 C. Alina Cansler et al., “Previous Wildfires and Management Treatments Moderate Subsequent Fire Severity,”
Forest Ecology and Management, vol. 504 (January 15, 2022); Theresa B. Jain et al., Final Report: Effectiveness of
Fuel Treatments at the Landscape Scale: State of Understanding and Key Research Gaps, USDA, FS, RMRS, Joint
Fire Sciences Program (JFSP) Project ID 19-S-01-2, December 2021 (hereinafter Jain et al., Effectiveness of Fuel
Treatments); Sean A. Parks et al., “Wildland Fire as a Self-Regulating Mechanism: The Role of Previous Burns and
Weather in Limiting Fire Progression,” Ecological Applications, vol. 25, no. 6 (September 2015) (hereinafter Parks et
al., “Fire as a Self-Regulating Mechanism”); Elizabeth L. Kalies and Larissa L. Yocom Kent, “Tamm Review: Are
Fuel Treatments Effective at Achieving Ecological and Social Objectives? A Systemic Review,” Forest Ecology and
Management, vol. 375 (September 1, 2016), p. 7 (hereinafter Kalies and Yocom Kent, “Tamm Review: Fuel
Treatments Objectives”); Rachel Bean and Alexander Evans, Managed Wildfire: A Research Synthesis and Overview,
Northern Arizona University Ecological Restoration Institute, 2023 (hereinafter Bean and Evans, Managed Wildfire
Research Synthesis); Kimberley T. Davis et al., “Tamm Review: A Meta-Analysis of Thinning, Prescribed Fire, and
Wildfire Effects on Subsequent Wildfire Severity in Conifer Dominated Forests of the Western U.S.,” Forest Ecology
and Management, vol. 561 (April 2024) (hereinafter Davis et al., “Tamm Review: Effects on Wildfire Severity”);
Susan J. Prichard et al., “Adapting Western North American Forests to Climate Change and Wildfires: 10 Common
Questions,” Ecological Applications, vol. 31, no. 8 (December 2021).
59 McLauchlan et al., “Fire as a Fundamental Process”; He et al., “Fire as a Key Driver of Earth’s Biodiversity”;
McIver et al., National Fire and Fire Surrogate Study.
60 McLauchlan et al., “Fire as a Fundamental Process”; He et al., “Fire as a Key Driver of Earth’s Biodiversity.”
61 Eric E. Knapp et al., “Fuel Reduction and Coarse Woody Debris Dynamics with Early Season and Late Season
Prescribed Fire in a Sierra Nevada Mixed Conifer Forest,” Forest Ecology and Management, vol. 208 (2005), pp. 383397.
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•
Fire reduces surface fuels without additional actions, and fire can reduce fuels
remaining on the ground after mechanical or herbicide treatments.
Conversely, some disadvantages of fire as a hazardous fuels mitigation technique include the
following:
•
•
•
•
Fire presents a risk to life, property, and other resources and values if wildland
fires escape containment.62 Such fires are then wildfires, with all the costs and
risks associated with fire suppression. Despite these risks and examples of when
escaped fires have ended in tragedy, the FS points out that of approximately
4,500 prescribed fires per year, more than 99% go as planned.63 However, the
risk may affect public perception and lead to political and liability concerns,
causing fire managers to refrain from using wildland fire.64
The use of wildland fire is acceptable in only limited locations, times, and
situations. Use of wildland fire depends on biophysical factors (e.g., weather),
social factors (e.g., smoke impacts to communities), or a combination. These
factors mean that some areas or some years may have very short burn windows
when use of wildland fire is feasible.
The use of wildland fire on federal lands is subject to the availability of qualified
personnel and resources. In certain areas or at certain times (e.g., during wildfire
season), this factor may limit use of wildland fire.65
In addition to other considerations, smoke can be a significant health hazard
during use of wildland fire. Research has associated wildfire smoke exposure
with cardiovascular, respiratory, and brain diseases.66 Several federal agencies
62
For example, in 2022, two fires in New Mexico—Calf Canyon and Cerro Pelado—started when burned piles of slash
remaining after mechanical treatments reignited months later. A third prescribed fire, Hermits Peak, escaped and
merged with Calf Canyon. Altogether, the fires burned nearly 400,000 acres and several hundred homes, spurring the
FS to temporarily pause all prescribed burns and review its national prescribed fire program. USDA, FS, National
Prescribed Fire Program Review, September 2022, https://www.frames.gov/documents/usfs/USFS_20220908_
National-Prescribed-Fire-Program-Review.pdf (hereinafter USDA, FS, National Prescribed Fire Program Review). In
2025, the Dragon Bravo fire in Arizona burned more than 145,500 acres and destroyed more than 113 structures,
including the historic Grand Canyon Lodge, prompting closure of Grand Canyon National Park’s North Rim. The fire
was a natural ignition that the NPS initially managed for resource objectives, but the fire escaped containment. NIFC,
“Incident Management Situation Report, Wednesday, August 20, 2025—0730 MDT,” accessed August 20, 2025,
https://www.nifc.gov/nicc-files/sitreprt.pdf; NPS, Grand Canyon National Park, “Grand Canyon National Park
Temporarily Closes North Rim Due to White Sage Fire,” July 10, 2025, https://perma.cc/9HJV-LNVP; NPS, Grand
Canyon National Park, “Grand Canyon National Park Update on Dragon Bravo Fire,” July 13, 2025,
https://perma.cc/26L6-NNU4; Inciweb, “Dragon Bravo Fire Update - Last Update Unless Significant Activity Occurs
09-17-2025,” https://inciweb.wildfire.gov/incident-publication/azgcp-dragon-bravo-fire/dragon-bravo-fire-update-lastupdate-unless-significant-activity-occurs-09-17-2025.
63
USDA, FS, National Prescribed Fire Program Review, p. 3.
64 Bean and Evans, Managed Wildfire Research Synthesis; USDA, FS, Barriers to Prescribed Fire Implementation,
Possible Solutions, and an Estimate of Fire Damage in Calendar Year 2021 That Could Potentially Have Been
Avoided, https://www.fs.usda.gov/sites/default/files/fy22-prescribed-burns-report.pdf (hereinafter USDA, FS, Barriers
to Prescribed Fire Implementation). This report was produced by the FS in response to congressional direction in P.L.
117-103.
65 For example, see USDA, FS, Barriers to Prescribed Fire Implementation. See also Wildland Fire Commission, On
Fire, pp. 21-25, 162-191.
66 Rosana Aguilera et al., “Wildfire Smoke Impacts Respiratory Health More Than Fine Particles from Other Sources:
Observational Evidence from Southern California,” Nature Communications, vol. 12, no. 1493 (March 5, 2021); Hao
Chen et al., “Cardiovascular Health Impacts of Wildfire Smoke Exposure,” Particle and Fibre Toxicology, vol. 18, no.
2 (January 7, 2021); Colleen E. Reid et al., “Critical Review of Health Impacts of Wildfire Smoke Exposure,”
(continued...)
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•
•
•
provide information about wildfire smoke, including real-time maps, to assist
with local outreach and mitigation.67
Fire is an imprecise tool compared with some other techniques for reducing fuels.
For example, fire managers cannot control fire’s effects on postfire forest
structure as accurately as they can control the effects of some mechanical or
chemical approaches.68
As with some other approaches, effects decrease with time after the treatment.69
The ability of previous fires to impede future fire progression or extent decreases
during extreme fire weather conditions.70
Mechanical Treatments
Mechanical treatments involve the manipulation, and may also include the removal, of hazardous
fuels with tools and equipment, such as hand tools, chainsaws, and heavy machinery. Mechanical
fuel treatments rearrange and resize fuels by cutting down biomass and redistributing it to the
surface. The fuel loading is not decreased unless fuels crews remove the cut biomass after the
treatment. Crews can remove fuels from the site, redistribute them on the surface, burn them, or
some combination of these approaches.
Mechanical treatments can incorporate a variety of techniques, including the following:
•
•
•
Thinning is the process of systematically removing part of a stand of trees to
reduce stand density and break up horizontal continuity, among other goals.
Thinning from below involves removing small trees and ladder fuels to break up
vertical continuity.
Timber harvesting is “the removal of trees for wood fiber use and other multipleuse purposes.”71 Managers can perform timber harvesting with a range of
intensity, from a clearcut or regeneration harvest (removal of all trees) to
selective harvest (removal of trees of a specific size, age, species, or condition or
in different arrangements across the landscape). Timber harvesting can include
salvage: harvest of dead, diseased, fallen, or damaged trees. Timber harvesting
differs from thinning in that growth of new trees is a primary goal.
Mastication involves using specialized equipment to grind trees or shrubs into
small pieces to reduce fuel continuity and rearrange the fuel load, among other
goals. It is sometimes used to remove specific species.72
Environmental Health Perspectives, vol. 124, no. 9 (April 15, 2016), pp. 1334-1343; Holly Elser et al., “Wildfire
Smoke Exposure and Incident Dementia,” JAMA Neurology, vol. 82, no. 1 (November 25, 2024); Wildland Fire
Commission, “Protecting Public Health,” in On Fire, pp. 83-105.
67 AirNow, “Wildfires,” https://www.airnow.gov/wildfires/, a centralized repository for data from the Environmental
Protection Agency (EPA) and other federal, state, local, and international agencies.
68 Bean and Evans, Managed Wildfire Research Synthesis.
69 Davis et al., “Tamm Review: Effects on Wildfire Severity”; Jain et al., Effectiveness of Fuel Treatments, p. 15; Parks
et al., “Fire as a Self-Regulating Mechanism.”
70 Jain et al., Effectiveness of Fuel Treatments, p. 22; Parks et al., “Fire as a Self-Regulating Mechanism.”
71 USDA, FS, “Silvicultural Practices,” in Forest Service Manual FSM 2400—Forest Management, WO Amendment
2400-2014-1, March 6, 2014, pp. 10-18, https://www.fs.usda.gov/about-agency/regulations-policies/manual/2470silvicultural-practices.
72 Theresa Jain et al., To Masticate or Not: Useful Tips for Treating Forest, Woodland, and Shrubland Vegetation,
USDA, FS, RMRS, RMRS-GTR-381, September 2018, https://doi.org/10.2737/RMRS-GTR-381.
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•
Mowing is reducing the height of surface vegetation with mechanized equipment.
Mowing can rearrange flash fuel loads or reduce live fuels.73
Mechanical treatments produce debris (aka slash). Slash may be a by-product of the treatment
(e.g., limbs and bark left over from timber harvesting), or it may be the primary result of the
treatment (e.g., mastication). Slash is itself a wildfire fuel; thus, slash management is an
important consideration in mechanical fuel treatments.74 Options for slash management include
redistributing by spreading or mulching or removing through burning or hauling.
Advantages and Disadvantages of Mechanical Treatments
Various factors influence the choice of whether and how to use mechanical treatments as a fuels
mitigation technique. Some advantages of mechanical treatments over other fuels management
techniques include the following:
•
•
•
•
Some mechanical fuel treatments reduce future fire severity, within and beyond
the actual areas treated.75
Mechanical treatments allow precise manipulation of fuels in a defined area.
Mechanical treatments may be used in situations where use of wildland fire is
excluded or risky due to biophysical and social factors, such as weather, fuel
conditions, or proximity to communities. Mechanical treatments sometimes
prepare land for use of wildland fire.76
In some cases, the costs of mechanical treatments can be offset with the sale of
marketable forest products.77 This may allow fuel treatments to be conducted that
otherwise would be limited or forgone due to resource availability.
Conversely, some disadvantages of mechanical fuel treatments include the following:
73 Jesse Kreye et al., Mechanical Treatments in Pine Flatwoods: A Temporary Rearrangement of Fuel Structure,
Southern Fire Exchange, SFE Fact Sheet 2015-1, January 22, 2021, https://southernfireexchange.org/wp-content/
uploads/2015-1.pdf; Lisa M. Ellsworth et al., “Fuel Reduction Treatments Reduce Modeled Fire Intensity in the
Sagebrush Steppe,” Ecosphere, vol. 13, no. 5 (May 12, 2022) (hereinafter Ellsworth et al., “Fuel Treatments Reduce
Modeled Intensity”).
74 Valerie Rapp, Tested by Fire: What Happens When Wildfires Meet Fuel Treatments? USDA, FS, JFSP, JFSP Briefs
no. 1, October 2007, https://digitalcommons.unl.edu/cgi/viewcontent.cgi? article=1052&context=jfspbriefs; Susan J.
Prichard et al., “Fuel Treatments Reduce the Severity of Wildfire Effects in Dry Mixed Conifer Forest, Washington,
USA,” Canadian Journal of Forest Research, vol. 40 (2010), pp. 1615-1626 (hereinafter Prichard et al., “Fuel
Treatments Reduce Severity of Wildfire Effects”); Kalies and Yocom Kent, “Tamm Review: Fuel Treatments
Objectives”; Ager et al., “Tradeoffs Between Targets and Fuel Management”; Emily Brodie et al., “Forest Thinning
and Prescribed Burning Treatments Reduce Wildfire Severity and Buffer the Impacts of Severe Fire Weather,” Fire
Ecology, vol. 20, no. 1 (February 2024); Jesse K. Kreye et al., “Fire Behavior in Masticated Fuels: A Review,” Forest
Ecology and Management, vol. 314 (February 15, 2014), pp. 193-207; Brett H. Wolk et al., Mulching: A Knowledge
Summary and Guidelines for Best Practices on Colorado’s Front Range, Colorado Forest Restoration Institute, CFRI2001, January 2020, pp. 8-9, https://www.fs.usda.gov/rm/pubs_journals/2020/rmrs_2020_wolk_b001.pdf.
75 Hugh D. Safford et al., “Effects of Fuel Treatments on Fire Severity in an Area of Wildland-Urban Interface, Angora
Fire, Lake Tahoe Basin, California,” Forest Ecology and Management, vol. 258, no. 5 (August 20, 2009), pp. 773-787;
Barbara A. Strom and Peter Z. Fule, “Pre-Wildfire Fuel Treatments Affect Long-Term Ponderosa Pine Forest
Dynamics,” International Journal of Wildland Fire, vol. 16 (February 20, 2007), pp. 128-138; James D. Johnston et al.,
“Mechanical Thinning Without Prescribed Fire Moderates Wildfire Behavior in an Eastern Oregon, USA Ponderosa
Pine Forest,” Forest Ecology and Management, vol. 501 (December 1, 2021).
76 Davis et al., “Tamm Review: Effects on Wildfire Severity”; Kalies and Yocom Kent, “Tamm Review: Fuel
Treatments Objectives.”
77 Holland et al., “Management Costs of Alternative Strategies”; Hartsough et al., “Economics of Fuel Reduction
Treatments”; Wildland Fire Commission, “Mitigation Through Mechanical Treatments,” in On Fire, pp. 63-68.
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•
•
•
•
•
•
The effectiveness of mechanical treatments depends on the ability to address
certain fuel types (e.g., ladder fuels, surface fuels, slash). Studies indicate that
mechanical fuel treatments alone are not effective unless accompanied by use of
wildland fire or other removal of surface fuels.78
Heavy equipment used in some mechanical treatments may have negative
environmental impacts, such as contributing to erosion and soil compaction,
disturbing wildlife and surface-level plants, or contributing to invasive species
spread.
Mechanical treatments require physical access to the entire area being treated,
which may exclude or limit use in rugged, sensitive, or remote terrain.
Fuel treatment costs are highly variable. Mechanical treatments tend to be more
costly to conduct than prescribed fire, though in some cases the costs of
mechanical treatments can be offset with the sale of harvested forest products.79
Mechanical treatments do not replace all of fire’s ecological roles in fire-adapted
systems.80
As with some other approaches, effects decrease with time.81
Biological and Chemical Approaches
Targeted Grazing
A commonly cited definition of targeted grazing comes from the American Sheep Industry
Association: “the application of a particular kind of grazing animal at a specified season,
duration, and intensity to accomplish specific vegetation management goals.”82 Targeted grazing
differs from normal livestock grazing because the goal is vegetation management instead of
animal production.83 Concentrated livestock consume and trample fine fuels.84 Targeted grazing
is most commonly applied to create fuel breaks in grassland and shrubland systems (see “Fuel
Breaks and Firebreaks”), though other applications include general fuel load reduction, reducing
fire-adapted non-native species, and fuels mitigation in forested systems.85
78 Davis et al., “Tamm Review: Effects on Wildfire Severity”; McIver et al., National Fire and Fire Surrogate Study;
Prichard et al., “Fuel Treatments Reduce Severity of Wildfire Effects”; Kalies and Yocom Kent, “Tamm Review: Fuel
Treatments Objectives.”
79 Wear et al., Costs of Achieving Forest Resilience; Holland et al., “Management Costs of Alternative Strategies”;
Hartsough et al., “Economics of Fuel Reduction Treatments”; Wildland Fire Commission, “Mitigation Through
Mechanical Treatments,” in On Fire, pp. 63-68.
80 McLauchlan et al., “Fire as a Fundamental Process”; He et al., “Fire as a Key Driver of Earth’s Biodiversity.”
81 Davis et al., “Tamm Review: Effects on Wildfire Severity”; Parks et al., “Fire as a Self-Regulating Mechanism.”
82 Rachel Frost et al., “Targeted Grazing: Applying the Research to the Land,” Rangelands, vol. 34, no. 1 (February
2012) (hereinafter Frost et al., “Targeted Grazing Research”), italics in original. See also Dan Macon, Targeted
Grazing: A Primer for Consumers, University of California Agriculture and Natural Resources Cooperative Extension,
Publication Number 31-1002, February 2018, https://ucanr.edu/sites/default/files/2018-05/279408.pdf (hereinafter
Macon, Targeted Grazing Primer); Wildland Fire Commission, “Mitigation Through Grazing,” in On Fire, pp. 69-71.
83 Frost et al., “Targeted Grazing Research”; Macon, Targeted Grazing Primer.
84 Derek W. Bailey et al., “Synthesis Paper: Targeted Livestock Grazing—Prescription for Healthy Rangelands,”
Rangeland Ecology & Management, vol. 72, no. 6 (November 2019) (hereinafter Bailey et al., “Synthesis Paper:
Targeted Livestock Grazing”).
85 Charles A. Taylor Jr., “Targeted Grazing to Manage Fire Risk,” in Targeted Grazing: A Natural Approach to
(continued...)
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Targeted grazing has a different business model from traditional livestock production:86 (1) the
livestock operators’ income is tied to providing a service;87 (2) animals need to be concentrated at
high enough levels to sufficiently reduce fuels and may not receive optimal nutrition;88
(3) operators may need to provide additional feed;89 (4) operators try to confine the animals with
supplements or water sources but sometimes require more costly methods, such as temporary
fencing or herding;90 and (5) they remove the animals when fuels are depleted.
Some stakeholders propose a general increase in livestock grazing in fire-prone landscapes to
reduce hazardous fuels instead of, or in addition to, targeted grazing.91 A discussion of the
potential positive and negative effects, including ecological effects, of broadly increasing
livestock grazing in fire-prone landscapes is beyond the scope of this report.
Advantages of targeted grazing include the following:
•
•
•
•
Targeted grazing can be applied to small parcels and within urban areas where
use of wildland fire would be risky.92
Targeted grazing can be cost effective and scalable.93
Targeted grazing can be applied in steep and remote areas where mowing or
chemical applications are impractical.94
Properly applied, targeted grazing can reduce fine surface fuels and low ladder
fuels, decreasing fire intensity.95
Vegetation Management and Landscape Enhancement, eds. Karen L. Launchbaugh et al. (American Sheep Industry
Association, 2006) (hereinafter Taylor, “Targeted Grazing to Manage Fire Risk”); Patrick E. Clark et al., “Evaluating
the Efficacy of Targeted Cattle Grazing for Fuel Break Creation and Maintenance,” Rangeland Ecology &
Management, vol. 89 (July 2023); Kirk W. Davies et al., “Ecological Benefits of Strategically Applied Livestock
Grazing in Sagebrush Communities,” Ecosphere, vol. 15, no. 5 (May 22, 2024) (hereinafter Davies et al., “Ecological
Benefits of Strategically Applied Livestock Grazing”); Christopher L. Schachtschneider et al., “Targeted Cattle
Grazing to Alter Fuels and Reduce Fire Behavior Metrics in Shrub-Grasslands,” Rangeland Ecology & Management,
vol. 96 (August 20, 2024), pp. 105-116 (hereinafter Schachtschneider et al., “Targeted Cattle Grazing to Reduce Fire
Behavior”).
86 Macon, Targeted Grazing Primer; Frost et al., “Targeted Grazing Research.”
87 Macon, Targeted Grazing Primer; Frost et al., “Targeted Grazing Research.”
88 Bailey et al., “Synthesis Paper: Targeted Livestock Grazing.”
89
Frost et al., “Targeted Grazing Research.”
90 Bailey et al., “Synthesis Paper: Targeted Livestock Grazing”; Frost et al., “Targeted Grazing Research.”
91 For example, see Cattlemen’s Foundation and California Cattle Council, “Cattle Grazing Is Key to Mitigating
Wildfires,” https://calcattlecouncil.org/wp-content/uploads/2024/01/Foundation-Wildfire-Factsheet-Final.pdf; Felix
Ratcliff et al., “Cattle Grazing Reduces Fuel and Leads to More Manageable Fire Behavior,” California Agriculture,
vol. 76, no. 2-3 (April 2022); Genoa I. Starrs et al., “Quantifying Large-Scale Impacts of Cattle Grazing on Annual
Burn Probability in Napa and Sonoma Counties, California,” Ecology and Society, vol. 29, no. 3 (2024).
92 Frost et al., “Targeted Grazing Research.”
93 Davies et al., “Ecological Benefits of Strategically Applied Livestock Grazing.”
94 Macon, Targeted Grazing Primer.
95 Davies et al., “Ecological Benefits of Strategically Applied Livestock Grazing”; Schachtschneider et al., “Targeted
Cattle Grazing to Reduce Fire Behavior”; Taylor, “Targeted Grazing to Manage Fire Risk.”
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•
Targeted grazing can reduce undesirable species in the short term (one or two
years).96 A combination of fire and targeted grazing might control non-native
annual grasses, some of which increase fire probability and frequency.97
Conversely, disadvantages of targeted grazing as a hazardous fuels mitigation technique include
the following:
•
•
•
•
Livestock foraging preferences could change species composition of the
understory, sometimes in undesirable ways.98
Timing is critical to success. There may be a short window of time when plant
life cycles, palatability, weather, and other factors properly align.99 Targeted
grazing may take multiple years to have a measurable outcome.100
Targeted grazing is not recommended in areas with woody stems and shrubs,
because (1) cattle and goats do not remove woody stems and shrubs and
(2) woody plants mixed with grasses burn at high intensity and spread fire
quickly.101 Improperly applied, targeted grazing could provide a competitive
advantage to woody plants.102
Livestock are unlikely to limit crown fires, especially during severe winds and
low fuel moistures.103
96 Katherine M. Marchetto et al., “The Effectiveness of Using Targeted Grazing for Vegetation Management: A Meta-
Analysis,” Restoration Ecology, vol. 29, no. 5 (July 2021), p. 8 (hereinafter Marchetto et al., “Effectiveness of Targeted
Grazing for Vegetation Management”).
97 Hongwei Wan et al., “Selective Grazing and Seasonal Precipitation Play Key Roles in Shaping Plant Community
Structure of Semi-Arid Grasslands,” Landscape Ecology, vol. 30 (August 6, 2015); Joel M. Diamond et al., “Effects of
Targeted Grazing and Prescribed Burning on Community and Seed Dynamics of a Downy Brome (Bromus tectorum)–
Dominated Landscape,” Invasive Plant Science and Management, vol. 5, no. 2 (January 20, 2017); Matthew L. Brooks
et al., “Effects of Invasive Alien Plants on Fire Regimes,” BioScience, vol. 54, no. 7 (July 2004) (hereinafter Brooks et
al., “Effects of Alien Plants”); Bradley et al., “Cheatgrass and Fire.”
98 Mark Batcheler et al., “Assessing Silvopasture Management as a Strategy to Reduce Fuel Loads and Mitigate
Wildfire Risk,” Scientific Reports, vol. 14 (March 12, 2024); Gina R. Beebe et al., “Fire Versus Herbivory for Oak
Woodland Restoration: Burning Achieves Short-Term Structural and Compositional Objectives Whereas Browsing
Alone Fails to Reduce Stem Densities and Promote Ground Flora,” Fire Ecology, vol. 20, no. 102 (November 20,
2024) (hereinafter Beebe et al., “Browsing Alone Fails to Reduce Stem Densities”); Davies et al., “Ecological Benefits
of Strategically Applied Livestock Grazing.”
99 Bailey et al., “Synthesis Paper: Targeted Livestock Grazing”; Frost et al., “Targeted Grazing Research.”
100 Beebe et al., “Browsing Alone Fails to Reduce Stem Densities”; USDA Climate Hubs, “Targeted Grazing for
Wildfire Fuel Breaks,” accessed May 4, 2025, https://perma.cc/NJX4-PHV5; Devyn A. Orr et al., “Grazing Intensity
Effects of Fire Ignition Risk and Spread in Sagebrush Steppe,” Rangeland Ecology & Management, vol. 89 (July
2023); Davies et al., “Ecological Benefits of Strategically Applied Livestock Grazing”; Theresa B. Jain et al., “A
Comprehensive Guide to Fuel Management Practices for Dry Mixed Conifer Forests in the Northwestern United
States,” USDA, FS, RMRS, Research Note RMRS-RN-61, 2014, p. 1, https://www.fs.usda.gov/rm/pubs/
rmrs_rn061.pdf (hereinafter Jain et al., “Guide to Fuel Management Practices”).
101 Schachtschneider et al., “Targeted Cattle Grazing to Reduce Fire Behavior”; Taylor, “Targeted Grazing to Manage
Fire Risk”; Beebe et al., “Browsing Alone Fails to Reduce Stem Densities”; Davies et al., “Ecological Benefits of
Strategically Applied Livestock Grazing”; Victoria M. Donovan et al., “Targeted Grazing and Mechanical Thinning
Enhance Forest Stand Resilience Under a Narrow Range of Wildfire Scenarios,” Ecosphere, vol. 13, no. 5 (May 12,
2022) (hereinafter Donovan et al., “Targeted Grazing and Mechanical Thinning Enhance Resilience”); Casey Matzke,
“Grazing Against the Flames: Using Targeted Grazing to Combat Wildfires,” Texas A&M AgriLife Extension, West
Texas Rangelands, April 9, 2025, https://agrilife.org/westtexasrangelands/grazing-against-the-flames-using-targetedgrazing-to-combat-wildfires/.
102 Davies et al., “Ecological Benefits of Strategically Applied Livestock Grazing.”
103 Beebe et al., “Browsing Alone Fails to Reduce Stem Densities”; Schachtschneider et al., “Targeted Cattle Grazing
to Reduce Fire Behavior”; Donovan et al., “Targeted Grazing and Mechanical Thinning Enhance Resilience.”
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•
Targeted grazing may not provide long-term control for undesirable species,
which recover one to two years after targeted grazing ends.104
Herbicide Application
Herbicide application is the controlled use of chemicals to kill or suppress unwanted vegetation.
Some common uses for herbicides in hazardous fuels control include reducing the presence of
specific undesirable species, clearing areas to bare soil, or creating fuel breaks (see “Fuel Breaks
and Firebreaks”). Right-of-way (ROW) holders sometimes use herbicides to remove vegetation
that could create an ignition risk within the ROW.105 Herbicides can be applied manually, with
vehicles, and aerially.
Personnel applying certain herbicides require licensing at the jurisdictional level where they make
the herbicide applications. The Environmental Protection Agency ensures applicator certification
programs meet minimum standards.106
Advantages of herbicide application include the following:
•
•
•
When properly applied, herbicides allow precise targeting of individual species
or locations. Herbicides can be applied to small parcels and within urban areas.
Herbicides allow treatment with no ground disturbance.
Herbicide application can be useful in combination with other methods, for
example to prepare for prescribed fire or to suppress resprouting woody species
after burning or thinning.107
Some disadvantages of herbicide use are as follows:
•
•
Herbicides must be applied in a manner consistent with their label, during the
correct phase of the plant lifecycle, and in specific weather conditions to
maximize efficacy and limit nontarget exposure.108
Herbicide application may take several years to reduce fuel loading, so additional
actions may be required to change fire hazard in the near term.109
104 Marchetto et al., “Effectiveness of Targeted Grazing for Vegetation Management.”
105 A right-of way (ROW) is a kind of easement, or non-possessory legal right to use or control land for a particular
purpose. An ROW provides a right to the easement holder to pass through property owned by another. For example, see
CRS In Focus IF12825, Rights-of-Way for Access On or Through Tribal Lands, by Mariel J. Murray and Benjamin M.
Barczewski.
106 EPA, Pesticide Worker Safety, “How to Get Certified as a Pesticide Applicator,” September 26, 2024,
https://www.epa.gov/pesticide-worker-safety/how-get-certified-pesticide-applicator.
107 Colorado State Forest Service, Colorado State University, Grassland Fuels Management, “Wildfire Fuels
Management Practices in Grass-Dominated Landscapes: An Overview of Fire Behavior, Management Practices and
Treatment Methods in Mixed-Grass Landscapes,” accessed May 4, 2025, https://csfs.colostate.edu/wildfire-mitigation/
grasslands/fuels/ (hereinafter Colorado State Forest Service, Colorado State University, “Wildfire Fuels Management in
Grass-Dominated Landscapes”; Douglas J. Marshall et al., Synthesis of Knowledge of Hazardous Fuels Management in
Loblolly Pine Forests, USDA, FS, Southern Research Station, General Technical Report SRS–110, November 2008,
pp. 9, 21-25, https://www.srs.fs.usda.gov/pubs/gtr/gtr_srs110.pdf.
108 For example, Arizona Department of Transportation (ADOT), ADOT Vegetation Management Guidelines—
Herbicides, pp. 23-24, https://azdot.gov/sites/default/files/2024-12/vegetation-management-guidelines-herbicideschapter.pdf.
109 Jain et al., “Guide to Fuel Management Practices”; Patrick Brose and Dale Wade, “Understory Herbicide as a
Treatment for Reducing Hazardous Fuels and Extreme Fire Behavior in Slash Pine Plantations,” in Proceedings of the
Eleventh Biennial Southern Silvicultural Research Conference, 2002, pp. 109-113, https://perma.cc/LN4V-X982;
(continued...)
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•
•
•
Herbicides leave dead fuels on the surface that may need removal to reduce
overall fuel loading.
Herbicide application may be controversial due to real or perceived dangers to
human and environmental health.110 Herbicides can harm some nontarget species
through spray drift, water contamination, direct toxicity to organisms, or habitat
removal.111
Herbicide application may cause a change in species composition, potentially
allowing undesirable frequent-fire species to establish.112
Fuel Breaks and Firebreaks
Fuel breaks are “a natural or manmade change in fuel characteristics which affects fire behavior
so that fires burning into them can be more readily controlled.”113 Fuel breaks can reduce ignition
potential, fire intensity, and rate of spread.114 Fuel breaks are often strategically located to create
places for firefighters to operate and protect values at risk. Shaded fuel breaks are a type of fuel
break that is “thinned and pruned to reduce the fire potential yet retain enough crown canopy to
make a less favorable microclimate for surface fires.”115
Firebreaks are “a natural or constructed barrier used to stop or check fires that may occur, or to
provide a control line from which to work.”116 Firebreaks tend to be areas where fuels are
completely removed down to the bare soil or a road and often are used in combination with fuel
Ellsworth et al., “Fuel Treatments Reduce Modeled Intensity”; Colorado State Forest Service, Colorado State
University, “Wildfire Fuels Management in Grass-Dominated Landscapes.”
110 Nicholas E. Korres, “Herbicide Effects on Humans: Exposure, Short and Long-Term Effects and Occupational
Hygiene,” in Weed Control: Sustainability, Hazards, and Risks in Cropping Systems Worldwide, eds. Nicholas E.
Korres et al. (CRC Press, 2018), pp. 14-31.
111 EPA, Causal Analysis/Diagnosis Decision Information System (CADDIS), “Herbicides,” February 7, 2025,
https://perma.cc/5AVN-6MW7; EPA, Office of Pesticide Programs, Office of Chemical Safety and Pollution
Prevention, Herbicide Strategy to Reduce Exposure of Federally Listed Endangered and Threatened Species and
Designated Critical Habitats from the Use of Conventional Agricultural Herbicides, EPA-HQ-OPP-2023-0365-1137,
August 2024, https://perma.cc/TUB4-3KS2.
112 Thomas W. McGinnis et al., “Fuel Buildup and Potential Fire Behavior After Stand-Replacing Fires, Logging FireKilled Trees and Herbicide Shrub Removal in Sierra Nevada Forests,” Forest Ecology and Management, vol. 260, no.
1 (June 2010); Brooks et al., “Effects of Alien Plants.”
113 NWCG Glossary. Fuel breaks are statutorily defined for the purpose of HFRA (16 U.S.C. §§6501 et seq.; 16 U.S.C.
§6511(2)(B)(i)). The definition in HFRA is not broadly applicable.
114 Benjamin Gannon et al., “A Quantitative Analysis of Fuel Break Effectiveness Drivers in Southern California
National Forests,” Fire, vol. 6, no. 3 (March 7, 2023) (hereinafter Gannon et al., “Quantitative Analysis of Fuel Break
Effectiveness”); Macarena Ortega et al., “Modeling Fuel Break Effectiveness in Southern Spain Wildfires,” Fire
Ecology, vol. 20 (April 23, 2024) (hereinafter Ortega et al., “Modeling Fuel Break Effectiveness”); Janine A. BaijnathRodino et al., “Quantifying the Effectiveness of Shaded Fuel Breaks from Ground-Based, Aerial, and Spaceborne
Observations,” Forest Ecology and Management, vol. 543 (September 2023) (hereinafter Baijnath-Rodino et al.,
“Effectiveness of Shaded Fuel Breaks”); Alexandra D. Syphard et al., “Comparing the Role of Fuel Breaks Across
Southern California National Forests,” Forest Ecology and Management, vol. 261, no. 11 (June 2011) (hereinafter
Syphard et al., “Comparing the Role of Fuel Breaks”); Cali L. Weise et al., “A Retrospective Assessment of Fuel Break
Effectiveness for Containing Rangeland Wildfires in the Sagebrush Biome,” Journal of Environmental Management,
vol. 341 (September 1, 2023) (hereinafter Weise et al., “Fuel Break Effectiveness in Sagebrush”).
115 NWCG Glossary.
116 NWCG Glossary. Firebreaks are statutorily defined for the purpose of HFRA (16 U.S.C. §6511(2)(B)(ii)). The
definition in HFRA is not broadly applicable.
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breaks.117 Firebreaks may be created as a precautionary measure before a fire starts or may be
created during firefighting operations.
Fuel breaks and firebreaks are most effective when fire suppression includes both aerial and
ground resources.118 These approaches will not stop fire spread without concomitant ground
operations.119 Fuel breaks function best within landscape-level treatments, especially prescribed
fire.120 They can be created and maintained with mechanical (e.g., mowing), biological (i.e.,
targeted grazing), and/or chemical methods.121
Potential advantages to creating fuel breaks include the following:
•
•
•
•
Strategically locating fuel breaks near WUI is likely to facilitate firefighting and
increase human safety.122
Fuel breaks can incorporate existing features, such as powerlines and roads.123
When fuel breaks are created with mechanical methods, the costs might be offset
with the sale of harvested forest products.124
Fuel breaks colocated with roads enable firefighter access and maintenance of the
fuel break.125
Potential disadvantages of fuel breaks include the following:
•
•
•
To serve as fire control lines, fuel breaks must provide firefighter access;
therefore, they may not function well in remote locations.126
Ecological degradation, including invasion by non-native species that increase
fire hazard, may occur when vegetation is completely or substantially removed to
create fuel breaks.127
Fuel breaks, similar to firebreaks, lose effectiveness in extreme weather.128
Firebrands may jump fuel breaks, spreading fires downwind.129
117 Ortega et al., “Modeling Fuel Break Effectiveness”; Gannon et al., “Quantitative Analysis of Fuel Break
Effectiveness.”
118 Pedro Belavenutti et al., “Multi-Objective Scheduling of Fuel Treatments to Implement a Linear Fuel Break
Network,” Fire, vol. 6, no. 1 (December 20, 2022) (hereinafter Belavenutti et al., “Multi-Objective Scheduling of Fuel
Treatments”); Ortega et al., “Modeling Fuel Break Effectiveness”; Baijnath-Rodino et al., “Effectiveness of Shaded
Fuel Breaks.”
119 Ortega et al., “Modeling Fuel Break Effectiveness”; Baijnath-Rodino et al., “Effectiveness of Shaded Fuel Breaks.”
120 Gannon et al., “Quantitative Analysis of Fuel Break Effectiveness.”
121 Bailey et al., “Synthesis Paper: Targeted Livestock Grazing.”
122 Syphard et al., “Comparing the Role of Fuel Breaks,” p. 2047.
123 Gannon et al., “Quantitative Analysis of Fuel Break Effectiveness.”
124 Belavenutti et al., “Multi-Objective Scheduling of Fuel Treatments.”
125 Gannon et al., “Quantitative Analysis of Fuel Break Effectiveness.”
126 Gannon et al., “Quantitative Analysis of Fuel Break Effectiveness”; Syphard et al., “Comparing the Role of Fuel
Breaks”; Weise et al., “Fuel Break Effectiveness in Sagebrush.”
127 Syphard et al., “Comparing the Role of Fuel Breaks,” p. 2047; Weise et al., “Fuel Break Effectiveness in
Sagebrush.”
128 Gannon et al., “Quantitative Analysis of Fuel Break Effectiveness”; Syphard et al., “Comparing the Role of Fuel
Breaks,” p. 2047; Weise et al., “Fuel Break Effectiveness in Sagebrush.”
129 Eunmo Koo et al., “Firebrands and Spotting Ignition in Large-Scale Fires,” International Journal of Wildland Fire,
vol. 19, no. 7 (November 5, 2010), pp. 818-843.
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•
The sale of forest products may not significantly offset costs of fuel breaks in all
cases, because the locations that maximize wildfire protection may provide lower
potential revenues, or the materials that need to be removed may have low value
(e.g., small trees and branches that compose ladder fuels).130
Maintenance
Some lands may benefit from multiple hazardous fuel treatments to maintain fire risk reduction,
especially to compensate for ongoing plant growth. Generally, treatments may reduce wildfire
severity in most forests for 10-20 years posttreatment and then must be repeated.131 Site-specific
conditions help determine the necessary maintenance intervals to protect homes in the WUI and
other values at risk in non-forested lands, such as grasslands and chaparral.132 Successful
maintenance of fuels mitigation measures may depend on whether and, if so, how well activities
are tracked and the extent to which resources are available to plan and perform regular
maintenance.
Federal Role and National Policies
Federal Role in Hazardous Fuels Mitigation
Hazardous fuels generally are managed by the landowner of the underlying land. Thus, the
federal role in hazardous fuels management varies in accordance with the underlying land
ownership. The federal government has a direct role in the management of forests in federal
ownership. The federal government’s role in managing nonfederal forests is indirect and
generally consists of providing financial, technical, or other assistance. In many situations,
various groups may collaborate to manage hazardous fuels in an area, particularly where land
ownership is commingled or adjacent. In such situations, authorities for collaboration, along with
authorities related to the underlying lands, become relevant.
Much of Congress’s legislative activity has focused on authorizing federal lands to be managed
and used for specific purposes. No federal law explicitly requires hazardous fuels mitigation from
a broad perspective. Instead, various statutes implicitly authorize the FS, BLM, NPS, and FWS to
mitigate hazardous fuels as part of their mandates to manage and protect the lands and resources
under their jurisdiction.133 Specific authorities also may direct, facilitate, or condition hazardous
fuels mitigation in certain circumstances; for example, the BIA can carry out “forest land
130 Belavenutti et al., “Multi-Objective Scheduling of Fuel Treatments.”
131 Davis et al., “Tamm Review: Effects on Wildfire Severity.”
132 Edith B. Allen et al., “Chaparral Restoration,” in Valuing Chaparral: Ecological, Socio-Economic, and
Management Perspectives, eds. Emma C. Underwood et al. (Springer, 2018); Radeloff et al., “Rising Wildfire Risk”;
Colorado State Forest Service, Colorado State University, “Wildfire Fuels Management in Grass-Dominated
Landscapes”; Weise et al., “Fuel Break Effectiveness in Sagebrush.”
133 For example, the FS is directed to “make provisions for the protection against destruction by fire” (16 U.S.C. §551);
the NPS’s purpose includes conservation of “the scenery, natural and historic objects, and wild life in the System units”
(54 U.S.C. §100101); the Federal Land Policy and Management Act (43 U.S.C. §§1701 et seq.) directs the Bureau of
Land Management to manage public lands “in a manner that will protect the quality of scientific, scenic, historical,
ecological, environmental, air and atmospheric, water resource, and archeological values” (43 U.S.C. §1701(a)(8)); and
the Fish and Wildlife Service is directed to administer the National Wildlife Refuge System to “ensure that the
biological integrity, diversity, and environmental health of the System are maintained for the benefit of present and
future generations of Americans (16 U.S.C. §668dd(a)(4)(B)).
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management activities” on Indian forest lands. These activities may include hazardous fuels
mitigation and actions to protect forest health.134
The Healthy Forests Restoration Act
Congress also has, at times, provided specific authorities related to hazardous fuels management
on federal lands. Prominent among these is HFRA, which pertains to the public lands managed by
BLM and to the National Forest System (NFS), managed by the FS.135 The pace and scale of
hazardous fuels management on these lands—the largest systems of federal forest land—have
been perennial congressional concerns. HFRA’s primary purpose is “to reduce wildfire risk ...
through a collaborative process of planning, prioritizing, and implementing hazardous fuel
reduction projects.”136 Thus, HFRA contains various provisions related to planning,
implementation, and administrative processes for specified land management projects on NFS
and BLM land, including hazardous fuel reduction projects. HFRA also includes various
provisions regarding grant programs, cross-boundary collaboration, and other items, some of
which are discussed in other sections of this report.
Under HFRA, authorized hazardous fuel reduction projects (as defined for the purposes of
HFRA) can be developed and implemented under a potentially expedited process in specified
areas of NFS and BLM land.137 These areas include NFS and BLM lands within the WUI; federal
lands in specified ecological conditions that are important for maintaining municipal water
supplies; and other federal lands in specified ecological conditions, such as departure from
historical fire regimes, where forest health is declining, or where fire could affect threatened and
endangered species survival.138 HFRA also specifies limitations on authorized projects, for
example, excluding projects within certain land designations and requiring particular ecological
considerations.139 HFRA includes various administrative provisions to potentially expedite such
projects, for example, project prioritization in specified areas and a pre-decisional administrative
review process intended to reduce litigation.140 HFRA also set forth requirements for judicial
review for HFRA projects.141
134 25 U.S.C. §3103(4)(D); 25 U.S.C. §3104(a).
135 HFRA (16 U.S.C. §§6501 et seq.).
136 16 U.S.C. §6501(1).
137 16 U.S.C. §6511(2); 16 U.S.C. §§6512 et seq.; 16 U.S.C. §§6591 et seq.
138 For the purposes of HFRA, wildland-urban interface (WUI) is defined as an area within or adjacent to an at-risk
community and identified within a plan called a community wildfire protection plan, or, for at-risk communities without
community wildfire protection plans, the WUI includes adjacent lands within specified distances or that meet specified
conditions (16 U.S.C. §6511(16)). HFRA defines at-risk community (16 U.S.C. §6511(1)) as an area composed of
either (1) “an interface community,” as defined in federal regulation (see USDA and DOI, “Wildland Urban Interface
Communities Within the Vicinity of Federal Lands That Are at High Risk from Wildfire,” 66 Federal Register 753,
January 4, 2001), or (2) “a group of homes and other structures with basic infrastructure and services (such as utilities
and collectively maintained transportation routes) within or adjacent to Federal land”; additionally, an at-risk
community has conditions “conducive to a large-scale wildland fire disturbance” and “a significant threat to human life
or property” from wildland fire. As defined in USDA and DOI’s 2001 regulation, an interface community has “a clear
line of demarcation” between the built environment and wildland fuels, “where structures directly abut wildland fuels.”
Other definitions of the WUI may be used in scientific contexts or may apply to other federal statutes, policies, or
programs. WUI is discussed in this report in “Hazardous Fuels and Fire Behavior.” An explanation of fire regimes is in
the section, “Fire Regimes: Fire over Time and Space.”
139 16 U.S.C. §6512.
140 For example, 16 U.S.C. §6513, 16 U.S.C. §6515, 16 U.S.C. §6543.
141 16 U.S.C. §6516.
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In addition, HFRA includes statutory categorical exclusions (CEs), categories of federal actions
that are excluded from the requirement to prepare an environmental impact statement or
environmental assessment under the National Environmental Policy Act (NEPA).142 Several
HFRA CEs are unique to authorized hazardous fuel reduction projects, and others may encompass
a broader suite of hazardous fuel reduction activities.143 HFRA CEs are subject to various
constraints, including project size, and most are available only in specified areas (e.g., designated
areas, areas with specified characteristics).144 Some legislative action in the 119th Congress seeks
to expand the applicability of many HFRA CEs. For example, provisions of the Fix Our Forests
Act (H.R. 471/S. 1462) would expand the applicability of many HFRA CEs.
Collaboration with Nonfederal Groups
Hazardous fuels, and hazardous fuels management issues, cross land ownership and jurisdictional
boundaries. Therefore, managing hazardous fuels often requires collaboration between groups. To
facilitate collaboration across land ownerships, Congress has enacted numerous authorities, most
of which pertain to the FS and BLM. Most such efforts include hazardous fuels management as
one possible application among many. For example, the Collaborative Forest Landscape
Restoration Program and the Joint Chiefs Landscape Restoration Partnership Program provide
dedicated funding for multigroup, cross-boundary landscape management projects for specified
purposes, including hazardous fuel reduction.145 Other authorities facilitate contracting for largescale, long-term projects on federal land or authorize nonfederal partners to conduct work on
federal lands under specified parameters.146 Lastly, some authorities pertain to specific partner
groups; the Tribal Forest Protection Act allows the federal government to enter into agreements or
contracts with Tribes to perform work on certain FS or BLM lands.147
Federal Support for Hazardous Fuels Management on Nonfederal Lands
The federal role in nonfederal hazardous fuels management generally consists of providing
assistance to various nonfederal groups, such as Tribes, states, localities, and private entities,
sometimes operating as collaborative groups. Assistance may consist of financial or technical
support. Federal assistance programs may provide specific project support or overall
programmatic or capacity support (e.g., to ensure baseline levels of capacity or provide broad
142 National Environmental Policy Act (NEPA; 42 U.S.C. §§4321 et seq.). See CRS In Focus IF12560, National
Environmental Policy Act: An Overview, by Kristen Hite and Heather McPherron; and CRS Report R48595,
Legislative Categorical Exclusions Under the National Environmental Policy Act, by Heather McPherron.
143 For a description of legislative categorical exclusions (CEs) in HFRA, see CRS Report R48595, Legislative
Categorical Exclusions Under the National Environmental Policy Act, by Heather McPherron; and CRS Report
R43872, National Forest System Management: Overview and Issues for Congress, by Anne A. Riddle.
144 More information on HFRA and NEPA can be found in CRS Report R43872, National Forest System Management:
Overview and Issues for Congress, by Anne A. Riddle; and CRS In Focus IF12560, National Environmental Policy
Act: An Overview, by Kristen Hite.
145 Collaborative Forest Landscape Restoration Program: 16 U.S.C. §7303; Joint Chiefs Landscape Restoration
Program: 16 U.S.C. §6592d.
146 For more information on assistance programs, the Good Neighbor Authority, and Stewardship End Result
Contracting, see CRS Report R45219, Forest Service Assistance Programs, by Anne A. Riddle; CRS In Focus
IF11658, The Good Neighbor Authority on Federal Lands, by Anne A. Riddle; and CRS In Focus IF11179,
Stewardship End Result Contracting: Forest Service and Bureau of Land Management, by Anne A. Riddle.
147 Tribal Forest Protection Act (25 U.S.C. §§3115a et seq.); FS, “Proposal Evaluation and Determination Factors
Under TFPA,” in Forest Service Handbook 2409.19, p. 37, https://www.fs.usda.gov/about-agency/regulations-policies/
handbook/240919-60-stewardship-contracts-and-agreements. See also CRS Report R48256, Tribal Self-Determination
Authorities: Overview and Issues for Congress, coordinated by Mariel J. Murray; and CRS Report R47563, Tribal Comanagement of Federal Lands: Overview and Selected Issues for Congress, by Mariel J. Murray.
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program support to a state land management agency). Programs can provide financial assistance
through competitive grants, formula grants, or other instruments. No federal program is specific
to hazardous fuel reduction assistance. Such activities may occur through programs related to
broader issues (e.g., forest health, wildfire preparedness, hazard reduction to communities).
Assistance programs reside in various agencies. As examples, several FS assistance programs
provide grants to state governments to promote baseline levels of capacity in areas related to
forest health and wildfire preparedness and response. Other FS grants provide competitive grants
to various groups to manage landscapes at scale, or they provide for community wildfire
defense.148 The Federal Emergency Management Agency (FEMA) provides financial assistance in
certain circumstances for hazardous fuels mitigation near homes and structures.149
Issues for Congress
Authorizations and Programs
Congress debates whether—and, if so, to what extent—to support hazardous fuels mitigation
programs on federal and nonfederal lands. Congress may determine that programs it previously
established are adequate to achieve desired hazardous fuels management goals. Alternatively,
Congress may decide to refine or augment existing or new efforts. For federal lands, this may
involve establishing new authorities or expanding existing authorities. For nonfederal lands, this
may include establishing or modifying assistance programs or supports for nongovernmental
entities that perform work on both federal and nonfederal lands. Congress may choose to
establish programs for specific hazardous fuels mitigation approaches, locations, or situations, or
may set broader goals that allow for substantial local discretion. For a list of legislation
introduced in the 119th Congress that could affect hazardous fuels mitigation policy or
implementation, see Appendix B.
Pace and Scale of Implementation
An issue facing Congress is the pace and scale at which hazardous fuels mitigation occurs.
Congress frequently considers bills that attempt to accelerate the timeline from project conception
to implementation. Associated questions concern how to conduct hazardous fuels mitigation to
protect values at risk from wildfire: whether an adequate number of projects are initiated, at a
suitable size to be effective, in the right locations, using the most appropriate techniques. Two
areas often highlighted in the project context are the availability of qualified personnel and the
effects of environmental and administrative requirements.
Multiple groups have identified shortfalls in the number of qualified personnel available for
planning and conducting hazardous fuels mitigation. The federally mandated Wildland Fire
Mitigation and Management Commission (Wildland Fire Commission) found that “hiring,
recruitment, and retention of the workforce are some of the most significant gaps within the
existing wildfire mitigation and management system.”150 The FS points to investments in
workforce capacity and collaborative partnerships as necessary to achieving the required scale of
148 For more information on FS assistance programs, see CRS Report R45219, Forest Service Assistance Programs, by
Anne A. Riddle.
149 42 U.S.C. §5170c. For more information on FEMA funding for disaster mitigation, see CRS Insight IN11187,
Federal Emergency Management Agency (FEMA) Hazard Mitigation Assistance, by Diane P. Horn; and CRS In Focus
IF12833, Post-Disaster and Pre-Disaster Hazard Mitigation Assistance, by Diane P. Horn.
150 Wildland Fire Commission, “Building a Comprehensive Workforce,” in On Fire, p. 161.
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hazardous fuels mitigation work.151 The Nature Conservancy, a nongovernmental advocacy
organization performing fuel treatments with the agency, points to a lack of trained crews as one
of the top reasons that prescribed burns are not being executed during the short windows of time
when weather is favorable.152
Legislative approaches to workforce shortages may include reforms to federal employment
practices; programs to promote training, workforce development, and housing opportunities; or
authorities to leverage resources across groups by promoting collaboration or easing crossjurisdictional work.153 For example, the National Prescribed Fire Act of 2025 (S. 2015/H.R. 3889)
includes provisions for increased pay for federal employees conducting specified prescribed fire
work. It also would allow specified hazardous fuels appropriations to be used to train federal and
nonfederal groups for prescribed fire, among other purposes. As another example, in May 2025,
the House Committee on Natural Resources held a hearing on a draft bill titled “Fostering
Opportunities to Restore Ecosystems Through Strong Tribal Stewardship Act (FORESTS Act),”
which would expand authority for Tribes to manage specified federal lands, including, but not
limited to, managing hazardous fuels.
The role of environmental and administrative requirements is another common source of debate
when discussing timelines for hazardous fuel reduction on federal lands. Similar to other federal
land management projects, hazardous fuels mitigation projects typically require the agency to
undertake several statutory processes to comply with environmental and administrative
requirements. For example, NEPA delineates the procedure to identify a project’s resource
objectives and analyze effects.154 The National Historic Preservation Act (NHPA) and the
Endangered Species Act (ESA) define additional site-specific analyses and potential consultation
requirements to protect cultural and biological resources.155
Legislative approaches to the role of environmental compliance may include addressing
compliance requirements or litigation under the statute. The Fix Our Forests Act (S. 1462/ H.R.
471) would extend the applicability or acreage of several statutory CEs and reform litigation
related to NEPA for specified projects. The Fix Our Forests Act would authorize the use of
emergency procedures for compliance under NEPA, ESA, and NHPA for projects in certain areas.
Tracking and Accountability
Agency tracking of hazardous fuel reduction accomplishments can sometimes complicate
congressional oversight. For example, the USDA Office of Inspector General (OIG) reported in
151 USDA, FS, Confronting the Wildfire Crisis: A Strategy for Protecting Communities and Improving Resilience in
America’s Forests, FS-1187a, January 2022, pp. 4, 10, 31-35, https://www.fs.usda.gov/sites/default/files/ConfrontingWildfire-Crisis.pdf; USDA, FS, National Active Forest Management Strategy, FS-1268a, May 2025, pp. 3, 6, 10,
https://www.usda.gov/sites/default/files/documents/national-active-forest-management-strategy.pdf; USDA, FS,
National Prescribed Fire Review, September 2022, pp. 16-17, https://www.frames.gov/documents/usfs/USFS_
20220908_National-Prescribed-Fire-Program-Review.pdf.
152 Adiel Kaplan and Monica Hersher, “The Forest Service Is Overstating Its Wildfire Prevention Progress to Congress
Despite Decades of Warnings Not To,” NBC News, August 9, 2022 (hereinafter Kaplan and Hersher, “Forest Service
Overstating Wildfire Prevention Progress”); The Nature Conservancy, https://www.nature.org/en-us/.
153 The Wildland Fire Commission provided legislative recommendations on this topic in the sections “Permitting and
Project Planning” and “Building a Comprehensive Workforce” in On Fire, pp. 78-82, 157-191.
154 42 U.S.C. §§4321 et seq.
155 National Historic Preservation Act (NHPA; 54 U.S.C. §§300101 et seq.), Endangered Species Act (ESA; 16 U.S.C.
§§1531 et seq.). For information on consultation requirements of NHPA and ESA, see CRS Report R47543, Historic
Properties and Federal Responsibilities: An Introduction to Section 106 Reviews, by Mark K. DeSantis; and CRS In
Focus IF12423, Endangered Species Act (ESA) Section 7 Consultation, by Erin H. Ward and Pervaze A. Sheikh.
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2016 that (1) the FS was overstating its accomplishments and (2) the FS had difficulty
determining what it spent on hazardous fuel reduction.156 In 2024, OIG reported that the FS
tracked multiple Infrastructure Investment and Jobs Act (IIJA) provisions in a single budget line
item, so hazardous fuels spending was not available independently of other IIJA provisions.157
The total impact of increased funding from the IIJA on project implementation is therefore
unclear.
Inconsistent agency tracking makes it difficult to determine treatment effects and to compare
different approaches. For example, the FS tracks acres treated for hazardous fuels in its Forest
Service Activity Tracking System (FACTS) database, and the Department of the Interior tracks
hazardous fuels treated in its Interior Fuels and Post-Fire Reporting System (IFPRS).158 When
wildfires burn treated areas, both departments document the interactions between wildfire and
hazardous fuel treatments in the Fuel Treatment Effectiveness Monitoring (FTEM) application.159
If these data were consistently collected and reported, Congress might be able to compare fuel
treatment approaches, to understand cost effectiveness and performance.160
The commonly used acres treated metric to report work completed also might disincentivize
efficient spending on hazardous fuels operations. For example, agencies wishing to show a high
number of acres treated could prioritize projects that cost less per acre, even if the projects are not
located in a strategic area or do not employ the most effective methods.161 The metric is also hard
to interpret, because multiple treatments on the same part of the landscape—which sometimes are
required to measurably decrease fire hazard—may be counted multiple times.162 A related
question is whether agencies should aim for greater risk reduction in smaller areas or a smaller
risk reduction per acre across larger areas.
156 USDA, Office of Inspector General (OIG), Forest Service Wildland Fire Activities: Hazardous Fuels Reduction,
08601-0004-41, July 2016, pp. 13-20, https://www.documentcloud.org/documents/22120891-usda-oig-2016-forestservice-wildland-fire-activities-hazardous-fuels-reduction-08601-0004-41/.
157 USDA, OIG, IIJA: Hazardous Fuels Management, Inspection Report 08801-0001-21, September 2024, pp. 3-4,
https://usdaoig.oversight.gov/sites/default/files/reports/2024-09/08801-0001-21FR508FOIAsigned.pdf.
158 Interagency Standards for Fire and Fire Aviation Operations Group, National Interagency Fire (NIFC), Interagency
Standards for Fire and Fire Aviation Operations ("Red Book”), January 2025, p. 219, https://www.nifc.gov/standards/
guides/red-book (hereinafter NIFC, Red Book). The FS also displays annual acres treated on the U.S. Forest Service
Hazardous Fuels Treatments dashboard, with the caveat, “Accomplishments are defined as treatments that are planned
or contracted to occur. They are not necessarily completed on the ground.” USDA, FS, “U.S. Forest Service Hazardous
Fuels Treatments 2025,” accessed May 10, 2025, https://www.arcgis.com/apps/dashboards/95470eec0ef1424eb1e
74369b3519677.
159 NIFC, Red Book, pp. 219-220; DOI and USDA, IFTDSS, “About FTEM,” accessed May 8, 2025,
https://iftdss.firenet.gov/firenetHelp/help/pageHelp/content/10-ftem/ftemabout.htm?tocpath=FTEM%7C_____1.
160 Government Accountability Office (GAO), Wildland Fire Management: Better Information and a Systematic
Process Could Improve Agencies’ Approach to Allocating Fuel Reduction Funds and Selecting Projects, GAO-071168, September 28, 2007, pp. 44, 57-60, 64-66, https://www.gao.gov/products/gao-07-1168.
161 GAO, Wildland Fire: Federal Agencies’ Efforts to Reduce Wildland Fuels and Lower Risk to Communities and
Ecosystems, GAO-20-52, December 19, 2019, pp. 35-36, https://www.gao.gov/products/gao-20-52; USDA, FS, Fiscal
Year 2025 Budget Justification, March 2024, p. 29a-93, https://www.fs.usda.gov/sites/default/files/fs-fy25congressional-budget-justification.pdf; USDA, FS, Toward Shared Stewardship Across Landscapes: An OutcomeBased Investment Strategy, FS-1118, August 2018, p. 18, https://perma.cc/KJ2Z-CYJ9; Wildland Fire Commission, On
Fire, pp. 17, 252-253; GAO, Forest Service: Fully Following Leading Practices for Agency Reforms Would Strengthen
Prescribed Fire Program, GAO-24-106239, June 2024, pp. 33-34, https://www.gao.gov/assets/gao-24-106239.pdf
(hereinafter GAO, Reforms Would Strengthen Prescribed Fire Program, GAO-24-106239); Scott Rodd, “Stalled U.S.
Forest Service Project Could Have Protected California Town from Caldor Fire Destruction,” CAPRadio, August 16,
2022.
162 Kaplan and Hersher, “Forest Service Overstating Wildfire Prevention Progress”; George LeVines and Emily
Zentner, “How We Measured U.S. Forest Service Wildfire Prevention Work,” CAPRadio, August 16, 2022.
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The FS, Government Accountability Office, and the Wildland Fire Commission all recommend
improving performance metrics for hazardous fuels mitigation, including prescribed fire.163 Bills
in the 119th Congress, including the ACRES Act (H.R. 204) and the Fix Our Forests Act, include
reporting requirements such as accurate size of area treated, treatment costs, location with regard
to WUI and wildfire risk, and type of treatment activity (see Table B-1).164
163 GAO, Reforms Would Strengthen Prescribed Fire Program, GAO-24-106239, pp. 33-34; USDA, FS, National
Prescribed Fire Program Review, pp. 9, 12, and Appendix A p. 23; The Wildland Fire Commission’s
recommendations regarding performance measures include Recommendations 13, 32, and 123, as well as the section
entitled, “Accountability”; see Wildland Fire Commission, On Fire, pp. 17, 60-61, 80-81, 220-221, 252-254.
164 Fix Our Forests Act (S. 1462, §302; H.R. 471, §302); ACRES Act (H.R. 204).
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Appendix A. Fire Regime Classifications
The following tables provide Forest Service (FS) descriptions and definitions codified in the
Healthy Forests Restoration Act (HFRA) for fire regimes (Table A-1) and condition classes
(Table A-2).165 The FS described five “historical natural fire regimes” and three “fire regime
current condition classes.” HFRA codified three of the five fire regimes and two of the three
condition classes for the purposes of the act. The statutory definitions are not broadly applicable.
Table A-1 and Table A-2 provide the FS descriptions and statutory definitions for fire regimes
and condition classes.
Table A-1. Fire Regime Classifications
Forest Service: “Historical Natural
Fire Regimes”
Code
Description
Statutory Definitions
I
“0–35-year frequency,[a] low
severity[b]”
Fire Regime I
The term “fire regime I” means an area(A) in which historically there have been low-severity fires with a
frequency of 0 through 35 years; and
(B) that is located primarily in low elevation forests of pine, oak, or
pinyon juniper.
II
“0–35-year frequency, standreplacement severity”
Fire Regime II
The term “fire regime II” means an area(A) in which historically there are stand replacement severity fires with
a frequency of 0 through 35 years; and
(B) that is located primarily in low- to mid-elevation rangeland,
grassland, or shrubland.
III
“35–100+ year frequency,
mixed severity”
Fire Regime III
The term “fire regime III” means an area(A) in which historically there are mixed severity fires with a frequency
of 35 through 100 years; and
(B) that is located primarily in forests of mixed conifer, dry Douglas fir,
or wet Ponderosa pine.
IV
“35–100+ year frequency,
stand-replacement severity”
Not defined in statute.
V
“200+ year frequency, standreplacement severity”
Not defined in statute.
Sources: Forest Service descriptions are taken from Table 1 in Kirsten M. Schmidt et al., Development of CoarseScale Spatial Data for Wildland Fire and Fuel Management, U.S. Department of Agriculture, Forest Service, RMRSGTR-87, p. 5, https://www.fs.usda.gov/rm/pubs/rmrs_gtr087.pdf (hereinafter Schmidt et al., Coarse-Scale Spatial
Data for Fuel Management). Statutory definitions are taken from 16 U.S.C. §6511 (8-10).
Notes:
a. Fire frequency is defined in Schmidt et al., Coarse-Scale Spatial Data for Fuel Management, and also commonly
understood as “the average number of years between fires.”
165 HFRA (16 U.S.C. §§6501 et seq.).
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b.
Severity is defined in Schmidt et al., Coarse-Scale Spatial Data for Fuel Management, as “the effect of the fire on
the dominant overstory vegetation.” This FS definition of severity differs from the definition of severity used
elsewhere in this report, which includes a broader suite of potential effects (e.g., to soils).
Table A-2. Fire Regime Condition Class
Forest Service: “Fire Regime Current Condition Class[a]”
Condition
Class
Fire Regime
Example Management
Options
Statutory Definitions
1
“Fire regimes are within an
historical range and the
risk of losing key
ecosystem components is
low. Vegetation attributes
(species composition and
structure) are intact and
functioning within an
historical range.”
“Where appropriate, these
areas can be maintained within
the historical fire regime by
treatments such as fire use.”
Not defined in statute.
2
“Fire regimes have been
moderately altered from
their historical range. The
risk of losing key
ecosystem components is
moderate. Fire frequencies
have departed from
historical frequencies by
one or more return
intervals (either increased
or decreased). This results
in moderate changes to
one or more of the
following: fire size,
intensity and severity, and
landscape patterns.
Vegetation attributes have
been moderately altered
from their historical
range.”
“Where appropriate, these
areas may need moderate
levels of restoration
treatments, such as fire use and
hand or mechanical treatments,
to be restored to the historical
fire regime.”
Condition Class 2
The term “condition class 2”, with
respect to an area of Federal land,
means the condition class
description developed by the Forest
Service Rocky Mountain Research
Station in the general technical
report entitled “Development of
Coarse-Scale Spatial Data for
Wildland Fire and Fuel
Management” (RMRS–87), dated
April 2000 (including any
subsequent revision to the report),
under which—
(A) fire regimes on the land have
been moderately altered from
historical ranges;
(B) there exists a moderate risk of
losing key ecosystem components
from fire;
(C) fire frequencies have increased
or decreased from historical
frequencies by 1 or more return
intervals, resulting in moderate
changes to(i) the size, frequency, intensity, or
severity of fires; or
(ii) landscape patterns; and
(D) vegetation attributes have been
moderately altered from the
historical range of the attributes.
(16 U.S.C. §6511(4))
3
“Fire regimes have been
significantly altered from
their historical range. The
risk of losing key
ecosystem components is
“Where appropriate, these
areas may need high levels of
restoration treatments, such as
hand or mechanical treatments,
before fire can be used to
Condition Class 3
The term “condition class 3”, with
respect to an area of Federal land,
means the condition class
description developed by the Rocky
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Forest Service: “Fire Regime Current Condition Class[a]”
Condition
Class
Fire Regime
high. Fire frequencies have
departed from historical
frequencies by multiple
return intervals. This
results in dramatic changes
to one or more of the
following: fire size,
intensity, severity, and
landscape patterns.
Vegetation attributes have
been significantly altered
from their historical
range.”
Example Management
Options
restore the historical fire
regime.”
Statutory Definitions
Mountain Research Station in the
general technical report referred to
in paragraph (4) (including any
subsequent revision to the report),
under which—
(A) fire regimes on land have been
significantly altered from historical
ranges;
(B) there exists a high risk of losing
key ecosystem components from
fire;
(C) fire frequencies have departed
from historical frequencies by
multiple return intervals, resulting in
dramatic changes to(i) the size, frequency, intensity, or
severity of fires; or
(ii) landscape patterns; and
(D) vegetation attributes have been
significantly altered from the
historical range of the attributes.
(16 U.S.C. §6511(5))
Sources: Forest Service (FS) descriptions are taken from Table 2 in Kirsten M. Schmidt et al., Development of
Coarse-Scale Spatial Data for Wildland Fire and Fuel Management, U.S. Department of Agriculture, Forest Service,
RMRS-GTR-87, p. 8, https://www.fs.usda.gov/rm/pubs/rmrs_gtr087.pdf (hereinafter Schmidt et al., Coarse-Scale
Spatial Data for Fuel Management). Statutory definitions are taken from 16 U.S.C. §6511(4-5).
Notes:
a. Fire regime current condition classes are defined in Schmidt et al., Coarse-Scale Spatial Data for Fuel Management,
as “a qualitative measure describing the degree of departure from historical fire regimes, possibly resulting
in alterations of key ecosystem components such as species composition, structural stage, stand age, canopy
closure, and fuel loadings. One or more of the following activities may have caused this departure: fire
suppression, timber harvesting, livestock grazing, introduction and establishment of exotic plant species,
introduced insects or disease, or other management activities.”
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Appendix B. Hazardous Fuels Mitigation
Introduced Legislation in the 119th Congress
Table B-1 lists legislation introduced in the 119th Congress that may affect hazardous fuels
mitigation policy or implementation. Entries are current as of September 2, 2025.
Table B-1. Hazardous Fuels Mitigation Bills in the 119th Congress
Bill
Number
Title
Description
S. 91
Western Wildfire Support Act of
2025
To improve federal activities relating to wildfires, and for
other purposes.
S. 135
Wildland Firefighter Paycheck
Protection Act of 2025
A bill to amend Title 5, United States Code, to provide for
special base rates of pay for wildland firefighters, and for
other purposes.
S. 140
Wildfire Prevention Act of 2025
To address the forest health crisis on the National Forest
System and public lands, and for other purposes.
S. 279
Tim Hart Wildland Firefighter
Classification and Pay Parity Act (Tim’s
Act)
A bill to reform and enhance the pay and benefits of federal
wildland firefighters, and for other purposes.
S. 349
Fire-Safe Electrical Corridors Act of
2025
To authorize the Secretary of Agriculture to permit
removal of trees around electrical lines on National Forest
System land without conducting a timber sale, and for
other purposes.
S. 350
Wildfire Emergency Act of 2025
To direct the Secretary of Agriculture to select and
implement landscape-scale forest restoration projects to
assist communities in increasing their resilience to wildfire,
and for other purposes.
S. 395
Emergency Fuel Reduction Act of
2025
To amend the Healthy Forests Restoration Act of 2003 to
expedite wildfire prevention projects to reduce the risk of
wildfire on certain high-risk federal land, and for other
purposes.
S. 449
Expediting Forest Restoration and
Recovery Act of 2025
To amend the Healthy Forests Restoration Act of 2003 to
require the Secretary of Agriculture to expedite hazardous
fuel or insect and disease risk reduction projects on certain
National Forest System land, and for other purposes.
S. 453
Wildfire Intelligence Collaboration and
Coordination Act of 2025
To establish a Wildfire Intelligence Center, and for other
purposes.
S. 602
Wildfire Resilience Through Grazing
Research Act
To amend the Food, Agriculture, Conservation, and Trade
Act of 1990 to support research and development of
ungulate grazing land management techniques for purposes
of wildfire mitigation, fuel reduction, and postfire recovery.
S. 647
Regional Leadership in Wildland Fire
Research Act of 2025
To require the Secretary of Commerce to create regional
wildland fire research centers, and for other purposes.
S. 670
Protect the West Act of 2025
To establish an Outdoor Restoration Fund for restoration
and resilience projects, and for other purposes.
S. 1323
The Facilitating Increased Resilience,
Environmental Weatherization and
Lowered Liability (FIREWALL) Act
To amend the Internal Revenue Code of 1986 to provide a
refundable credit against tax for disaster mitigation
expenditures.
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Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
Bill
Number
Title
Description
S. 1462
Fix Our Forests Act
To improve forest management activities on National
Forest System land, public land under the jurisdiction of the
Bureau of Land Management, and tribal land to return
resilience to overgrown, fire-prone forested land, and for
other purposes.
S. 1842
Wildfire Reduction and Carbon
Removal Act of 2025
To amend the Internal Revenue Code of 1986 to create a
credit for carbon removal and storage for forest residues
from wildfire management.
S. 2015
National Prescribed Fire Act of 2025
To direct the Secretary of the Interior and the Secretary of
Agriculture to encourage and expand the use of prescribed
fire on land managed by the Department of the Interior or
the Forest Service, with an emphasis on units of the
National Forest System in the western and southeastern
United States, to acknowledge and support the longstanding use of cultural burning by Indian Tribes and
Indigenous practitioners, and for other purposes.
S. 2038
Wildfire Coordination Act
To direct the Secretary of the Interior to establish the
Wildfire Science and Technology Advisory Board.
S. 2208
Wildfire Resilient Communities Act
To provide mandatory funding for hazardous fuels
reduction projects on certain federal land, and for other
purposes.
S. 2431
Department of the Interior,
Environment, and Related Agencies
Appropriations Act, 2026
Making appropriations for the Department of the Interior,
environment, and related agencies for the fiscal year ending
September 30, 2026, and for other purposes.
H.R. 168
TORCH Act
To improve the ability of the Secretary of Agriculture and
the Secretary of the Interior to carry out forest
management activities that reduce the risk of catastrophic
wildfires, and for other purposes.
H.R. 178
To require the Secretary of
Agriculture to Carry Out Activities to
Suppress Wildfires, and for Other
Purposes
To require the Secretary of Agriculture to carry out
activities to suppress wildfires, and for other purposes.
H.R. 179
Proven Forest Management Act of
2025
To direct the Secretary concerned to coordinate with
impacted parties when conducting a forest management
activity, and for other purposes.
H.R. 184
Action Versus No Action Act
To require that only two alternatives be considered with
respect to certain proposed collaborative forest
management activities, and for other purposes.
H.R. 191
Inflation Reduction Act of 2025
To repeal the Inflation Reduction Act of 2022.
H.R. 204
ACRES Act
To require that the Secretary of Agriculture and the
Secretary of the Interior submit accurate reports regarding
hazardous fuels reduction activities, and for other
purposes.
H.R. 471
Fix Our Forests Act
To expedite under the National Environmental Policy Act
of 1969 and improve forest management activities on
National Forest System lands, on public lands under the
jurisdiction of the Bureau of Land Management, and on
tribal lands to return resilience to overgrown, fire-prone
forested lands, and for other purposes.
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Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
Bill
Number
Title
Description
H.R. 527
Strengthening Wildfire Resiliency
Through Satellites Act of 2025
To direct the Secretary of the Interior, acting through the
Director of the United States Geological Survey, to
establish a grant program for monitoring wildfires by
satellite.
H.R. 582
Community Protection and Wildfire
Resilience Act
To establish a community protection and wildfire resilience
grant program, and for other purposes.
H.R. 731
Green Tape Elimination Act of 2025
To exempt hazardous fuel reduction activities from certain
environmental requirements for a 10-year period.
H.R. 743
Tim Hart Wildland Firefighter
Classification and Pay Parity Act (Tim’s
Act)
To reform and enhance the pay and benefits of federal
wildland firefighters, and for other purposes.
H.R. 948
Safe HOME Act
To amend the Internal Revenue Code of 1986 to provide a
refundable credit against tax for wildfire mitigation
expenditures.
H.R. 1105
Disaster Resiliency and Coverage Act
of 2025
To amend the Robert T. Stafford Disaster Relief and
Emergency Assistance Act to require the President to
establish an individual household disaster mitigation
program, and for other purposes.
H.R. 1110
Grazing for Wildfire Risk Reduction
Act
To require the Secretary of Agriculture to develop and
implement a strategy to increase opportunities to utilize
livestock grazing as a means of wildfire risk reduction.
H.R. 1393
Wildfire Response Improvement Act
To direct the Administrator of the Federal Emergency
Management Agency to conduct a review of the criteria for
evaluating the cost-effectiveness of certain mitigation
projects, and for other purposes.
H.R. 1459
Protect the West Act of 2025
To establish an Outdoor Restoration Fund for restoration
and resilience projects, and for other purposes.
H.R. 1820
FLASH Act
To address the public safety issues and environmental
destruction currently impacting federal lands along the
southern border, enhance border security through the
construction of navigable roads on federal lands along the
southern border, provide U.S. Customs and Border
Protection access to federal lands to improve the safety
and effectiveness of enforcement activities, allow states to
place temporary barriers on federal land to secure the
southern border, reduce the massive trash accumulations
and environmental degradation along the southern border,
reduce the cultivation of illegal cannabis on federal lands,
mitigate wildland fires caused by illegal immigration, and
prohibit migrant housing on federal lands.
H.R. 1923
Modernizing Wildfire Safety and
Prevention Act of 2024
To provide for the implementation of certain
recommendations from the Report of the Wildland Fire
Mitigation and Management Commission.
H.R. 2026
Ending Major Borderland
Environmental Ruin from Wildfires
(EMBER) Act
To mitigate environmental degradation and wildland fires
caused by illegal immigration along the southern border of
the United States, and for other purposes.
H.R. 2492
Fire Safe Electrical Corridors Act of
2025
To authorize the Secretary of Agriculture and the
Secretary of the Interior to permit removal of trees around
electrical lines on National Forest System lands and Bureau
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Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
Bill
Number
Title
Description
of Land Management lands, respectively, without
conducting a timber sale, and for other purposes.
H.R. 2709
Save Our Sequoias Act
To improve the health and resiliency of giant sequoias, and
for other purposes.
H.R. 3553
BRUSH Fires Act
To direct the Secretary of Agriculture to carry out a study
with respect to the effectiveness of available wildfire
mitigation methods in reducing the risk of wildfire and the
severity of damages from wildfire in communities within or
adjacent to shrubland ecosystems, and for other purposes.
H.R. 3637
Locally Led Restoration Act of 2025
To amend the Healthy Forests Restoration Act of 2003
with respect to third-party contracts for wildfire hazard
fuel removal, to amend the National Forest Management
Act with respect to the threshold for advertised timber
sales, and for other purposes.
H.R. 3889
National Prescribed Fire Act of 2025
To direct the Secretary of the Interior and the Secretary of
Agriculture to encourage and expand the use of prescribed
fire on land managed by the Department of the Interior or
the Forest Service, with an emphasis on units of the
National Forest System in the western and southeastern
United States, to acknowledge and support the longstanding use of cultural burning by Indian Tribes and
Indigenous practitioners, and for other purposes.
H.R. 3923
Wildfire Coordination Act
To direct the Secretary of the Interior to establish the
Wildfire Science and Technology Advisory Board, and for
other purposes.
H.R. 4075
Fire Weather Development Act of
2025
To direct the Administrator of the National Oceanic and
Atmospheric [Administration] to improve fire weather and
fire environment forecasting, detection, and local
collaboration, and for other purposes.
H.R. 4181
WILTR Act of 2025, Wildfire
Infrastructure and Landowner Tax
Relief Act of 2025
To amend the Internal Revenue Code of 1986 to provide
incentives for wildfire prevention.
H.R. 4218
CLEAR Act (Clean Air and Economic
Advancement Reform Act)
To amend the Clean Air Act to facilitate state
implementation of national ambient air quality standards,
and for other purposes.
H.R. 4295
Wildfire Resilient Communities Act
To provide mandatory funding for hazardous fuels
reduction projects on certain federal land, and for other
purposes.
H.R. 4754
Department of the Interior,
Environment, and Related Agencies
Appropriations Act, 2026
Making appropriations for the Department of the Interior,
environment, and related agencies for the fiscal year ending
September 30, 2026, and for other purposes.
Sources: Bill titles and descriptions at Congress.gov, https://www.congress.gov/.
Congressional Research Service
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Hazardous Fuels and Wildfire Mitigation: Background and Congressional Considerations
Author Information
Alicyn R. Gitlin
Analyst in Natural Resources Policy
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Congressional Research Service
R48779 · VERSION 4 · UPDATED
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