Laguna Niguel City Council
June 9, 2026

CITY OF LAGUNA NIGUEL

CITY COUNCIL AGENDA ITEM
To:

FROM:

DATE:

SUBJECT:

Honorable Mayor and Council Members
Tamara S. Letourneau, City Manager
June 9, 2026
Defensible Space and Vegetation Management Program Effectiveness Report

RECOMMENDATION
Staff recommends that the City Council receive and file the Defensible Space and Vegetation Management Program Effectiveness Report.

BACKGROUND
Southern California experiences wildfires that are destructive and hard to contain due to a combination of fuels, terrain, and weather. These wildfires can be particularly destructive when they occur in the Wildland Urban Interface (WUI), the area where development, including structures and other infrastructure, meets or intermixes with undeveloped wildlands. The City is located within the WUI with wildland areas intermixed throughout the City and surrounding the City.

The City is responsible for ensuring compliance with vegetation management on City property, including open spaces. The City currently manages vegetation within 11 weed abatement areas totaling approximately 44 acres on City-owned open space. All weed abatement areas are near homes and other structures on properties adjacent to City­ owned open space. This is because the defensible space and vegetation management program is intended to reduce wildfire risk to nearby structures. The weed abatement program primarily addresses annual grasslands and is designed to meet OCFA defensible space and vegetation management guidance within the 100-foot zone where structures are at risk. In compliance with OCFA requirements, the City has already completed its required weed abatement for the year.

During the June 9, 2025, City Council meeting, the City Council instructed staff to issue a Request for Proposal (RFP) to conduct a Defensible Space and Vegetation Management Study to evaluate the City's vegetation management program. Following the issuance of the RFP, the City Council awarded the professional services agreement for the Defensible Space and Vegetation Management Study to Dudek on October 21 , 2025.

ANALYSIS
The Defensible Space and Vegetation Management Program Effectiveness Report assesses the effectiveness of the current Defensible Space and Vegetation Management Program on City-owned open space, with the goal of reducing wildfire risk in the community (Attachment A). Specifically, the goals of the assessment were as follows:

I. Conduct a comprehensive vegetation management analysis of City-owned open space.

II. Identify (if applicable) priority parcels for additional weed abatement activities and a narrative discussing prioritization rationale, to include benefits and constraints.

Ill. Prepare maps of all City-owned open spaces with applicable recommendations illustrating the results of the study (if applicable).

IV. Develop GIS-based tools to prioritize parcels as necessary.

The report summarizes the assessment results and includes maps, tables, and a narrative describing the vegetation characteristics and topography of the fire environment on City-owned open space and surrounding areas. The report includes, where appropriate, recommendations to modify the existing vegetation management program to improve wildfire safety. These recommendations include feasibility, constraints, environmental compliance, and effectiveness in modifying the existing vegetation management program.

Report Findings
The report findings conclude that the City is meeting both State and local defensible space requirements for City-owned open space. Further, the City's maintenance practices align with OCFA standards (e.g., grass height reduction, shrub spacing and height limits, removal of dead vegetation). Additional key findings include:
• Wildfire behavior modeling indicates that, in the predominant fuels present within the weed abatement areas (annual grass and herbaceous plant cover), a managed zone consistent with the 100-foot defensible space concept is sufficient to meaningfully reduce flame lengths and fire intensity near structures during both typical fire-season and extreme weather scenarios.
• Vegetation Management Program effectiveness is influenced by the continuity (anchoring) of treated areas and conditions on adjacent non-City land. Several treatment areas end at property boundaries without a non-burnable anchor or adjacent treatment continuity, allowing wildfire to potentially move around treated areas.
• A limited area of City-owned open space in the Salt Creek Corridor is within 100 feet of structures but is not currently included in the City's weed abatement program.

• The City has an opportunity to increase wildfire prevention awareness by modifying weed abatement strategies in a target area of the City's existing weed abatement program.

Report Recommendations
Based on Dudek's thorough analysis and findings presented in the report, the following four recommendations were made.

Category Recommendation

1. While not mandated by state law nor local regulations, Dudek recommends adding the Southwest corner of Salt
Creek Corridor near Niguel Road to the City's weed
Weed Abatement abatement program (Opportunity Area A).

2. Modify the weed abatement strategy used in weed
abatement area #6 (Reef View Node: 2.6 acres) from hand crews to goat grazing to increase community awareness on wildfire prevention and weed abatement strategies.

3. Coordinate vegetation management timing, access, and Vegetation standards with adjacent HOAs, homeowners, and other Management agencies to ensure the full defensible space area is maintained.

4. File a CEQA Notice of Exemption (NOE) for implementation CEQA of best management practices (BMPs) for biological resources, cultural resources, hydrology/water quality, and soils.

Following completion of the report, staff, in partnership with OCFA, reviewed the report and initiated proactive measures to address each recommendation. Actions taken to address each recommendation listed in the report include:
• Recommendation 1: In conjunction with OCFA, staff have engaged in discussions with the respective Homeowners Association within Opportunity Area A to facilitate the implementation of additional weed abatement activities, both on private property and City-owned open space. Weed abatement in this area will be completed in accordance with OCFA requirements and best practices. • Recommendation 2: Staff is currently in the process of securing goats for the implementation of next year's weed abatement program, as weed abatement activities at Reef View Node have been completed for the current year. In advance of the anticipated deployment, the City will conduct outreach to promote the goat grazing program through its website and social media platforms to enhance public awareness and engagement.

• Recommendation 3: The City will continue to coordinate vegetation management with HOAs, homeowners, and other agencies to ensure the maintenance of defensible space. As indicated in the report, the City maintains an active and ongoing role in this area and will continue to collaborate with HOAs to implement and sustain effective vegetation management practices.
• Recommendation 4: Staff, in coordination with the City Attorney's Office, will file a Notice of Exemption for the City's weed abatement activities and will continue to do so, as appropriate, for future weed abatement efforts.

The report shows that the City is doing an excellent job of managing City-owned open space and maintaining these areas to meet both State and local regulations. Further implementation of the recommendations in this study will continue to enhance the City's existing fire protection programs and protections for the community, while maintaining the City's high-quality open spaces. Staff recommends that the City Council receive and file the Defensible Space and Vegetation Management Program Effectiveness Report. This Report supports Goal 3: Open Space and Environmental Preservation in the City's adopted Strategic Plan.

FISCAL REVIEW
There is no fiscal impact as a result of this report.

LEGAL REVIEW
No legal review is required for this report.

CONCLUSION
Staff recommends that the City Council receive and file the Defensible Space and Vegetation Management Program Effectiveness Report.
~ ~c(}p~ Tamara S. Letourneau
City Manager
~ X. 0~ Kevin X. O'Connor
Assistant to the City Manager
Scott Frame
Parks and Landscape Maintenance
Superintendent
Attachment:

A. Defensible Space and Vegetation Management Program Effectiveness Report

ATTACHMENT A Defensible Space and Vegetation Management Program Effectiveness Report

City of Laguna Niguel
Defensible Space and
Vegetation Management
Program Effectiveness
JUNE 2026
Prepared for:

CITY OF LAGUNA NIGUEL
30111 Crown Valley Parkway
Laguna Niguel, California 92677
Prepared by:

DUDEK
687 S. Coast Highway 101, Suite 110
Encinitas, California 92024
Jeremy Cawn
Fire Prevention Planner
DUDEK.COM

Table of Contents
SECTION PAGE NO.

Executive Summary 1
Background 3
City of Laguna Niguel Open Space 3
OCFA Standards 9
Local and State Fire Codes 10
Analysis and Recommendations 13
Wildfire Risk Assessment & Modeling Results 13
Wildfire Hazard Modeling Results 17
Vegetation Management Program Analysis 20
CEQA Analysis 24
Findings and Recommendations 26
Conclusion 31
References 33
TABLES
1 Open Space Landownership in Laguna Niguel 8
2 Existing Weed Abatement Areas 12
3 Flame Length and Suppression Efforts 14

EXHIBITS
1 Fire Observation/ Description 15
2 Relative Wildfire Hazard Classification Matrix 17

APPENDICES
A Acronyms and Abbreviations
B List of Key Terms with Definitions
C Assessment Methodology
D Figures
E Graphs
F OCFA C-05 Fuel Modification Guidelines
G Additional Tables

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Executive Summary
Southern California experiences destructive, hard-to-contain wildfires due to a combination of fuels, terrain, and weather. These wildfires can be particularly destructive when they occur in the Wildland Urban Interface (WUl),1 the area where development, including structures and other infrastructure, meets or intermixes with undeveloped wildlands (NIST, 2025).

The City of Laguna Niguel is in the WUI with wild land areas intermixed throughout the City and surrounding the City.

As such, the City has experienced several fires over the years, including the 2022 Coastal Fire.

Current Vegetation Management Area & Approach
The City currently manages vegetation within 11 weed abatement areas totaling approximately 44 acres on City­ owned open space. All weed abatement areas are near homes and other structures on properties adjacent to City­ owned open space because the defensible space2 and vegetation management program is intended to reduce wildfire risk to nearby structures. The weed abatement program primarily addresses annual grasslands and is designed to meet OCFA defensible space and vegetation management guidance within the 100-foot zone where structures are at risk.

Study Purpose & Methodology
The City contracted with Dudek to assess the effectiveness of the current Defensible Space and Vegetation Management Program on City-owned open space (Project Area), with the goal of reducing wildfire risk in the community. Specifically, the goals of the assessment were as follows:

I. Conduct a comprehensive vegetation management analysis of City-owned open space.

II. Identify (if applicable) priority parcels for additional weed abatement activities and a narrative discussing prioritization rationale, to include benefits and constraints.

Ill. Prepare maps of all City-owned open spaces with applicable recommendations illustrating the results of the study (if applicable).

IV. Develop GIS-based tools to prioritize parcels as necessary.

Dudek fire-prevention planners completed the study and prepared this report, which summarizes the assessment results and includes maps, tables, and a narrative describing the vegetation characteristics and topography of the fire environment on City-owned open space and surrounding areas. This report includes, where appropriate, recommendations to modify the existing vegetation management program to improve wildfire safety. These recommendations include feasibility, constraints, environmental compliance, and effectiveness in modifying the existing vegetation management program. The specific methodology used in this analysis is shown in Appendix C.

Key Findings
Overall, the City is meeting both State and local defensible space requirements for City-owned open space. The City's vegetation maintenance practices align with OCFA standards for treatment standards (e.g., grass height 1 See Appendix A for a table of acronyms/abbreviations and their definitions. 2 A list of key terms with definitions is included as Appendix 8.

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reduction, shrub spacing and height limits, removal of dead vegetation) and the areas that need to be treated.

Below are some additional key findings:
• Wildfire behavior modeling indicates that, in the predominant fuels present within the weed abatement areas (annual grass and herbaceous plant cover), a managed zone consistent with the 100-foot defensible space concept is more than suff icient to reduce flame lengths and fire intensity near structures during both typical fire-season and extreme weather scenarios.
• Vegetation Management Program eff ectiveness is influenced by the continuity (anchoring) of treated areas and conditions on adjacent non-City land. Several treatment areas terminate at property boundaries without a non-burnable anchor or adjacent treatment continuity, allowing wildfire to potentially spread around treated areas.
• A limited area of City-owned open space in the Salt Creek Corridor is within 100 feet of structures but is not currently included in the City's weed abatement program. • The City has an opportunity to increase wildfire prevention awareness by modifying weed abatement strategies in a target area (Reef View Node) of the City's existing weed abatement program.

Recommendations
Based upon a thorough analysis, Dudek makes the following four recommendations to the City of Laguna Niguel:

Category I Recommendation
Weed Abatement 1) Dudek recommends adding the Southwest corner of Salt Creek Corridor near Niguel Road to the City's weed abatement program (Opportunity Area A). 2) Modify the weed abatement strategy used in weed abatement area #6 (Reef View Node: 2.6 acres) from hand crews to goat grazing to increase community awareness on wildfire prevention and weed abatement strategies.

Vegetation Management 3) Coordinate vegetation management timing, access, and standards with adjacent HOAs, homeowners, and other agencies to ensure the full defensible space area is maintained.

CEQA 4) File a CEQA Notice of Exemption (NOE) for implementation of best management practices (BMPs) for biological resources, cultural resources, hydrology/ water quality, and soils.

Conclusion
The City of Laguna Niguel's current weed abatement program creates effective barriers to the spread of a high­ intensity wildfire through the maintenance of hillside vegetation near the communities and homes adjacent to City­ owned open space. Further implementation of the recommendations in this study will continue to enhance the City's existing fire protection programs and protections for the community, while maintaining the City's high-quality open spaces.

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Background
City of Laguna Niguel Open Space
Laguna Niguel is located in southern Orange County in Southern California, approximately midway between Los Angeles and San Diego. Laguna Niguel covers a total area of 14.8 square miles. The City lies within the San Joaquin Hills, approximately 5 miles inland from the Pacific Ocean, and is bordered by Aliso Viejo to the north, Mission Viejo to the northeast, Dana Point to the south, and Laguna Beach to the west. This location places Laguna Niguel within the coastal-influenced portion of Orange County, where marine air and moderate temperatures shape local climatic conditions.

Development within Laguna Niguel consists largely of planned residential neighborhoods integrated with parks, open space, and recreational areas. One of the City's primary open spaces and recreational features is the County of Orange Laguna Niguel Regional Park, which includes a reservoir, trails, and surrounding natural areas. The City's topography and proximity to coastal natural areas contribute to a mix of developed land and preserved open space throughout the community.

The City of Laguna Niguel manages a variety of open space areas located at the interface between residential neighborhoods and fire-adapted coastal foothill ecosystems, which incorporate the repeated occurrence of fire as an integral process (Sugihara et al., 2006). Fire has been a continuous natural disturbance in this area since at least the last ice age, and native species have evolved and adapted with wildfire. These lands exist within a broader environment characterized by steep terrain, dense, continuous vegetation, and weather conditions conducive to rapid fire spread. As fire season becomes longer each year, the City faces increasing exposure to ignition, fast-moving fires, and potential structure loss, particularly where open space directly borders homes.

City-owned open spaces include fuel conditions and topographic features that can generate flame lengths and fire intensities beyond what is addressed by the state's minimum 100-foot defensible-space requirement. While defensible space provides an important initial buffer, many open-space parcels extend upslope, downslope, or laterally beyond this distance, creating additional zones where wildfire can influence adjacent development. Figure 1 (all figures can be found in Appendix D) shows the location of City-owned open space areas throughout Laguna Niguel.

Since fuels (vegetation) are the only element of the fire environment that can be directly managed, this study is intended to help City officials determine where vegetation treatments will be most effective, where current practices leave gaps, and where physical constraints such as steep slopes or landslide-prone areas may limit treatment options.

Terrain
The terrain within Laguna Niguel is characterized by rolling hills, ridgelines, and canyon systems that form part of the coastal foothill landscape of southern Orange County. These landforms create a visually diverse environment.

Consisting of developed residential areas interspersed with preserved open space, parks, and natural habitat corridors. The City's terrain includes prominent hillsides and elevated viewpoints that provide expansive views of surrounding canyons, open space corridors, and distant regional landmarks. From higher elevations within the City, DUDEK 3
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views extend toward the nearby Pacific Ocean as well as inland toward the Santa Ana Mountains (City of Laguna Niguel 2025).

A defining feature of the City's landscape is its extensive network of open space areas and natural corridors located along hillsides and canyon systems. Several regional open space areas occur within or border the City, including Aliso and Wood Canyons Wilderness Park, Laguna Niguel Regional Park, and Salt Creek Corridor Regional Park. These open spaces preserve natural landfo rms, provide wildlife habitat, and maintain scenic ridgelines that contribute to the City's overall visual character (City of Laguna Niguel 2025).

The terrain throughout Laguna Niguel includes a combination of hillside slopes, canyon bottoms, and ridgelines that influence drainage patt erns and ecological connectivity. Natural corridors such as the Aliso Creek and the Salt Creek drainage system shape the surrounding terrain and contribute to the formation of canyon features across the area.

These topographic features create localized variations in slope, aspect, and wind exposure that influence vegetation patt erns and habitat connectivity throughout the landscape (City of Laguna Niguel 2025).

Terrain plays an important role in influencing wildfire movement and spread within the City's open space areas. Flat or gently sloping areas may result in slower fire spread under moderate weather conditions; however, steeper slopes and canyon alignments can accelerate fire movement. Topographic features such as saddles, canyons, and ridgelines can create localized wind patt erns that funnel or concentrate airflow, increasing fire spread rates and influencing fire direction. Steep terrain can contribute to faster upslope fire spread due to the preheating and drying of vegetation located above the flame front. Conversely, certain terrain features may buff er or redirect winds depending on the orientation of slopes and canyon formations. Saddles and ridgeline connections between adjacent drainages may also facilitate wildfire movement from one canyon system to another. Various terrain features can therefore influence wildfire behavior across the landscape, as summarized below: Effects ofT opographic Features on Fire Behavior. (Teie 1994; NFPA 2011 )
• Ridge - Fires may change direction when reaching the ridge/ canyon edge; strong airflows are likely at the ridge point; there is a possibility for different wind directions on different sides of the ridge. Ridges experience more wind. Fires gain speed and intensity, moving toward a ridge. Fires burning at a ridge can exhibit erratic behavior. Strong air flows can cause fire to whirl. Wind crossing a ridge usually has a leeward eddy where the wind rolls around and comes up the leeward side. • Saddle- Potential for rapid rates of fire spread; fires pushed through saddles faster during upslope runs.

Winds can increase when blowing through saddles due to the funneling effect of the constricted pass. On the other side, winds will slow, but erratic winds potentially occur at the saddle due to eddies. • Narrow Canyon- Surface winds follow canyon direction, which may differ from the prevailing wind; wind eddies/ strong upslope air movement is expected, which may cause erratic fire behavior; radiant heat transfer between slopes facilitates spotting/ ignition on the opposite canyon side. • Wide Canyon- Prevailing wind direction is not significantly altered; aspect is a significant contributor to fire behavior. Wide canyons are not as susceptible to cross-canyon spotting except in high winds. • Box Canyon/ Chute-Air is drawn in from the canyon bottom, resulting in strong upslope drafts. No gaps or prominent saddles to let heated air escape. Fires starting at the canyon bottom can rapidly move upslope due to chimney-like preheating of the higher-level fuels and upslope winds.

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Vegetation/ Fuel
City-owned open space in Laguna Niguel contains a variety of native and naturalized vegetation typical of the coastal hills bioregion. These include coastal scrub, annual grassland, riparian vegetation, and mixed chaparral, all of which are documented in the City's Biological Resources section within the General Plan Environmental Impact Report (EIR) (2025). Together, the described foliage forms the dominant natural vegetation types across more than 2,200 acres of open space within the City.

Dudek evaluated the vegetation and fuels present within the City's open space areas through a combination of research on existing vegetation cover and fuel model maps and field assessments of the weed abatement areas.

Field assessments were conducted in collaboration with City staff knowledgeable about the weed abatement areas and the annual treatment work. Common fuels include:
• Coastal Sage Scrub is interspersed within the City's open space network. It consists of low to moderate-sized shrubs with semi-woody stems, flexible branches, and mesophytic leaves. These shrubs typically occur on dry slopes- especially south-facing hillsides- and tolerate low annual rainfall and shallow soils. Coastal scrub may also occur on terraces, moderate slopes of any aspect, and stabilized dunes. • Grasslands within City-owned open space are characterized by open expanses of herbaceous vegetation dominated by non-native herbaceous vegetation and grasses, typically in flatter or gently rolling areas.

Common species include wild oats, soft chess, ripgut brome, red brome, wild barley, and foxtail fescue.

Within the weed abatement areas, black mustard and artichoke thistle are the most abundant herbaceous plant species. These grasslands often occupy lower slopes, disturbed areas, or former grazing lands where scrub vegetation was previously removed.
• Riparian vegetation occurs along drainage corridors and creek channels within the City's open space, where elevated soil moisture supports a multi-layered plant community. These areas typically include a tall canopy, a defined subcanopy, and a dense understory composed of moisture-dependent shrubs and vines.

Herbaceous vegetation also occurs in shaded or open patches where conditions support its growth.

Riparian corridors function as biologically rich, linear habitats that provide important ecological value and serve as movement pathways for wildlife within the broader open space system. • Chaparral occurs in smaller, more fragmented patches within the City's open space system but remains an important vegetation type in the coastal hills bioregion. Mixed chaparral is a dense, woody shrubland dominated by evergreen species with thick and stiff leaves adapted to hot, dry conditions. These shrubs form either pure stands or diverse mixtures, often on steep hillsides and higher-elevation slopes within the San Joaquin Hills.

Vegetation mapping within this municipal open space is a critical component of fire planning, as each vegetation community can be associated with fuel characteristics that influence potential fire behavior (Sugihara et al., 2006).

Native shrublands possess higher moisture content but can burn under severe wildfire conditions, while grasslands and non-native herbaceous cover create lighter, more rapidly ignitable fuels.

Vegetation Dynamics
Variations in vegetative cover type and species composition have a direct effect on fire behavior. Some plant communities and their associated plant species have increased flammability based on plant physiology (resin content), biological function (flowering, retention of dead plant material), physical structure (bark thickness, leaf DUDEK 5
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size, branching patt erns), and overall fuel loading. For example, non-native grass-dominated plant communities become seasonally prone to ignition and produce lower intensity, higher spread rate fires. In comparison, sage scrub can produce higher heat intensity and higher flame lengths under strong, dry wind patt erns, but does not typically ignite or spread as quickly as light, flashy grass fuels.

C lim at e
As mentioned above, the City is located approximately 5 miles east of the Pacific Ocean. Southern Orange County and the City are influenced by the Pacific Ocean and are frequently under the influence of a seasonal, migratory subtropical high-pressure cell known as the "Pacific High." Wet winters and dry summers with mild seasonal changes characterize the Southern Califo rnia climate. This climate patt ern is occasionally interrupted by extreme periods of hot weather, winter storms, or dry, easterly Santa Ana winds. The average elevated temperature for the proposed Project Area peaks at approximately 78 °F in August, with daily highs in the summer and early fall months (July- September) exceeding 85 ° F. Precipitation typically occurs between November and March, with annual totals averaging approximately 11 .4 inches (Weather Spark, 2026).

The prevailing wind patt ern is from the west (onshore), but the presence of the Pacific Ocean causes a diurnal wind pattern known as the land/ sea breeze system. During the day, winds are from the west- southwest (sea), and during the night, winds are from the northeast (land). The highest wind velocities are associated with downslope and canyon winds. Surface winds can also be influenced locally by topography and slope variations. The site is subject to periodic extreme fire weather conditions that occur throughout substantial portions of Orange County.

Fires can be a significant issue during summer and fall, before the rainy period, given onshore and Santa Ana wind events. Santa Ana wind conditions are a reversal of the prevailing southwesterly winds in Southern California. They are dry, warm winds that flow from the higher desert elevations in the east towards the coast. As they funnel through mountain passes and canyons, their velocity increases, resulting in strong, gusty winds. Although Santa Ana wind events can occur any time of the year, they generally occur during the autumn months, although the last few years have resulted in spring and summer Santa Ana wind events. Both onshore and Santa Ana winds increase wildfire danger and intensity in the Project Area by drying out and preheating vegetation as well as accelerating oxygen supply, thereby making possible the igniting and burning of fuels that otherwise might not burn under cooler, moist conditions. While Santa Ana winds are typically associated with large fire growth in inland Orange County, they are less impactf ul to the communities near the coast. In Laguna Niguel, onshore winds create the strongest winds, and these strong onshore winds are more important for large fire growth in the City and have been associated with the spread of recent large fires, including the 2022 Coastal Fire, which occurred on steep slopes aligned with onshore winds.

Fire danger is at its highest in the City when extreme wind events are typically accompanied by very low humidity, resulting in critically low fuel moisture levels in both live and dead vegetation, which lead to vegetation that readily ignites and fires that spread rapidly. The National Weather Service (NWS) issues fire weather warnings when weather conditions cross the threshold for extreme fire danger. The highest level of fire weather warning is a Red Flag Warning (RFW). RFWs are issued when a combination of high temperature, high winds, and low relative humidity exceeds a threshold established by the NWS. When RFWs are issued and how frequently they are issued are good indicators of when fire danger is typically greatest for a location. (See Appendix E, Graphs, specifically Graph 1, Historical Occurrence of Red Flag Warnings in Los Angeles and Orange Counties.) DUDEK 6
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Fire History
Fire history is a critical component of the native landscape. Fire history data provides valuable information regarding fire spread, fire frequency, fire type, the most vulnerable Project Areas, and significant ignition sources, amongst others. One important use for this information is as a tool for pre-incident planning. It is advantageous to know which areas may have burned recently and therefore may provide a tactical defense position, what type of fire burned on the Project, and how a fire may spread. The fire history in this plan is based on the California Department of Forestry and Fire Protection (CAL FIRE) Fire and Resource Assessment Program (FRAP) database. FRAP summarizes fire perimeter data dating to the late 1800s, but it is incomplete due to the fact that it only includes fires over 10 acres in size and has incomplete perimeter data, especially for the first half of the 20th century (Syphard & Keeley, 2016). However, the data does provide a summary of recorded fires and can be used to show whether large fires have occurred in the Project Area, which indicates whether they may be possible in the future.

According to available data from CAL FIRE in the FRAP database, 5 fires have burned within the Project Area since the beginning of the historical fire data record (early 20th century). Recorded wildfires within 2 miles of the Project range in size from approximately 1.33 acres up to 202.09 acres (2022 Coastal Fire).

Wildfire Occurrence within the City of Laguna Niguel as shown in the FRAP database:
■ 2022 Coastal Fire (202.0 acres)
■ 1979 Niguel Fire (135 acres)
■ 1979 Ortega Fire (302.4 acres)
The surrounding landscape of Orange County has experienced fires of varying sizes and intensities, including the recent 2024 Airport Fire (23,526 acres in the Santa Ana Mountains), the 2020 Silverado Fire (12,469.21 acres), and the 2020 Bond Fire (6,681.1 acres). Smaller fires less than 10 acres, including the Niguel Fire (2017), Laguna Niguel Regional Park Fire (2017), Niguel Fire (2023), and the Beacon Fire (2025), are not included in the FRAP database.

Land Ownership
Laguna Niguel contains 4,309 acres of open space, but only a small portion of this land is owned and managed by the City (651 acres). A substantial share, approximately 1,541 acres, is owned by homeowners' associations (HOAs), which typically maintain neighborhood private parks, landscaped slopes, and private greenbelts that are not always accessible to the general public. In addition, the county, utility companies, and other public agencies are responsible for 920 acres of open space, including regional parklands and natural habitat areas that contribute to the City's expansive undeveloped landscape yet fall outside municipal control. By contrast, the City of Laguna Niguel owns only 651 acres, encompassing public parks, trail corridors, and selected natural areas, representing roughly 15 percent of total open-space acreage.

Much of the natural open-space network in the City, including areas such as the Salt Creek Corridor, lies within State-designated Fire Hazard Severity Zones, which classify land as Moderate, High, or Very High fire hazard based on vegetation, terrain, and wildfire behavior modeling. These designations indicate elevated wildfire risk in such natural preserves, making them areas of ongoing concern for the City's fire-hazard mitigation and planning efforts.

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roughly 15%. Of that 15% under direct City ownership and Management, only 2% is in the Very High Fire Hazard Severity Zone.

Table 1 provides a detailed description of the specific acres in each ownership category for the 4,309 acres of open space land in the City. Figure 2 shows the location of the Fire Hazard Severity Zones in the City. Included in Figure 3 is a map of the City's Very High Fire Hazard Severity Zone overlaid with City-owned open space.

As a result, while the City visually contains extensive open space, the maj ority (85%) is controlled by HOAs, the county, or private owners, leaving a comparatively small portion under direct City ownership and management, roughly 15%. Of that 15% under direct City ownership and Management, only 2% is in the Very High Fire Hazard Severity Zone.

Table 1. Open Space Landownership in Laguna Niguel
City- HOA- Privately County-
Total Owned Owned Owned Owned Other Publicly
Open Space Category Acreage Acres Acres Acres Acres Owned Acres Developed Parks and 643 197 80 188 152 26
Special Use Areas
Landscaped or Maintained 1,673 28 887 665 46 47
Vegetation Areas
Natural Areas 1,269 354 179 173 561 2
Partially Maintained 724 72 395 171 85 1
Natural Areas
Total Acreage by Owner 4,309 651 1,541 1,197 844 76
Source: City of Laguna Niguel
Geolog ic Hazard and Landslid e History
Laguna Niguel faces ongoing geologic hazard risks due to its steep coastal hills and canyon areas, where saturated soils, groundwater changes, and seismic activity can destabilize slopes. The City's Local Hazard Mitigation Plan (2023) identifies landslides as a medium probability and medium impact hazard. A major indicator of this vulnerability occurred during the 1998 El Nino storms. As noted in the City's Local Hazard Mitigation Plan multiple slope failures at Vista Plaza Drive, Alicia Parkway, La Paz Road, and Via Estoril caused home collapses, structural damage, and widespread evacuations (City of Laguna Niguel 2023). These events highlight the importance of conservative hillside management.

Vegetation management is central to reducing landslide risk. The City requires minimal soil disturbance during vegetation management activities so that root systems remain intact. Exposed bare mineral soil increases surface water runoff, rapidly increasing soil erosion. Preserving root networks supports soil stability and reduces erosion and debris-flow hazards, particularly in post-fire or high-risk areas. Geologic susceptibility mapping by the California Geological Survey guides development review and slope-stability assessments. Changing climate conditions, including more intense rainfall and increased vegetation loss, may increase the likelihood of landslides in the future, reinforcing the need for careful vegetation maintenance and strict hillside grading controls (City of Laguna Niguel 2023).

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Vegetation treatment techniques used in the City's weed abatement areas and by HOAs and private landowners on properties adjacent to weed abatement areas need to balance meeting OCFA standards and maintaining soil stability to prevent excessive erosion or run-off . Vegetation treatments should conserve plant root structures. Above­ ground portions of grass and herbaceous plants should be cut to the OCFA required height (4 inches), but should not create large areas of bare earth. Shrublands should have the overall continuity and volume of vegetation reduced, but individual shrubs or small groups of shrubs should be retained, and the below ground root systems should be left intact. Based on Dudek's field observations. these best practices are actively being implemented and should be maintained to achieve an appropriate balance between vegetation management and soil stability.

Planning and Regulatory Environment
Vegetation management and wildfire-risk reduction in Laguna Niguel are governed by a layered system of regulations that operate at the local, regional, and state levels. Together, these standards establish where defensible-space treatments are required, how fuel modification must be designed and maintained, and what responsibilities apply to both private property owners and the City for its publicly managed open space. The following sections summarize the key components of this framework.

OCFA Standards
Under the Orange County Fire Authority (OCFA) RSG Vegetation Management Guidelines (Appendix F), all property owners within or adjacent to wildfire hazard areas (State Responsibility Areas or Local Very High Fire Hazard Severity Zones) must maintain a fuel modification zone for lands within 100 feet of a structure. Defensible space is designed to reduce fire intensity and protect structures (OCFA 2026). The standard defensible space area extends to 100 feet horizontally from the structure. The OCFA Fire Code Official may determine that certain properties are at a higher risk from wildfire and require these property owners to maintain an area greater than 100 feet from the structure. If City open space areas are outside mapped wildfire hazard zones, OCFA fuel modification requirements may not formally apply. The defensible space area is divided into the following zones:
• Zone A - Immediate Zone (0-5 feet from the structure) Represents the primary non-combustible buffer.

Typically, on private property, not City-owned or managed land. • Zone B - Intermediate Zone (5-30 feet)
Irrigated or thinned zone with fire-resistant plants, no dense shrubs.

Often overlaps private rear yards and is adjacent to City open space. • Zone C - Outer Thinning Zones (30 to 100 feet beyond Zone B) Natural vegetation is selectively thinned with spacing determined by slope.

More often on City or HOA-managed open space.

All property owners are required to maintain this 100-foot area. completing all vegetation management work prior to the onset of fire season in the summer. when hot and windy weather is more likely. The OCFA has supplemental standards for Fuel Modification Zones, Special Maintenance Areas, and Roadside Protection Zones. Each is discussed in further detail below:

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■ Fuel Modification Zones (FMZs) are required with all new single-family homes, new multi-family residential, Accessory Dwelling Unit (ADU), utility, and commercial structures built in, or adjacent to, a wildfire-risk area. ■ Special Maintenance Areas (SMAs) are interior slopes or landscaped common areas within residential tracts, typically up to 100 feet wide, that are not located on the community perimeter but could carry fire or embers between structures. These areas, when located within 100 feet of a structure, per 0CFA standards, must meet the same defensible space spacing and maintenance requirements applied to FMZs. ■ Roadside Protection Zones (RPZs) are vegetated strips or slopes along roadways, generally at the community perimeter or along designated evacuation routes, extending up to 50 feet from the roadway edge. RPZs must be irrigated and planted with low-fuel, fire-resistant vegetation, remaining free of ladder fuels and other combustible materials. When located within 100 feet of structures, RPZs are treated as defensible space zones under 0CFA standards.

Local and State Fire Codes
The City of Laguna Niguel Fire Code adopts the California State Fire Code and incorporates local amendments that address vegetation management, defensible space, and property maintenance within the City limits as recommended by 0CFA. Under this code, property owners, including the City for publicly owned parcels, are required to maintain vegetation in a condition that prevents the spread of fire from wildland areas to structures. The City's responsibility for its open space areas is also required under this code, ensuring that vegetation within City­ managed lands is maintained to meet defensible space and fuel reduction standards. This includes removing or reducing combustible vegetation, maintaining a minimum 100-foot defensible space around habitable structures, and ensuring that landscaped areas near buildings remain irrigated and free of dead or dying material.

The Fire Code also authorizes the City to operate an annual weed abatement program that enforces vegetation clearance requirements on both private and public property. Parcels identified as potential fire hazards are inspected each spring, and non-compliant properties receive a Notice to Abate prior to any further enforcement action by the City.

At the state level, wildfire protection and vegetation management requirements are governed by the California Wildland-Urban Interface Code (CWUIC), California Fire Code (CFC), California Building Code (CBC), Public Resources Code (PRC) Section 4291 (California Building Standards Commission 2022; California Public Resources Code 2023), and Government Code (GC) 51182. These regulations establish minimum statewide standards for defensible space and fire-resistant construction in areas designated as State Responsibility Areas (SRAs) and Local Responsibility Areas (LRAs) that contain Very High Fire Hazard Severity Zones (VHFHSZs).

PRC §4291 and GC 51182 mandate that property owners maintain up to 100 feet of defensible space around all structures by removing flammable vegetation and maintaining fire-resistant landscaping. The CFC extends this requirement to local jurisdictions such as Laguna Niguel and authorizes local fire authorities, like 0CFA, to enforce these provisions through inspection, permitting, and abatement programs.

The State Fire and WUI Code (Chapter 3) also references CAL FIRE's Fire Hazard Severity Zone (FHSZ) maps, which classify lands as Moderate, High, or Very High hazard based on vegetation, slope, and weather factors. Development and vegetation management requirements are triggered by these designations, including the use of fire-resistant building materials and permanent fuel-modification areas, consistent with 0CFA Guideline C-05 (0CFA 2026). For this study's mapping and initial assessment, a 100-ft defensible space area was utilized around all structures. City- DUDEK 10
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owned open space areas within this area were reviewed in detail to determine where vegetation management would be required or beneficial to nearby structures and improvements.

Purpose of Defensible Space and Fuel Breaks
An important part of understanding the conclusions of this report is understanding the role of vegetation management in the Wildland Urban Interface in reducing wildfire risk. The section defines terms used throughout this report and outlines the role vegetation management plays in protecting communities in Laguna Niguel.

Vegetation management for wildfire risk reduction can be carried out for various reasons, including creating strategically advantageous locations for firefighting, reducing ignition risks (e.g., new fires) in areas with frequent fires, and protecting structures from wildfire ignition. The City's current vegetation management program, like those in communities throughout California, focuses on public safety and on safeguarding nearby structures from wildfires. Specifically, it aims to lower the risk that these structures will ignite due to extreme fire behavior, such as crown fires and long-range spotting.

Vegetation management areas limit fuel continuity, decrease flame lengths, slow the rate of fire spread, and reduce direct heat exposure by decreasing available fuel for a wildfire. Defensible Space and Vegetation Management zones are designed not to stop wildfire spread but to reduce the fire's intensity and rate of spread. Additionally, long-range spotting- firebrands lofted by the wildfire's hot gases and smoke and carried beyond the immediate fire zone (NWCG 2026)- are not significantly mitigated by defensible space and fuel breaks. Dudek does not recommend installing firebreaks, removing all vegetation, and leaving bare ground in City open space areas due to erosion concerns, and they are not considered in the Findings/ Recommendations. Importantly, 0CFA guidelines specifically state that complete vegetation removal is neither recommended nor required as a general practice (OCFA 2026).

Dudek does not recommend installing fire breaks, removing all vegetation, and leaving bare ground in City open space areas due to erosion concerns, and they are not considered in the Findings/ Recommendations. Importantly, 0CFA guidelines specifically state that complete vegetation removal is neither recommended nor required as a general practice (0CFA 2026).

The City's vegetation management program consists of 11 weed abatement areas, totaling 44 acres. These 11 areas cover hillsides on City-owned open space areas near homes on the adjacent properties. To ensure ongoing best practices in these weed abatement areas, the City maintains the vegetation in these areas to meet 0CFA's vegetation management guidelines within 100 feet of structures. Due to the location and configuration of the weed abatement areas, the City's vegetation management program combines elements of defensible space and fuel breaks.

To ensure ongoing best practices in these weed abatement areas, the City efficiently maintains the vegetation to meet 0CFA '.s vegetation management guidelines within 100 feet of structures.

Figure 4 illustrates the 11 existing weed abatement areas as listed in Table 2 below. Detailed information for each of the City's existing Weed Abatement areas is shown in Figures 5i - 5xi.

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Table 2. Existing Weed Abatement Areas
Weed Abatement Area Approximate Acres
1) Kite Hill 1.79 acres
2) La Hermosa Park 16.92 acres
3) Pienza 0.33 acres
4) Denia 0.9 acres
5) George White Elementary/ Redondo View Node 5 acres
6) Reef View Node 2.8 acres
7) Phillips Circle 0.68 acres
8) Russel Lane 1.3 acres
9) Catamaran Way 0.83 acres
10) Bear Brand Park 1.79 acres
11) Longview Park 4.33 acres
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Analysis and Recommendations
Wildfire Risk Assessment & Modeling Results
Wildfire hazard represents the existing wildfire environment and potential wildfire behavior. A comprehensive wildfire hazard assessment was conducted for the Project Area using FlamMap to evaluate potential wildfire exposure, intensity, and fire spread within the City. Flam Map is a fire behavior modeling tool that estimates potential fire behavior across an entire landscape. Flam Map was developed by the U.S. Forest Service and is commonly used by firefighting agencies for predicting fire behavior (spread rate, flame length, fireline intensity, etc.), which is useful for planning and risk assessment, and well-suited for comparing risk and mitigation across large areas. • The analysis relied on a 10-meter-resolution Landscape Base file that included terrain characteristics (elevation, slope, aspect) and vegetation/ fuel inputs (fuel model and canopy characteristics), along with locally derived 90th- and 97th-percentile weather conditions to capture both severe summer onshore winds and peak Santa Ana offshore wind events.
• This assessment incorporated two key components: flame-length modeling and burn-probability modeling.

Flame length and burn probability were combined to produce a relative wildfire hazard layer based on wildfire intensity and probability across the landscape. • Collectively, these analyses provide a landscape-scale understanding of wildfire hazard and behavior, informing the wildfire mitigation planning for the City.

To initiate the modeling effort, a Landscape Base file was created and analyzed. The Landscape Base file consisted of seven distinct data layers representing terrain (elevation, slope, and aspect) and vegetation/ fuels (fuel model designation, canopy cover, canopy height, and canopy base height). The Landscape Base file was created within the City and a surrounding 2-mile buffer area to account for adjacent wildfire hazards. Landscape file data were created at a 10-meter scale using the data sources presented in Table G-1 in Appendix G, Additional Tables.

Fuel model data was obtained from the Orange County Vegetation Map produced by the Natural Communities Coalition (NCC), which maps roughly 86,000 acres of vegetation communities located within the Central and Coastal Subregions of Orange County.
• This dataset was primarily based on interpretation of 2022 NAIP 1-meter aerial imagery, supplemented by higher-resolution 2022 Hexagon imagery and historical imagery (e.g., Google Earth and 2012 datasets) to help identify vegetation types, delineate stands, and confirm changes over time. Photo interpreters also relied on multiple ancillary datasets, including prior vegetation maps, fire history, field data, and topographic information, to support classification and mapping decisions. • Vegetation classifications were then crosswalked into the appropriate fire-behavior fuel models. In areas within the City where vegetation types were not included in this dataset, fuel model datasets were obtained from LANDFIRE's 2024 fuel model dataset and resampled to 10 meters.

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Flame Length
Flame length is the length of the flame of a spreading surface fire within the flaming front, measured from midway in the active flaming combustion zone to the average tip of the flames (Andrews et. al. 2008). It is imperative for fireline personnel to evaluate fireline intensity, and it is a vital wildfire variable (Rothermel, 1993). Table 3 summarizes flame length measurements and provides an interpretation related to suppression efforts.

Table 3. Flame Length and Suppression Efforts
Flame Length Interpretation
Under 4 feet Fires can generally be attacked at the head or flanks by persons using hand tools. Hand line should hold the fire.
4 feet to 8 feet Fires are too intense for a direct attack on the head by persons using hand tools. Hand line cannot be relied on to hold the fire. Equipment such as dozers, pumpers, and retardant aircraft can be effective.
8 feet to 11 feet Fires may present serious control problems- torching out, crowning, and spotting. Control efforts at the fire head will probably be ineffective.

Over 11 feet Crowning, spotting, and major fire runs are probable. Control efforts at the head of the fire are ineffective.

Flame lengths are a good visual indicator of fire intensity and can be used by firefighters to determine which fires may be difficult to contain using direct tactics (e.g., attacking the flames at the front (head) or sides (flanks) of a fire). Exhibit 1 shows the typical appearance of the flame lengths and fireline intensities described in Table 3.

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Exhibit 1. Fire Observation/ Description
Running Torch/ Spot Crowning Erratic &
Extreme
I ._. ••
• No open flame • Visible open • Organized • Organized • Organized • Organized in surface fuels flame, 1-4 ft. surface flame surface flame crown fire crown fire • White smoke in surface fuels front, UJL in front, 8-12 ft. front front • Smoldering • Surface fire surface fuels in surface fuels • Moderate to • Moderate to ground fire only • Moderate rate • Moderate to long range long range • Unorganized of spread fast ROS on spotting spotting
flame front • Vigorous the ground • Independent • Independent • little or no surface fire • Grey to black spot fire spot fire spread • May see some smoke growth growth
candling or • Torching/Short • Black to • Presence of
torching along range spotting copper smoke fire balls and the perimeter • Disorganized • 12-18 ft whirls
and/or within crown flames in open • Violent fire
the fire involvement and slash fuels behavior
Image source: National Wildfire Coordinating Group (NWCG) Flame length modeling was conducted in FlamMap using the landscape file inputs provided in Table G-1 in Appendix G, along with custom weather parameters based on local conditions. Wildfire behavior modeling is typically conducted during two weather scenarios to provide a comprehensive assessment of wildfire throughout the fire season. This concept is typically referred to as the 90th and 97th percentile weather conditions.

In fire weather forecasting and fire behavior modeling, the terms 90th percentile and 97th percentile refer to statistically derived weather conditions based on a historical record of observations (e.g., temperature, humidity, wind, and fuel moisture). These percentiles are used to represent severe or extreme conditions that strongly influence fire ignition, spread, intensity, and suppression difficulty. They are not simple thresholds but indicate how rare and extreme the conditions are relative to typical weather history for the same location and season.

For this assessment, 90th percentile weather conditions are representative of worst-case summer weather with onshore winds, while 97th percentile conditions represent peak Santa Ana conditions with rapid offshore wind speeds. Values for the 90th and 97th percentile weather were obtained from the Aliso Laguna Remote Automated Weather Station (RAWS) located roughly 1 mile west of the City's western edge. Weather data was processed in the DUDEK 15
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Fire Family Plus soft ware package to determine fuel moisture and wind inputs. Weather values for the 90th and 97th-percentile weather are provided in Table G-2 (Appendix G).

To identify worst-case fire behavior conditions, results from the 90th and 97th percentile weather scenarios were overlaid to capture the longest modeled flame lengths across a range of potential weather patterns. • Although the 97th percentile weather scenario generally produces the most extreme fire behavior due to hott er, drier, and windier conditions, the analysis showed that in some areas the 90th percentile scenario resulted in higher flame lengths.
• This occurred where steep slopes were aligned with the prevailing onshore wind direction, as represented in the 90th-percentile weather inputs, which can accelerate upslope fire spread and increase flame lengths. • By combining results from both scenarios, the analysis ensures that the final output accounts for the most severe fire behavior that could occur under differing yet plausible weather conditions.

Burn Probability
In FlamMap, burn probability is modeled by simulating thousands of potential fires across a landscape and calculating how often each location burns under a defined set of fuel, weather, and topographic conditions. The model uses spatial inputs such as vegetation and terrain, along with constant (static) weather and fuel moisture conditions.
• Ignitions are randomly distributed across the landscape, and each ignition is modeled using the Minimum Travel Time (MTT) fire spread tool to simulate how fire would spread over a specified duration. As each simulated fire spreads, the model records which pixels burn. After all simulations are complete, the number of times each pixel burns is divided by the total number of ignitions to produce a burn probability value between 0 and 1.
• These values represent the relative likelihood that a given location would burn if a fire were to occur somewhere on the landscape under the modeled conditions, highlighting areas of greater wildfire exposure driven by fuels, terrain, and wind patterns rather than ignition likelihood. Burn probability is related to the size of fires that occur on a given landscape, where larger fires produce higher burn probabilities than smaller fires. The following equation summarizes the burn probability calculation:

Burn Probability= number of times burned/ total number of ignitions Given that the Project Area experiences both extreme offshore winds and typical summer onshore winds, the burn probability output represents a weighted average of burn probabilities modeled under each of these weather conditions (see Table G-2 in Appendix G). Similar to flame-length modeling, gridded winds were used to model fire spread and burn probability, which is performed using the WindNinja program embedded in FlamMap. Gridded winds alter wind flow across the landscape based on topographic effects (e.g., the drag effect vegetation has on wind flow). Gridded winds more accurately model the effects of complex terrain (e.g., funneling through narrow canyons) during directional wind events.

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Relative Wildfire Hazard
A City-wide relative wildfire hazard assessment was conducted in FlamMap, integrating the flame-length (representing fire intensity) and burn-probability outputs. Determining wildfire hazard involves combining two important measures- burn probability and flame length- into a single spatial wildfire hazard output layer. The relative wildfire hazard modeling analysis generates five hazard classes based on the intersection of burn probability and flame length, as shown in Exhibit 2.

Exhibit 2. Relative Wildfire Hazard Classification Matrix Burn Probability Classes
rn Lowest Lower a,
rn 0-20% 20-40% rn ca of max of max 0 .c > 12 ft
- C> C >8 - 12ft a,
...J
a, >6 - 8 ft E
..!!! >4 - 6 ft ~
'C >2 - 4 ft C
0 >0 - 2 ft t)
Middle Higher
40-60% 60-80%
of max of max
Highest
80-100%
of max
Lowest Lower Middle Higher
Hazard Hazard Hazard Hazard
Highest
Hazard
Wildfire Hazard Modeling Results
Results of the wildfire hazard assessment are provided in Figures (6-9) and display outputs for flame length, burn probability, and relative wildfire hazard.

Flame Length
Modeled flame lengths within City-owned open space areas vary considerably and are highly dependent on vegetation and terrain, with brushy areas on steep slopes exhibiting the longest flame lengths and highest intensity fires. Within the City-owned open space areas, steep slopes (>25%) are common, particularly where the open space transitions to developed areas and to the landscaped hillsides between the open space and the nearest homes or streets.

Vegetation cover varies across the City's open space areas; however, annual grasslands are the most prevalent vegetation type, with coast sage scrub the second most common, particularly within the VHFHSZ (Aerial Information Systems 2022). Higher-load chaparral fuels are also present in City open spaces, albeit less common than in grasslands and coastal scrub. Acacia is common in the HOA-owned hillsides adjacent to the City-owned open space DUDEK 17
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between the developed and undeveloped areas. In the annual grasslands, flame lengths were modeled at roughly 8 feet under typical fire-season conditions3 and up to 14 feet during periods of extreme fire dangers. Expected flame lengths within the coastal sage scrub were modeled to be higher than the annual grasslands due to the greater density and volume of combustible vegetation, at 13 feet during typical fire season conditions and roughly 25 feet during periods of extreme fire danger.

Topographic conditions further influence these fire-behavior patterns. Flame lengths tend to increase along ridgelines and in areas where slopes are aligned with prevailing wind directions. Under these conditions, wind speeds can accelerate as they move over ridges and through canyons, while upslope fire spread can preheat and dry fuels ahead of the fire front. The combination of wind alignment and slope can substantially increase the rate of spread and flame length, resulting in more intense, difficult-to-control fire behavior in these locations.

As presented in Figures 6 and 7, the highest intensity fire behavior is actually most prevalent outside of City-owned open space areas and in larger areas of high load chaparral vegetation. Chaparral is found primarily in the southwestern region of the City, where steeper slopes and less-disturbed open space support southern mixed chaparral, chamise chaparral, and southern maritime chaparral communities. Chaparral habitats have the potential for a high rate of spread, rapid ignition, and extreme fire behavior given their high content of volatile organic compounds.

As presented in Figures 6 and 7, the highest intensity fire behavior is actually most prevalent outside of City-owned open space areas and in larger areas of high load chaparral vegetation.

Figures 6 and 7 illustrate the modeled flame lengths under typical fire-season conditions and during extreme fire­ danger periods. Figure 7 presents the maximum (worst-case) flame lengths, representing the highest values observed across both weather scenarios.

Burn Probability
Burn probability is strongly influenced by the potential for wildfire to spread across large, continuous areas of vegetation. Accordingly, higher burn probability within the City generally corresponds to locations where modeling indicates that larger wildfires are more likely to occur and propagate through extensive, uninterrupted fuel beds, such as open space preserves and undeveloped wildlands. These contiguous areas allow fires to spread more efficiently and sustain longer runs, increasing the likelihood that any given location will burn during simulated fire events.

In contrast, smaller and more fragmented open space areas tend to exhibit lower burn probabilities, as fire spread is more readily disrupted by development, roads, and other fuel breaks that limit fire growth and constrain overall fire size. However, where smaller open space areas are connected with continuous fuels, including landscaped hillsides on HOA or privately owned properties, these features can facilitate fire spread between otherwise isolated fuel patches. This connectivity effectively increases the potential size and duration of wildfire events, resulting in elevated burn probabilities along these linked open space networks. 3 Under 'Peak' Summer Weather Conditions
4 Extreme fall weather conditions
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As shown in Figure 8, composite burn probability considering both Santa Ana and peak summer conditions is highest within large, well-connected open space areas. Burn probability is elevated in the Aliso Canyon region due to extensive wild land fuels, topographic conditions that promote fire spread, and the potential for high-intensity fire behavior. Among City-owned lands, the fire risk analysis identified the Salt Creek Corridor as having the highest modeled burn probability. This determination is a combination of its large size and continuous vegetation cover, with the alignment of Salt Creek and onshore winds. Elevated burn probability is also observed within the Crown Valley Park open space area.

Relative Wildfire Hazard
As described earlier in this report, the relative wildfire hazard assessment integrates fire behavior modeling outputs for flame length and burn probability to evaluate where areas of both high wildfire intensity and higher likelihood of burning occur across the City. This approach provides a more comprehensive understanding of wildfire hazard than either metric alone, as it captures both the potential intensity of fire behavior and the likelihood that a given area will experience wildfire. This analysis provides a relative comparison of wildfire hazard rather than an absolute hazard rating. Hazard classes reflect how areas compare to one another within the City based on local landscape and fuel conditions.

These locally derived hazard maps differ from the statewide hazard classifications produced by CAL FIRE's Fire Hazard Severity Zone (FHSZ) maps, which are developed using standardized modeling approaches and datasets applied consistently across the entire state. While statewide maps provide an important regulatory and planning framework, their coarse resolution and uniform methodology may not fully capture localized conditions, such as site-specific vegetation patterns, fine-scale topography, fuel continuity, and locally dominant wind patterns.

Relative wildfire hazard was categorized into five classes ranging from Very Low to Very High. Figure 9 shows the Relative Wildfire Hazard map for the City. Areas classified as Very Low represent locations with comparatively lower modeled hazard, generally associated with lower burn probability, lower predicted flame lengths, or both. At the opposite end of the scale, Very High represents areas with the highest relative hazard, where the modeling indicates a combination of elevated burn probability and the potential for more intense fire behavior, including longer flame lengths. Intermediate classes (Low, Moderate, and High) represent progressively increasing levels of relative hazard between these two extremes. Mapping these relative hazard classes provides a spatial understanding of how wildfire hazard varies across the City's open space areas and a useful framework for prioritizing vegetation management, fuel treatments, and other wildfire mitigation strategies in locations where wildfire intensity and likelihood intersect.

It is not unusual for larger, more continuous open space areas to receive higher relative hazard scores, since hazard rankings are strongly influenced by the likelihood of wildfire occurrence. These landscapes typically contain more continuous vegetation fuels and are more likely to experience fire spread over time compared to smaller or more fragmented open space areas. When these larger open spaces also contain higher-hazard vegetation types, such as dense chaparral or coastal scrub, capable of supporting intense fire behavior, the resulting hazard classifications tend to be higher.

Interestingly, many of the areas identified as having the highest relative wildfire hazard are located outside of City­ owned open space areas in the City's southwestern region. In this portion of the City, open space areas are generally larger, exhibit higher fuel loads, and are more directly connected to surrounding wildland landscapes outside the City boundary. Additional areas of elevated hazard outside the City boundary occur adjacent to the City's eastern DUDEK 19
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edge (part of the Colinas de Capistrano community), where terrain and steep slopes exacerbate fire behavior during Santa Ana weather conditions. Larger distributions of higher relative wildfire hazard areas within City-owned open space areas include the Salt Creek Corridor, Crown Valley Park Open Space, and La Hermosa Park.

Vegetation Management Program Analysis
The City of Laguna Niguel conducts defensible space and vegetation management on approximately 44 acres of City-owned open space, divided into 11 areas, as shown on Figures 5-i through 5-xi, the City Weed Abatement Areas.

The current extent and location of vegetation management are determined by state regulations for defensible space, code compliance standards, and the boundaries of City-owned open space areas. According to the current state and local fire code, defensible space is only required in the areas designated as a Very High Fire Hazard Severity Zone.

Dudek's analysis of the City's current vegetation management program considered both regulatory requirements and anticipated fire behavior. The intent of our analysis is to determine if the City's current program is adequate to meet the OCFA's recommendations and provide an effective defensible space area between the natural vegetation in the open spaces and the communities adjacent to these areas. While determining if further weed abatement activities are necessary.

Regulatory Requirements
The first part of Dudek's analysis reviewed the effectiveness of the existing vegetation management program to determine whether it meets or exceeds current regulatory requirements for defensible space and fuel reduction.

State and local regulations determine where vegetation management is required, how wide an area must be managed, and how the vegetation within this area must be managed.

Where Vegetation Management is Required
Public Resource Code (PRC) 4290 and Government Code (GC) 51181 identify the areas in the state that are in a very high fire hazard severity zone (VHFHSZ). Within the VHFHSZ, state and local codes require property owners to maintain the vegetation on their property to minimize the risk that a wildfire will ignite a structure or that a structure fire will ignite a wildland fire. The City's current weed abatement program includes 11 weed abatement areas. Six of the eleven weed abatement areas (weed abatement areas #3-8) are within the VHFHSZ, and all six are located within the Salt Creek Corridor Open Space. In addition, though not required, it is the City's standard to create defensible space within 100 feet of all structures across the City that border open space.

The City's adopted standard exceeds the regulatory requirement to maintain the vegetation within 100 feet of a structure. Of the City's 44 acres in the City's Weed Abatement Program, 11 acres are located within the VHFHSZ (weed abatement areas #3-8), and the remaining 33 acres are in the High and Moderate Fire Hazard Severity Zones.

Following the adoption of the updated Cal Fire Fire Hazard Severity Zone maps in June 2025, Dudek has identified an additional recommended weed abatement area, an approximate 0.5-acre section of City-owned open space within the VHFHSZ where defensible space is not part of the City's current vegetation management program (Opportunity Area A). Opportunity Area A, located in the southwest corner of the Salt Creek Corridor Open Space at the rear of the homes on Champany Place, Coplay Place, Ticknor Place, and Rollins Place, was not a requirement DUDEK 20
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prior to the adoption of the updated VHFHSZ map. Due to the varying setbacks of the homes at the end of these streets, the 0.5-acre is broken up into three small strips rather than a continuous area behind the four streets.

While responsibility for providing defensible space in Opportunity Area A primarily rests with the HOA, it is recommended that the City, consistent with its current practices, conduct supplemental abatement activities within City-owned open space to achieve a full 100-feet of defensible space, as shown in Figure 10, Weed Abatement Opportunity Area A.

Vegetation Management Area Width
Within the VHFHSZ, PRC 4291, GC 51182, and Laguna Niguel Municipal Code Section 11-3-11, a 100-foot defensible space is required around all structures. This area must be maintained to minimize the risk of structure ignition, in accordance with OCFA's RSG Vegetation Management Guidelines document. This 100-foot area begins at the exterior of the structure and extends outward horizontally. Within the VHFHSZ, where homes along the boundaries between residential communities and City-owned open space are close to the boundary (within 100 feet}, a portion of the 100-foot area may extend onto City-owned open space. Outside of the VHFHSZ, Laguna Niguel Municipal Code Section 11-3-4 requires vegetation capable of being ignited and endangering property to be maintained according to the requirements in the CWUIC.

As noted throughout this report, the maintenance of the 100-foot area around all structures adjacent to City-owned open space can be the responsibility of several agencies or property owners, including the nearby homeowners, an HOA, or another public agency (e.g., County of Orange). While the City's weed abatement areas sufficiently cover the 100-foot requirement around adjacent structures, they do not extend past City-owned property. As a result, several of the weed abatement areas abruptly end at the City property line due to interspersed private property lines rather than connecting between two anchor points.

Maintenance Standards within the 100-foot Area
Government Code 51182 and Section 11-3-11 of the Laguna Niguel Municipal Code create the requirements for maintaining vegetation within 100 feet of a structure. These regulations do not specify the treatment standards for this 100-foot area beyond the clearance of tree branches from structures. Specific treatment requirements for vegetation management are found in OCFA Guidelines C-05 Vegetation Management Guideline: Technical Design for New Construction Fuel Modification Plans and Maintenance Program (Appendix F), as well as the OCFA Ready, Set, Go Guidelines for Defensible Space and Vegetation Management (Appendix F).

Overall, the City's current weed abatement program and its vegetation management practices, including where vegetation is managed, how wide the managed area is, and how each type of vegetation is managed, meet or exceed OCFA recommendations. Further, the City's vegetation management practices are consistent with those implemented by neighboring cities for their own weed abatement or vegetation management programs.

Overall, the City's current weed abatement program and its vegetation management practices, including where vegetation is managed, how wide the managed area is, and how each type of vegetation is managed, meet or exceed OCFA recommendations.

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Effectiveness Versus Modeled Fire Behavior
The second part of Dudek's analysis went a step further, evaluating the effectiveness of the vegetation management program in reducing fire intensity and spread near structures, thereby reducing the risk of structure ignition. Defensible space and vegetation management requirements from local and state code, as well as 0CFA guidelines, are based on well-accepted wildfire prevention science, specifically, that a 100-foot zone of vegetation management is sufficient under typical conditions to provide a significant reduction in structure ignition risks (CAL FIRE, 2006).

Defensible space and vegetation management requirements from local and state code, as well as 0CFA guidelines, are based on well-accepted wildfire prevention science, specifically, that a 100- foot zone of vegetation management is sufficient under typical conditions to provide a significant reduction in structure ignition risks (CAL FIRE, 2006).

Dudek's wildfire analysis modeled wildfire behavior across .fill open space areas in the City. Dudek's analysis included modeling anticipated flame lengths, which are a good measure of fire intensity, with longer flames indicating a more intense fire. Generally, fuel breaks are considered effective when their width exceeds, at a minimum, twice the expected flame length (Gannon et. al. 2019). Wider fuel breaks or defensible space zones are required in areas with dense vegetation and steep slopes because the wildfire intensity is anticipated to be significantly higher (CAL FIRE, 2019).

Vegetation cover varies across the City's weed abatement areas; however, annual grasslands are the most prevalent vegetation type, with coast sage scrub the second most common, particularly within the VHFHSZ (Aerial Information Systems 2022). Acacia is common in the HOA-owned hillsides adjacent to the City-owned space between the developed and undeveloped areas. In the annual grasslands, flame lengths were modeled at approximately 8 feet under typical fire-season conditions5 and as long as 14 feet during periods of extreme fire danger6. Expected flame lengths within the coastal sage scrub were modeled to be higher than the annual grasslands due to the greater density and volume of combustible vegetation, at 13 feet during typical fire season conditions and approximately 25 feet during periods of extreme fire danger, where large patches of coastal sage scrub occur on steep slopes. In the few areas where high-load shrub fuels are present within City-owned open spaces, flame lengths are anticipated to reach roughly 50 feet.

The City's existing vegetation management program uses this 100-foot-wide zone as a basis for determining where vegetation management is required in its open space areas and how wide the vegetation management area needs to be. However, local variations in vegetation and terrain characteristics, such as steep slopes and dense chaparral, as well as extreme weather conditions, may result in conditions where a 100-foot zone is insufficient to impact the anticipated fire behavior significantly, and additional vegetation management beyond the 100-foot zone would be needed to provide adequate protection to the nearby structures. As part of this study. no areas were identified that necessitate extending the vegetation management program beyond the 100-foot zone.

Figures 6 and 7 show the modeled flame lengths under typical fire-season conditions and during periods of extreme fire danger. Using expected flame lengths associated with coastal sage scrub, which is the vegetation anticipated to burn at the highest intensity during periods of extreme fire danger, the City's current 100-foot weed abatement 5 Under 'Peak' Summer Weather Conditions
6 Extreme fall weather conditions
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zone is more than twice the projected flame length. This width is suffi cient to substantially reduce fire intensity and to prevent flames from unmanaged vegetation from reaching nearby structures or combustible materials. Thus. the 100-foot weed abatement zone does not need to be altered.

Defensible Space Versus Fuel Break
Defensible space focuses on the parcel, maintaining vegetation within 100 feet of the structure to protect it from wildfire. A fuel break is generally a wide strip of land on which vegetation has been modified so that a fire burning into it can be more readily controlled (CAL FIRE, 2019). A fuel break is intended to modify fire behavior over a larger area, such as at strategic locations to fight fires away from developed areas or to create a buffer between communities and unmanaged natural areas. Fuel breaks need to be anchored (also called Connectivity) at both ends to a feature that a fire cannot spread around, like a road, a body of water, irrigated turf, etc.

The City's existing vegetation management program includes elements of both defensible space, in that it's focused on the 100-foot area near a structure, and a fuel break, in that the maintained areas are intended to protect the adjacent communities from wildfire. Since the City's vegetation management program contains elements of a fuel break and is concerned with an area beyond the individual parcel, the areas where the City manages vegetation to protect adjacent homes must be anchored at the beginning and end to a feature that a fire cannot spread around to resume spreading towards the properties it is trying to protect.

Ownership of open space areas within the City of Laguna Niguel is complex, with responsibilities shared among more than 30 HOAs, County agencies, utilities, and the City. As a result, City-owned open space may be within 100 feet of a structure but not near a viable anchor point on City property (weed abatement areas #1, #3, #5, and #10). Instead, the nearest or most efficient anchor points for a weed abatement area may be located on private property, under HOA management, or with another agency.

In the City's vegetation management program, the majority of weed abatement areas consist of a strip of open space adjacent to developed private properties (Weed Abatement Areas #1, 3-11). Each of these weed abatement areas should begin and end at a good anchor point. Six of the weed abatement areas are anchored to features that a fire would not be expected to spread around, while five are unanchored. For the five weed abatement areas without anchor points, the maintained area includes the entire portion within 100 feet of the City open space where a structure is located. None of these five areas has a good anchor point on City-owned property within 100 feet of the weed abatement area. In order to establish a viable anchor point, the City should work collaboratively with private property owners to expand fuel breaks (see Table G-3 in Appendix G).

Goat Grazing
Given the complex ownership structure of open space areas in Laguna Niguel, many residents and community members may not be aware of their responsibilities regarding open space management. As such, implementing a targeted goat grazing program offers a practical and visible approach to weed abatement that not only enhances fuel management but also raises community awareness of proactive wildfire prevention efforts. By deploying goats in a highly visible and strategically prioritized location, the City can demonstrate tangible steps toward reducing wildfire risk while educating residents about the importance of vegetation management and defensible space.

Utilization of this strategy reinforces shared responsibility among homeowners' associations, public agencies, and private landowners. Over time, this strategy can help build community engagement and foster a culture of preparedness amid increasing fire risk.

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CEQA Analysis
Avoiding Impacts and Best Management Practices
The City's current vegetation management program and the recommendations in this report are not considered to have a significant impact on the environment according to CEQA. However, we recommend that the City implement the best practices described in this section. These recommendations, including our recommendation to conduct a desktop analysis of biological and cultural resources, are useful for informing the City about any protected resources in the managed areas and can support the preparation of the Notice of Exemption (NOE).

Based on our experience with fuel reduction and vegetation management projects elsewhere in Southern California, the following CEQA impact categories are most likely to be considered when conducting vegetation management activities.
• Biological Resources
• Cultural Resources
• Hydrology and Water Quality
• Geology and Soils
Below are recommended practices for the City to apply to its vegetation management program to both minimize environmental risk and support the preparation of a CEQA document.

Biological Resources
To assess biological resources and potential constraints, review relevant literature and data on sensitive habitats and species distributions to identify resources that may occur within the study area. The literature and database review can include data from the following sources:
• CDFW California Natural Diversity Database (CDFW 2025) • California Native Plant Society Inventory of Rare and Endangered Plants (CNPS 2025) • USFWS Critical Habitat and Occurrence Database (USFWS 2025a) • U.S. Department of Agriculture Natural Resources Conservation Service Web Soil Survey (USDA, 2025) • Google Earth (2025)
• USFWS National Wetlands Inventory (USFWS 2025b)
• USGS National Hydrography Dataset (USGS, 2025)
The existing weed abatement areas have been managed for an extended period of time and are primarily covered with non-native vegetation. It is unlikely that any sensitive biological resources would be present in a highly disturbed habitat. In the unlikely event that a protected biological resource is determined to have a high potential to occur within the vegetation management program area, the City could work with a qualified biologist to determine management practices to minimize impacts.

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Cultural Resources
Conduct a records search at the South Coastal Information Center (SCIC). The records search involves a review of pertinent SCIC base maps that reference cultural resources records and reports, historic-period maps, and literature for the vegetation management program area. The SCIC also provided shapefiles of the locations of previously recorded cultural resources and previous investigations. Additional information regarding cultural resources in the City can be found in the following literature and maps. ■ The California Register of ■ Historic Maps
Historical Resources ■ National Register of Historic Places ■ California Place Names ■ Handbook of North American Indians, ■ California State Historical Landmarks Volume 8: California ■ General Land Office Plats ■ Historic Spots in California ■ California State Points of Historical Interest
In the unlikely event that cultural resources are determined to have a high potential to occur within the vegetation management program area, the City could work with a qualified archeologist to mark off areas to avoid and determine management practices to minimize impacts.

Hydrology and Water Quality
The City's current vegetation management practices are unlikely to impact hydrology and water quality in City-owned open space areas because the current practices do not involve any excavation or significant soil disturbance, and are not near any waterways or riparian areas. Impacts to hydrology and water quality can be further minimized by following Orange County water quality BMPs, including avoiding performing vegetation management work when rain is likely to occur or when soils are saturated.

Geology and Soil
Like hydrology and water quality, the City's current vegetation management practices are unlikely to impact geology and soils in the City-owned open space areas because the current practices do not involve any excavation or significant soil disturbance, and are not near any waterways or riparian areas. Impacts to hydrology and water quality can be further minimized by following Orange County water quality BMPs, including:
• Avoid performing vegetation management work when rain is likely to occur or when soils are saturated. • Leaving stumps and below-ground portions of cut vegetation intact.

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Findings and Recommendations
Dudek's analysis of the City's current vegetation management program determined that the City of Laguna Niguel is meeting the regulatory requirements for creating defensible space on the portions of City-owned open space that are within 100 feet of a structure, and meeting the standards published by OCFA for how vegetation in this 100- foot area is to be maintained. Based on our analysis, Dudek is making the following four recommendations to further enhance the City's defensible space and vegetation management program:

Category Recommendation
Weed Abatement 1) While not mandated by state law nor local regulations, Dudek recommends adding the Southwest corner of Salt Creek Corridor near Niguel Road to the City's weed abatement program (Opportunity Area A).
2) Modify the weed abatement strategy used in weed abatement area #6 (Reef View Node: 2.6 acres) from hand crews to goat grazing to increase community awareness on wildfire prevention and weed abatement strategies.

Vegetation Management 3) Coordinate vegetation management timing, access, and standards with adjacent HOAs, homeowners, and other agencies to ensure the full defensible space area is maintained.

CEQA 4) File a CEQA Notice of Exemption (NOE) for implementation of best management practices (BMPs) for biological resources, cultural resources, hydrology/ water quality, and soils.

The remainder of this section describes our recommendations for addressing these findings, including enhancements to the City's existing vegetation management program and working with adjacent property owners and managers to further mitigate fire risk on their properties.

Recommendation #1 - Southwest Salt Creek Corridor (Opportunity Area A) Based on our analysis of areas where regulations and anticipated fire behavior require vegetation management, Dudek recommends adding Weed Abatement Opportunity Area A to modify the vegetation management program in City open space, improving fire safety and reducing the risk of structure ignition near open space areas. While not required by state law or local regulations, adding Opportunity Area A is consistent with the City's existing practices.

Weed Abatement Opportunity Area A, shown in Figure 10, is up to 1.6 acres recommended to be included in the City's vegetation management plan. These 1.6 acres are located in the southwest corner of the Salt Creek Corridor Open Space near Niguel Road. This additional area covers the hillsides behind the homes and structures at the ends of Champany Place, Coplay Place, Ticknor Place, and Rollins Place. There is an approximately 0.5-acre area behind the homes at the ends of these streets, which is on City-owned open space and within 100 feet of a structure. This 0.5-acre is divided into three separate strips, and the additional 1.1 acres provide continuity between the three separate strips as well as anchoring this additional area on the northeast side to the private park on Beacon Hill Road. There is no suitable anchor point on City-owned property on the west end of this additional area.

In total, Dudek's recommendations would add 1.6 acres to the vegetation management program.

The management of vegetation in Opportunity Area A should be completed in accordance with OCFA requirements through either one of the following:

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1. The City incorporates Weed Abatement Opportunity Area A into the existing weed abatement program.

2. The City works with the adjacent HOA and private property to incorporate Weed Abatement Opportunity Area A into their existing landscape maintenance program.

Implementation and Prioritization
Given the proactive approach taken by City Staff, the City can complete vegetation management in the City's open space, including the 44 acres in the existing weed abatement program, prior to the onset of peak summer conditions (July). Since this work will be completed before peak summer conditions, which is the preferred timing, there is no immediate need to modify treatment schedules to prioritize certain areas for treatment. Annual grasslands are the predominant vegetation cover in the weed abatement areas, and treatment of these areas needs to occur after the grass cures, which limits the importance of prioritizing one area over another. Instead, it would be more efficient (e.g., reducing the need to revisit sites) and beneficial for fire safety to ensure that vegetation management in the annual grasslands is properly timed. Additionally, City staff are proactively working with OCFA and the HOA in Opportunity Area A to implement the recommended supplemental weed abatement consistent with the City's existing practices and in alignment with OCFA regulations.

Recommendation #2 - Weed Abatement: Goat Grazing at Reef View Node Based on our analysis of expected fire behavior in City open space areas and observations from field visits, the vegetation management practices currently utilized by the City, including methods and timing, are well-suited to the terrain and vegetation in the areas described in this report. As a strategy to increase community awareness of wildfire prevention, Dudek recommends that the City transition from traditional hand-crew weed abatement strategies to implementing goat grazing at the Reef View Node.

Goat grazing is an effective and highly visible weed abatement strategy that not only reduces hazardous vegetation but also serves as a powerful tool for increasing community awareness of wildfire prevention. Unlike traditional methods, goat grazing draws public attention and naturally sparks curiosity, creating opportunities for outreach and education about the link between dry vegetation and wildfire risk. As residents observe goats clearing brush in open spaces and near neighborhoods, they gain a tangible understanding of fuel reduction and the importance of maintaining defensible space. This visibility encourages community members to reflect on their own roles in fire prevention, promoting shared responsibility and proactive behavior in compliance with fire safety guidelines.

Additionally, goat grazing enhances public acceptance and engagement with wildfire mitigation efforts. Over time, these programs help foster a culture of awareness and preparedness, making wildfire prevention a more understood and supported priority within the community.

Recommendation #3 - Vegetation Management Coordination
Defensible space around structures in high wildfire-risk areas, such as the VHFHSZ, is not an 'every little bit helps' approach (NIST, 2022). In these areas, wildfire risk to a structure is only significantly reduced when the entire defensible space area is maintained to the OCFA's guidelines; when not maintained to the OCFA's guidelines, there remain fuels near the structure that can ignite or pathways for the fire to spread to the structure. Given the complex land ownership in the City's open space areas, responsibility for ensuring that the entire defensible space area is compliant lies with the HOAs, County agencies, utilities, private homeowners, and the City. This complexity continues DUDEK 27
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down to the individual structure, where the maintenance of the vegetation in the 100-foot area may be the responsibility of the homeowner, HOA, and the City.

Wherever the City shares responsibility for vegetation management with an adjacent property, there is a need for the City to collaborate with the adjacent property owner to ensure that vegetation management is performed in a complementary fashion according to OCFA's guidelines. The complex ownership of open space in the City also limits the City's ability to anchor its weed abatement areas to features that fire cannot spread around and to break up continuous strips of hillside that the City maintains. Several weed abatement areas (weed abatement areas #1, 3-4, and 9-10) begin and end at a property line and are not anchored to a feature that a fire could not spread around.

Partnering with adjacent property owners here is important to ensure that the areas managed by the City do not end abruptly but continue onto adjacent property, either to a viable anchor point or another vegetation treatment area.

Dudek recognizes that merely recommending that the City or OCFA enfo rce defensible space guidelines is not a sustainable approach and does not reflect a collaborative strategy to reduce wildfire risk. The City currently engages with property owners and HOA board members through its HOA Education Program (City of Laguna Niguel 2026).

Additionally, there are five active FireWise Communities in the City (NFPA 2026). The City has, for the past several years, taken steps to collaborate with HOAs and private property owners on wildfire preparedness, including defensible space and vegetation management. The City's current level of engagement includes:

1. Preparing wildfire mitigation articles for the City's HOA Quarterly newslett er.

2. Preparing and giving a vegetation management presentation at HOA Education meetings prior to the start of peak summer conditions.

3. Providing courtesy notices to HOAs and adjacent property owners about areas on their property that need additiona I vegetation management.

4. Working with Laguna Niguel Communities to apply for grant funding for fuel break projects on HOA and City open space areas.

5. Partnering with OCFA and HOA groups to conduct a home assessment at a property adjacent to City open space (OCFA off ers these for free) as an opportunity to educate HOAs and property owners on defensible space requirements and the OCFA's guidelines.

Building on the City's and community's existing programs, we recommend the following additional activities:

1. Continue coordinating hillside vegetation management activities with neighboring HOAs in City open space areas so that crews are treating the entire defensible area at the same time and can use the same access points.

2. Meet with HOAs that share responsibility with the City for maintaining defensible space requirements, and develop a vegetation management plan that creates connectivity between City-maintained areas, HOA­ maintained areas, and good anchor points (see Table G-4 in Appendix G).

3. Work with OCFA Community Risk Reduction staff to earn state-level recognition on the Fire Risk Reduction Community List as identified in the City's adopted Strategic Plan.

Recommendation #4 - CEQA Review
The activities evaluated in the City's Defensible Space and Management Program do not involve land use changes, expansion of existing facilities, grading, or removal of healthy, mature, or scenic trees. Vegetation management is DUDEK 28
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limited to fuel reduction and maintenance activities intended to reduce wildfire intensity and structure ignition potential, generally within 100 feet of structures, and does not involve soil excavation or grade changes.

Accordingly, the program qualifies for exemption from the California Environmental Quality Act (CEQA), as summarized below.

Categorical Exemptions (CEOA Guidelines, Title 14 CCR)
• Class 1 - Existing Facilities (§15301): The vegetation management activities constitute routine maintenance of existing public facilities, including City-owned open space, parks, trails, landscaped slopes, and rights-of-way. The program does not expand facility use or increase the intensity of operations and represents ongoing maintenance consistent with long-standing municipal practice. Activities fall within §15301(h), which applies to maintenance of existing public facilities involving negligible or no expansion of use.
• Class 4 - Minor Alterations to Land (§15304): The program involves minor alterations to vegetation and land that do not result in significant environmental effects. This exemption expressly includes fuel management activities within 30 feet of structures, or up to 100 feet where required by the fire authority having jurisdiction. Vegetation treatments are limited in scope and do not involve substantial ground disturbance.
• Class 7 - Actions by Regulatory Agencies for Protection of Natural Resources (§15307): Vegetation management activities reduce wildfire risk and protect natural resources by minimizing the potential for catastrophic fire impacts to habitat, watersheds, and preserved open space areas. • Class 8 - Actions by Regulatory Agencies for Protection of the Environment (§15308): The program reduces environmental hazards by mitigating wildfire risk and protecting surrounding communities and environmental resources from the effects of uncontrolled wildfire behavior.

Statutory Exemptions (Public Resources Code §21080)
• Ongoing Project Exemption (§15261): · The City's vegetation management activities represent a continuation of a long-standing municipal program that has been implemented consistently over time without substantial change in scope or intensity.
• SB 131 - Wildfire Risk Reduction Exemptions (Effective June 30, 2025): Senate Bill 131 expanded and clarified CEQA statutory exemptions applicable to wildfire risk-reduction activities, including defensible space, fuel breaks, and vegetation treatment undertaken for public safety purposes. These provisions further support the City's reliance on CEQA exemptions for the vegetation management activities evaluated in this report.
• Governor's Proclamation of a State of Emergency-(Effective March 1, 2025): Governor Newsom's proclamation suspends the California Environmental Quality Act (Division 13 (commencing with section 21000) of the Public Resources Code and regulations adopted pursuant to that Division) and the California Coastal Act (Division 20 of the Public Resources Code, commencing with section 30000, and regulations adopted pursuant to that Division) to the extent necessary for expediting critical fuels reduction projects that include as a primary objective at least one of the following activities:

Removal of hazardous, dead, and/ or dying trees;
Removal of vegetation for the creation of strategic fuel breaks as identified by approved fire prevention plans, including, without limitation, CAL FIRE Unit Fire Plans or Community Wildfire Preparedness Plans; DUDEK 29
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Removal of vegetation for community defensible space;
Removal of vegetation along roadways, highways, and freeways for the creation of safer ingress and egress routes for the public and responders, and to reduce roadside ignitions. Removal of vegetation using cultural traditional ecological knowledge for cultural burning and/ or prescribed fire treatments for fuel reduction.

Numerous jurisdictions within Orange County implement annual weed abatement and vegetation management programs of similar scope. Several cities- including Irvine and Mission Viejo- have relied on Class 4 (Minor Alterations to Land) exemptions and, in many cases, have documented those determinations by filing a Notice of Exemption (NOE). While program scope, administration, and documentation practices vary by jurisdiction, the use of categorical exemptions for defensible-space and vegetation-management programs is common and well established.

Although preparation and filing of an NOE is not always the local or industry standard practice for routine vegetation management activities, the safest and most conservative approach for the City of Laguna Niguel would be to file an NOE documenting its CEQA determination. Filing an NOE provides a clear administrative record, formally documents the City's reliance on applicable categorical and statutory exemptions, and establishes the statute of limitations for potential CEQA challenges. This approach is particularly appropriate given the program's recurring, multi-year nature, its implementation adjacent to residential development, and its location within State-designated Fire Hazard Severity Zones. Filing an NOE does not mean that formal CEQA environmental review is required; instead, it reflects a conservative documentation strategy that may be supported by a desktop-level environmental review to substantiate the City's reliance on CEQA exemptions.

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Conclusion
The City of Laguna Niguel's existing Vegetation Management Program on City-owned open space lands provides an effective level of wildfire risk reduction for the communities adjacent to City-owned open space areas. Based on review of the regulations pertaining to vegetation management and defensible space, wildfire behavior modeling, field observations, and a cost-effectiveness analysis, the City is meeting state and local defensible-space requirements and is maintaining vegetation within City ownership in a manner consistent and in compliance with Orange County Fire Authority (OCFA) guidelines.

Wildfire modeling conducted for this assessment demonstrates that vegetation management within the existing 100-foot defensible space areas substantially reduces flame lengths and fire intensity under both typical fire-season conditions and extreme Santa Ana wind scenarios. In the predominant vegetation types present within City-owned open space- annual grasslands and coastal sage scrub- the current width and maintenance standards of the City's weed abatement areas are sufficient to reduce modeled flame lengths to levels that significantly lower the likelihood of direct flame contact with nearby structures. As such. the City's program effectively fulfills its primary objective of reducing wildfire risk to the community in most cases by minimizing the potential for structure ignition from wildfires originating in adjacent open space.

While the City's program is largely effective, this report identifies targeted opportunities for improvement. A small area (0.5 acres) of City-owned open space within the southwest corner of the Salt Creek Corridor, near Niguel Boulevard, is within 100 feet of nearby structures on Coplay, Tiknor, and Rollins Place and is not currently included in the vegetation management program (Opportunity Area A). This area should be considered for addition to ensure continuity of defensible space. With minor refinements to newly identified hazards, the City can continue to be an exemplary agency.

While existing vegetation management practices are appropriately tailored to the City's open space conditions and effectively address fire behavior concerns, there is an opportunity to enhance community engagement in wildfire prevention efforts. Based on field observations and analysis, transitioning from traditional hand crew weed abatement to goat grazing at Reef View Node is recommended as a strategic enhancement. Goat grazing not only reduces hazardous vegetation but also serves as a highly visible and engaging method that raises public awareness of wildfire prevention and weed abatement activities.

A key finding of this assessment is that the effectiveness of the City's vegetation management program is strongly influenced by conditions on adjacent private properties. Since wildfire spreads across landscapes rather than parcel boundaries, defensible space on City-owned land is most effective when it is continuous and connected to vegetation management performed by homeowners, homeowners' associations, and other public agencies. In locations where City-maintained areas end abruptly at property lines without anchoring to another treated area or non-burnable feature, wildfire may bypass managed vegetation and continue toward structures. For this reason, continued collaboration with adjacent property owners/ managers is essential to maximizing risk reduction.

Accordingly, long-term wildfire resilience in Laguna Niguel will depend not only on the City continuing its vegetation management in its open-space areas but also on sustained coordination among the City, OCFA, HOAs, and private property owners. Expanding education, coordination, and joint treatment efforts, particularly in shared defensible-space zones and along community perimeters, will further enhance the effectiveness of existing DUDEK 31
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treatments and help ensure that wildfire risk is addressed comprehensively rather than in isolated fragments, based upon land ownership.

Regarding CEQA and the need to prepare and submit CEQA documentation for the City's vegetation management program. It is not common practice for nearby municipalities or counties to prepare CEQA documents for vegetation management projects intended to maintain vegetation in the defensible space area near structures. However, it is our conclusion that the vegetation management activities evaluated in this report qualify for applicable CEQA exemptions as routine maintenance and wildfire risk-reduction measures and that a Notice of Exemption will satisfy the documentation requirements. With the implementation of recommended best management practices and appropriate documentation, the City can both continue to carry out a vegetation management program that is eff ective at reducing fire risk and, at the same time, avoid stripping the hillsides of vegetation and thereby minimizing the risk of erosion and run-off , avoiding any impact on sensitive biological communities present.

Overall, the City of Laguna Niguel's Defensible Space and Vegetation Management Program represents an effective, technically supported approach to reducing wildfire risk to the communities surrounding its open spaces. With minor refinements and increased cross-jurisdictional coordination, the program can continue to play a vital role in protecting life, property, and community assets in the face of increasing wildfi re hazards.

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Accessed on February 26, 2026, at www.ocfa.org/ RSG
Orange County Fire Authority. (n.d.). Ready, set, go! Retrieved March 11, 2026, from https/ / ocfa.org/ ready-set-go/
Orange County Fire Authority. (n.d.). Vegetation management. https:/ / ocfa.org/ready-set-go/ vegetation-ma nagement/
Ott, Jeffrey E., Francis F. Kilkenny, & Theresa B. Jain. (2023). Fuel treatment effectiveness at the landscape scale:
a systematic review of simulation studies comparing treatment scenarios in North America. Location:

USDA Forest Service Rocky Mountain Research Station. February 20, 2023. Accessed on March 11, 2026. file:/// P:/320.Urba n Forestry/ 19066_Laguna%20N iguel%20D-Space%20and%20VM P%20study / 06%20References/ s42408-022-00163-2.pdf
Rothermel, R. C. (1983). How to predict the spread and intensity of forest and range fires. GTR INT-143. Ogden, Utah:

USDA Forest Service lntermountain Research Station.161 Rothermel, R.C., and G.C. Rinehart. 1983. "Field procedures for verification and adjustment of fire behavior predictions." Res. Pap. INT-142. Ogden, UT: U.S.

Department of Agriculture, Forest Service, lntermountain Forest and Range Experiment Station. 25 p.

Sugihara, N. G., Van Wagtendonk, J. W., Fites-Kaufman, J., Shaffer, K. E., & Thode, A. E. (2006). Fire in California's ecosystems. University of California Press.

U.S. Department of Agriculture, Natural Resources Conservation Service. (2022, November). Conservation Practice Standard: Firebreak (Code 394). https:/ / www.nrcs.usda.gov/ U.S. Forest Service. (n.d.). *FireNet glossary*. lnteragency Fuel Treatment Decision Support System. https:// iftdss. firenet.gov / fi renetHelp/ help/ pageHel p/ content/ 41-references/ glossa ry.htm Weather Spark. (2026). Climate and Average Weather Year-Round in Laguna Niguel. Accessed March 2026. https/ / weatherspa rk.com/ y / 1861/ Average-Weather-in-Laguha-N iguel-Ca I iforn ia-U n ited-States-Yea r­ Rou nd#google _ vignette
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Appendix A
Acronyms and Abbreviations

APPENDIX A / ACRO NYMS AND ABBREVIATIO NS
Acro nym/ Abbreviat ion Definit ion
CEQA California Environmental Quality Act
City The City of Laguna Niguel
County Orange County
FHSZ Fire Hazard Severity Zone
HFHSZ High Fire Hazard Severity Zone
HOA Homeowners Association
OCFA Orange County Fire Authority
VHFHSZ Very High Fire Hazard Severity Zone
WUI Wildland Urban Interface
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INTENTIONALLY LEFT BLANK
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Appendix B
List of Key Terms with Definitions

APPENDIX B / LIST OF KEY TERMS WITH DEFINITIONS
This document contains terms used by wildfire scientists to describe conditions that influence wildfire spread, growth, and behavior. Additionally, this document contains terms used by fire departments to describe recommended and required fire prevention activities. These terms are defined below for the reference of this document's readers.

Crown Fire: A fire that advances from top to top of trees or shrubs more or less independent of a surface fire. Crown fires are sometimes classed as running or dependent to distinguish the degree of independence from the surface fire (NWCG n.d.).

Defensible Space: Defensible space is an area between your house and an oncoming wildfire, where the vegetation has been controlled, trimmed, or removed to reduce wildfire threat from embers and intense heat. (0CFA 2026). 0CFA's defensible space guidelines divide the defensible space area into four Zones (Section 3.1) depending on the distance from the structure.

Fire Break: A permanent or temporary strip of ground cleared to bare soil or planted with fire-resistant vegetation meant to stop the spread of fire (USDA NRCS 2022).

Fuel Break: Fuel breaks are strategically located zones, often along ridgelines, roads, or community perimeters, where vegetation has been modified, reduced, or removed to slow fire spread, reduce flame length, and provide a safe and effective area for fire suppression activities (CAL FIRE, 2019).

Fuel Modification/ Fuel Reduction Area: A strip of land where combustible vegetation has been thinned or modified, or both, and may be partially or totally replaced with approved fire-smart or irrigated plants, or both, to provide an acceptable level of risk from vegetation fires. Fuel modification reduces the radiant and convective heat on a structure and provides valuable defensible space for firefighters to make an effective stand against an approaching fire front (City of San Diego 2026).

Gridded Winds: Gridded winds are modeled winds using computational models to account for the influence of topography on wind speed and direction. Without gridded winds, every cell on the landscape will have the same wind speed and direction. Proper use of gridded winds in an analysis can produce more realistic fire behavior modeling results (IFTDSS n.d.).

Herbaceous Vegetation: A plant that does not develop woody, persistent tissue but is relatively soft or succulent and sprouts from the base (perennials) or develops from seed (annuals) each year. Includes grasses, forbs, and ferns (IFTDSS n.d.).

Riparian Vegetation: Plant communities contiguous to and affected by surface and subsurface hydrologic features of perennial and intermittent lotic and lentic water bodies such as rivers, streams, lakes, or drainage ways. Riparian areas have one or both of the following characteristics: 1) distinctly different vegetative species from adjacent areas, and 2) species similar to adjacent areas but exhibiting more vigorous or robust growth forms. Riparian areas are usually transitional between wetland and upland habitats (USFWS/ National Wetlands Inventory 1997) Structure: That which is built or constructed (ICC, 2025). A structure can include buildings intended for occupancy by people or for equipment only.

Vegetation Management: Vegetation Management is the controlling of plant materials to prevent wildfire spread (0CFA 2026).

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APPENDIX B / LIST OF KEY TERMS WITH DEFINITIO NS
Weed Abatement Area: One of 11 City-owned and maintained open spaces, covering 44 acres of land on which the Public Works Department provides yearly weed abatement services. This program is designed to meet the Orange County Fire Authority (OCFA) standards by reducing fire hazards (City of Laguna Niguel 2026) DUDEK B-2
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Appendix C
Assessment Methodology

LAGUNA NIGUEL DEFENSIBLE SPACE AND VEGETATION
MANAGEMENT PROGRAM STUDY: METHODOLOGY
Dudek is assisting the City of Laguna Niguel (the City) in assessing its current weed abatement and vegetation management practices for City-owned open spaces, and in evaluating both the benefits and constraints of expanding beyond the existing Orange County Fire Authority (OCFA) defensible space requirements of 100 feet.

This document outlines Dudek's proposed methods for conducting this assessment, which are organized into three components: a wildfire risk assessment, a vegetation management program effectiveness assessment, and a CEQA analysis. Together, these sections establish a comprehensive framework for evaluating wildfire risk, regulatory compliance, and environmental considerations. The methodology integrates regulatory standards, spatial data analysis, and predictive fire behavior modeling to identify high-risk areas, assess current vegetation management performance, and inform potential future program improvements that enhance community wildfire resilience. In addition, this methodology is intended to be dynamic and adaptive, allowing for updates as new data, field conditions, and agency guidance inform future decisions.

1. Wildfire Risk Assessment

1.1 Preliminary Open Space Review
A preliminary review will be conducted of all City-owned open space areas to identify the specific City-owned open space parcels where vegetation management is either required by OCFA or where it would be beneficial to include in a vegetation management program to reduce wildfire risk to nearby structures and critical infrastructure.

The preliminary review will consist of creating a GIS layer overlaid on the existing City parcel map and structure footprint layers and drawing a buffer that starts at the edge of structures abutting open space areas and extends horizontally to a minimum of 100 feet. Dudek will record the city-owned open space parcels that intersect with this buffer as open space areas for inclusion in the comprehensive wildfire risk assessment. The 100-foot minimum buffer is based on the following:
• The fuel modification distance OCFA requires in their vegetation management guidelines • Maximum anticipated flame lengths based on the existing vegetation cover and terrain, based on preliminary fire behavior modeling.

This 100-foot buffer will capture all open space parcels that require vegetation management under OCFA guidelines.

Open space lands outside the 100-foot-wide buffer will also be assessed for their potential to result in wildfire spread towards communities, and to ensure that assessment includes any fire hazards beyond the 100-foot area that could threaten nearby structures.

1.2 Regulatory Assessment
Dudek will review the City's and the county's regulations and standards applicable to the City's vegetation management program. These include guidelines, regulations, and standards for defensible space, fuel modification, and vegetation management from local fire agencies, as well as erosion/ run-off prevention best management DUDEK [MONTH YEAR]

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practices and guidelines published by the City and county. Dudek will summarize the best management practices, guidelines, regulations, and standards that are applicable to the Project. This summary will be used during the wildfire risk assessment to identify and distinguish open space areas that meet vegetation management requirements and where constraints, such as excessive runoff, may occur. The summary will also be used later during the assessment of the current vegetation management as the baseline for effective vegetation management.

Dudek will review best management practices, guidelines, regulations, and standards from the following sources. • OCFA Guidelines
• California Fire Code
• Laguna Niguel Best Management Practices for Stormwater Control and Erosion Prevention. • Government Code 51182
• Section. 8-1-1301 of the Laguna Niguel Municipal Code and California Wildland Urban Interface Code The purpose of this review is to identify the regulatory requirements that specify the required defensible space and vegetation management treatment distance requirements, as well as the specific vegetation treatment standards regarding clearance between buildings and vegetation, vegetation spacing, and trimming. This analysis would incorporate the Orange County Fire Authority (OCFA) Fuel Modification Standards (Guideline C-05) and defensible space requirements, which establish the extent of vegetation treatment areas adjacent to development and serve as the referenced guidance for vegetation management standards in the City's municipal code. The results of this analysis will inform the fire environment assessment and justify current and recommended vegetation management practices.

1.3 Fire Environment Assessment in Laguna Niguel Open Space According to the National Wildfire Coordinating Group (NWCG), the fire environment is defined as "The surrounding conditions, influences, and modifying forces of topography, fuels, and weather that determine wildfire behavior." The fire environment for this analysis will be described by topography, vegetation (fuel types and continuity), weather patterns, and built-environment features that influence wildfire ignition potential and spread.

A comprehensive analysis of City-maintained and publicly available datasets will be conducted to characterize the fire environment, identify conditions that influence wildfire behavior and exposure in City-owned open spaces, and assess potential impacts on City-owned improvements, adjacent infrastructure, and buildings. Key elements will include:
• Fuel characteristics such as vegetation type, condition, and arrangement. • Topographic influences, including slope, aspect, and elevation. • Historical topographical slope movements, expansive/ subsidence soils maps, and landslide seismic hazard zone maps
• Historical and climatic weather conditions affecting fire intensity and spread. • Historical wildfires in similar terrain and fuels in the City and surrounding area. • Proximity to structures, access roads, and infrastructure, which modify exposure and suppression capability.
• Fire Hazard Severity Zone and Wild land Urban Interface Maps.

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Determining the fire environment will support the identification of high-risk areas and inform fire behavior modeling and prioritization of fire management.

1.4 Analysis of City and Publicly Available Datasets
This section will identify and describe the data used to characterize the City's wildfire environment and evaluate vegetation management needs. It will also summarize how these datasets are used in GIS analysis and subsequent modeling.

City Datasets
• Open Space, Ownership, HOA Boundaries: City and regional mapping data will be used to identify the boundaries, ownership, and management responsibilities of open space parcels throughout the City. This includes determining whether areas are owned or maintained by the City, homeowners' associations (HOAs), private entities, or other public entities. Understanding how these boundaries connect helps clarify vegetation management responsibilities and ensures that fuel reduction efforts are consistent with OCFA guidelines and create continuous areas of treated vegetation across property lines, particularly where City open space borders residential communities.
• Open Space Access or Service Road Routes Documents: Existing maps/ documents/ images of open space access roads, trails, and service routes will be reviewed to evaluate how easily maintenance crews and fire personnel can reach different areas. Assessing the condition and connectivity of these roads also helps identify opportunities to use them as access points or secondary fire breaks during wildfire response. • Existing Environmental Reports: Environmental documents such as Environmental Impact Reports (EIRs), biological resource assessments, and geotechnical studies will be reviewed to identify any site constraints that may affect vegetation management. This includes areas with sensitive habitat, steep slopes, or erosion concerns where fuel treatment methods may need to be adjusted. • Existing Weed Abatement or Vegetation Management Program Areas: Information on the City's existing weed abatement and vegetation management programs will be compiled to understand where treatments are already taking place. Mapping these areas will help identify maintenance gaps, overlapping responsibilities, and opportunities to coordinate future vegetation management activities more efficiently.

Public Datasets
• Structure Footprints: Publicly available building footprint data will be used to map the location and density of structures across the City. This information provides the basis for creating defensible space buffers and assessing the proximity of buildings to wild land fuels. • Fire History: From CAL FIRE Fire Resource and Assessment Program (FRAP) and OCFA Open Data Hub, previous fire perimeters would aid the team in analyzing the frequency, size, and cause of historical fires affecting or near the City. This would provide insight into what areas to prioritize for ignition resistance.

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• Fire Hazard Severity Zone Maps: CAL FIRE's Fire Hazard Severity Zone (FHSZ) maps for both State and Local Responsibility Areas will be reviewed to classify open space parcels by hazard tier (Moderate, High, or Very High). These classifications will be integrated with City parcel data to map wildfire hazard exposure boundaries and identify priority areas for vegetation management. • Vegetation Maps: Vegetation data from the Orange County 2022-2025 Orange County Fine-Scale Vegetation Map and supplemental datasets and satellite imagery will be used to characterize the types and density of fuels throughout the City at a 10-m resolution. Understanding vegetation structure and continuity will help determine where fuel reduction treatments are most needed while maintaining consistency with habitat protection goals.
• Topographic Maps: Topographic and elevation data from USGS and local GIS sources will be used to evaluate slopes, aspects, and terrain features that influence fire behavior. This information helps identify areas where steep slopes or ridgelines may increase fire intensity or complicate access for maintenance and emergency response.

After compiling the datasets above, the information will be integrated into GIS for spatial analysis. A 100-foot buffer will be established around all structures consistent with the OCFA defensible space standards. This buffer will be overlaid with City-owned open space boundaries, vegetation types, and slope data to identify where vegetation management may be performed and would be beneficial. These results will provide the foundation for wildfire behavior modeling.

1.5 Wildfire Behavior Modeling
Following the completion of Section 1.1, wildfire behavior modeling will be conducted to evaluate anticipated fire behavior in City-owned open spaces within the 100-foot buffer. The modeling will provide a quantitative foundation for identifying wildfire risk zones, estimating potential flame lengths and rates of spread, and prioritizing areas for vegetation management and fuel reduction. Open space lands outside the 100-foot-wide buffer will also be modeled for their potential to result in wildfire spread towards communities in areas where there is a unique fire risk, as identified by the City or areas observed during the field visit (Task 1. 7).

Model inputs will include topography, vegetation (fuel types, loading, and continuity), weather parameters, and other factors that influence fire behavior. The analysis will be completed using the Flam map fire modeling software package, which integrates spatial data and predictive fire behavior models to simulate how fires may behave under various environmental conditions.

Areas of focus for the modeling effort will include the following components:

Quantitative Risk Analysis
This modeling framework estimates overall wildfire risk to buildings.1 By combining factors such as vegetation, slope, weather, and fire history. It calculates where fires are most likely to start and where they could be most severe.

Comparing current conditions to proposed vegetation management scenarios helps determine how much each treatment would reduce potential fire intensity and spread. 1 2025 California Fire Code defines a building as any structure utilized or intended for supporting or sheltering any occupancy.

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Burn Probability
Burn probability modeling in Flam map predicts how likely different parts of the landscape are to burn under a range of weather and ignition conditions. Using historical fire data and wind patterns, the model generates maps showing which areas are most likely to burn. These results help the City focus vegetation management on areas with the greatest probability of fire exposure.

Landscape Fire Behavior
Landscape fire behavior modeling uses Flammap to estimate expected flame lengths, fireline intensity, and rate of spread across the City's open space areas. The model is run under both current and post-treatment conditions to show how vegetation management would change potential fire behavior. In addition, since the City is at risk from both summer and high wind event weather conditions, landscape fire behavior will be modeled under two weather scenarios and aggregated to provide a weighted estimate of wildfire behavior. Further, fire behavior modeling will account for existing fuel management areas. The resulting maps and data will be a tool for future planning and help the City prioritize open space areas for ongoing fuel reduction and maintenance.

1.6 Fire Hazard Versus Fire Risk
Fire hazard is not the same as fire risk.2. CAL FIRE designates fire hazards and maps these areas where there is an elevated fire hazard. These mapped areas include the areas where there is a regulatory requirement to maintain defensible space. However, wildfires can occur on any site, inside or outside the designated areas, when conditions allow their spread. The purpose of this task in the fire assessment is to categorize and understand the relationship between open space lands where vegetation management is required by regulation and where there is a benefit to performing vegetation management because of the increased fire safety.

As part of the assessment of the fire environment in city-owned spaces, Dudek will map and compare the extent of areas within a CAL FIRE fire hazard severity zone with those identified in wildfire behavior modeling as having high fire risk, high burn probability, and high-intensity fire behavior. This comparison will be performed using the fire hazard severity zone, quantitative risk analysis, burn probability, and landscape fire behavior GIS layers made during the tasks described above. These layers will be overlaid to allow the comparison. Then, an output layer will be created that shows the areas where both the wildfire behavior modeling and the fire hazard severity zone maps indicate potential wildfire. The results of this analysis will be used later during the development of the vegetation management recommendations to determine the areas where there is a regulatory requirement to maintain vegetation and where fire risk indicates a benefit to performing vegetation management.

1. 7 Field Verification
To confirm that the modeled results accurately reflect on-the-ground conditions, the project team will conduct field verification after completing the wildfire behavior modeling. This effort will include site visits by the Dudek team to review existing vegetation-treatment areas, verify fuel types and conditions, and inspect locations identified during the wildfire modeling process as having elevated fire risk. Field verification ensures that the data used in GIS and 2 CAL FIRE describes the difference as ""Hazard" is based on the physical conditions that create a likelihood and expected fire behavior over a 30 to 50-year period without considering mitigation measures such as home hardening, recent wildfire, or fuel reduction efforts. "Risk" is the potential damage a fire can do to the area under existing conditions, accounting for any modifications such as fuel reduction projects, defensible space, and ignition resistant building construction. " DUDEK DECEMBER 2025 5

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fire behavior modeling aligns with actual site conditions. It also provides an opportunity to confirm wildfire behavior outputs, identify unique fire hazards, and document existing fire breaks or barriers that could influence fire spread.

1.8 Web-based GIS Mapping Tool
Upon completion of the wildfire hazard and risk assessment, the analysis results will be delivered through a web­ based GIS platform to enable interactive review and improve interpretation of the findings. The platform will include spatial data layers illustrating relative wildfire risk across City open spaces, with particular emphasis on interface areas where development borders natural lands. A composite layer with an associated "priority score" attribute will also be provided to help determine whether existing weed-abatement zones should be expanded. Priority scoring will be informed by a model incorporating structure-exposure risk, burn probability/ wildfire likelihood, and relevant environmental constraints (e.g., slope limitations, sensitive habitats, erosion, etc.). For areas identified as high priority for vegetation management beyond current practices, the composite layer will provide recommendations on treatment frequency, treatment options, cost estimates, and applicable environmental review pathways. Priority areas will be organized into defined "treatment units" to group locations into logical management areas. 2 Vegetation Management Program Effectiveness
Assessment
The purpose of this section is to evaluate the effectiveness of the City's current vegetation management program in meeting regulatory requirements and reducing wildfire risk. The goal is to identify areas where the City's existing vegetation management efforts are effective, where gaps may exist, and where adjustments could further improve wildfire resilience.

2.1 Analysis of Existing Vegetation Management Program
The existing vegetation management program will undergo a comprehensive review to ensure that current practices not only meet regulatory standards but also effectively enhance wildfire protection. This review will encompass an assessment of the program's scope, treatment methods, inspection frequency, maintenance, and geographic coverage. Additionally, the evaluation will analyze the performance of current vegetation treatments in relation to modeled fire behavior, field conditions, and fire history data, aiming to optimize and improve the program's effectiveness.

A gap analysis will be performed to uncover opportunities to enhance the City's existing vegetation management program. This will involve comparing the requirements under applicable codes and standards (OCFA Guidelines and State Fire Code) with current field implementation. GIS layers and program documentation will be overlaid to visualize where treatment areas, widths, and maintenance activities align and/ or diverge from mandated requirements. This analysis will identify areas where vegetation management coverage can be improved, ensure treatments meet or exceed regulatory and industry standards, and pinpoint opportunities to strengthen wildfire protection by addressing gaps in existing City treatment areas.

2.1.1 Verification of Regulatory Compliance
This task will confirm whether the City's vegetation management activities comply with the regulatory vegetation management specifications described in Section 1.1.1 and with applicable OCFA and State Fire Code requirements.

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GIS data, inspection records, and field verification findings will be reviewed to determine whether fuel modification zones, special maintenance areas, and roadside protection zones are maintained in accordance with defensible space widths, vegetation spacing, irrigation standards, and approved plant lists.

The analysis will also compare the City's vegetation management practices to established industry standards from NWCG, CAL FIRE, and OCFA to evaluate conformance with best practices for fuel breaks, defensible space, and ongoing maintenance.

Key areas of focus will include determining where the current program:
• Does not meet OCFA guidelines, such as deficiencies in defensible space width, irrigation, or plant selection.
• Does not meet broader industry standards for fuel break width, spacing, and maintenance. • Is insufficient based on predicted fire behavior modeled in IFTDSS. • Lacks anchoring or continuity, creating areas where wildfire could bypass treatments.

The results of this compliance review will identify areas of deficiency and inform the gap analysis described in Section 2.1.2.

2.1.2 Gap Analysis
A gap analysis will be performed to evaluate how well the City's existing vegetation management program aligns with the regulatory and performance standards outlined in Section 1.1.1 and the modeled fire behavior results presented in Section 1.2. This analysis will overlay the vegetation management treatments currently implemented by the City with the requirements established under OCFA Guideline C-05, the California Fire Code, and the Wildland­ Urban Interface.

GIS layers and program documentation will be compared to identify where treatment areas, widths, and maintenance activities align or diverge from mandated specifications. The analysis will highlight areas where vegetation management coverage is incomplete, where treatment intensity is insufficient to achieve modeled fire risk reduction, or where spatial gaps could allow wildfire to bypass City-managed open spaces. The findings will inform recommendations on program improvements, resource allocation, and coordination with OCFA to enhance the effectiveness of overall vegetation management. The gap analysis will incorporate any identified constraints, such as areas susceptible to erosion or landslide or protected habitat, to identify the areas where these constraints limit treatment options.

2.2 Benefits/Cost Analysis
To evaluate the overall effectiveness and economic value of the City's vegetation management program, a Benefit­ Cost Analysis (BCA) will be performed using FEMA BCA Tool 6.0 and property values from nearby developed parcels.

The analysis will estimate the monetary benefits of wildfire risk reduction achieved through vegetation management activities compared to the costs of implementing and maintaining those treatments.

Benefits will be quantified in terms of avoided property loss, infrastructure damage, emergency response costs, and potential loss of life under both existing and enhanced vegetation management scenarios. Model outputs from the fire behavior simulations, along with the gap analysis in Section 2.1, will provide the data necessary to estimate the potential damage avoided through fuel reduction treatments.

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Costs will include initial implementation, ongoing maintenance, and administration expenses associated with sustaining the vegetation management program. Where the expanded vegetation management program will require additional environmental review to satisfy CEQA reporting requirements, the cost estimate will include the cost to prepare the CEQA document and any supporting technical studies. Where possible, cost data will be drawn from City budget records, contractor invoices, and comparable wildfire mitigation projects in similar jurisdictions.

The resulting benefit- cost ratio (BCR) will serve as a quantitative measure of program efficiency and eligibility for potential funding or grant opportunities under FEMA's Hazard Mitigation Assistance programs. The BCA results will also make recommendations for prioritizing treatment areas that deliver the greatest wildfire risk-reduction benefit per dollar invested.

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3 CEOA Approach Methodology
This section outlines the methodology for determining the most legally compliant and cost-effective approach to environmental review under the California Environmental Quality Act (CEQA) for any proposed expansion or modification of the City's vegetation management program. The intent is to identify the appropriate CEQA pathway, if necessary, and streamline approvals while maintaining the environmental protection standards.

3.1 Determine the Most Cost-Effective CEOA Approach
If expansion or enhancement of the vegetation management program is recommended based on the results of Section 2, the project team will determine the most appropriate and efficient CEQA strategy for implementation.

This analysis will consider the scale and scope of proposed vegetation treatments, their potential to cause environmental impacts, and opportunities to rely on existing documentation or exemptions where appropriate.

3.1.1 Review of Existing Environmental/CEOA Documents and Technical Studies
The first step will be to review existing environmental documentation relevant to the City's open space management and fire prevention efforts. This will include prior Environmental Impact Reports (EIRs), Initial Studies, Mitigated Negative Declarations (MNDs), biological resource assessments, and geotechnical or hydrology studies completed for vegetation management projects in the region. Additionally, Dudek will review previously prepared vegetation management plans to provide recommendations on the appropriate level of CEQA review. The purpose of this review is to do the following:
• Develop an understanding of the level of CEQA analysis, including the required technical studies done on similar vegetation management programs in the region.
• Provide example projects as justification for the recommended level of CEQA Analysis. • Provide the background data to identify constraints (e.g., biological, cultural, geological, etc.) that might impact the level of CEQA analysis required.

The result of this review will be a matrix summarizing the vegetation management projects we reviewed and the level of CEQA analysis performed for each project. The findings from this review and the preparation of the matrix will inform whether a new CEQA document is needed or whether existing analyses can be tiered or supplemented.

3.1.2 Identify Known Environmental Constraints
The next step in the CEQA analysis will be to identify the potential environmental and regulatory constraints that will apply to the open space areas under consideration for inclusion in the vegetation management program.

Constraints may include geologic hazards, protected biological habitats, cultural resources, sensitive species, drainage or erosion-prone areas, and visual resource considerations. Where the location and extent data for these constraints are readily available in a GIS-compatible format, Dudek will add the data layers to the project's wildfire risk assessment and treatment area GIS files. Concurrently with the mapping of constraints, Dudek will revisit the summary of the existing CEQA analysis in Section 3.1.2 to identify how these constraints affected project activities and the steps the project implementers took to avoid or mitigate them. Dudek will prepare a second matrix DUDEK DECEMBER 2025 9

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summarizing the identified constraints, their likelihood of affecting the recommended vegetation management activities, and the available mitigation strategies. Constraints that would not affect the recommended vegetation management activities will not be included in the matrix; instead, a brief justification statement will be provided explaining why the constraint was excluded.

3.1.3 Identification of CEOA Streamlining Options
Vegetation management projects to satisfy defensible space requirements or perform fuel reduction work for fire risk reduction typically do not require CEQA review because the proposed work occurs on disturbed lands and does not propose any activities that will have a significant impact on the environment (e.g., excavation). These activities are generally considered minor land alterations with negligible environmental impact, and their CEQA review can be satisfied with a Notice of Exemption or a similar environmental review document.

Dudek will approach our identification of the appropriate level of CEQA review for the City's vegetation management program, assuming that the vegetation management activities, including our recommended expansions to the program, will meet the criteria for a CEQA exemption.3. This assumption is based on our prior experience with fuel­ reduction projects around structures and supports the most expedient level of CEQA review. Therefore, our identification of the CEQA option will begin with reviewing potential statutory and categorical exemptions, such as those provided under Public Resources Code Section 21080(b)(3) and CEQA Guidelines Section 15304 (Minor Alterations to Land), which often apply to small-scale vegetation thinning, fuel breaks, and defensible space maintenance. Next, Dudek will review the identified constraints and mitigation strategies (including avoidance). If the analysis determines that the recommendations meet the criteria for statutory or categorical exemptions and that the identified constraints can be mitigated without compromising the program's effectiveness, then Dudek will conclude that a Notice of Exemption is the most appropriate CEQA option. This conclusion will include any recommended follow-up studies or surveys, such as nesting bird surveys, to address the identified constraints. If the analysis determines that recommended vegetation management activities exceed the criteria for a statutory or categorical exemption, or that applying the required mitigation measures would compromise the program's effectiveness, Dudek will continue the CEQA analysis to determine the next most efficient level of CEQA review. This analysis will include recommendations for the technical studies to be prepared to support the CEQA environmental document.
3 Fuel reduction activities within 100 to 200 feet of a building generally qualify for a CEQA exemption under Statutory Exemption 152669 (c)
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References
California Building Standards Commission. 2022. California Building Code, Title 24, Part 2, Chapter 7A, "Materials and Construction Methods for Exterior Wildfire Exposure." California Department of Forestry and Fire Protection (CAL FIRE). 2022. California Fire Code, Title 24, Part 9.

Sacramento: California Building Standards Commission.

California Public Resources Code. 2023. § 4291, "Reduction of Fire Hazards Around Buildings." Sacramento:

California Legislature.

City of Laguna Niguel. 2025. City of Laguna Niguel Fire Code, Ordinance No. 2025-238, AN ORDINANCE OF THE CITY OF LAGUNA NIGUEL, CALIFORNIA, ADOPTING BY REFERENCE THE 2025 CALIFORNIA FIRE CODE; TOGETHER WITH CERTAIN AMENDMENTS, DELETIONS, ADDITIONS, AND PENALTIES; AND AMENDING TITLE 11 OF THE

LAGUNA NIGUEL MUNICIPAL CODE
"IFTDSS." Wildland Fire Application Information Portal. Accessed November 13, 2025. https/ / www.wildfire.gov/ application/ iftdss.

National Wildfire Coordinating Group (NWCG). 2023. NWCG Glossary of Wild/and Fire, PMS 205. Boise, ID: National Wildfire Coordinating Group. https:/ /www.nwcg.gov/publications/ pms205.

Orange County Fire Authority. 2021. Fuel Modification Plan Guidelines and Maintenance Program (FMZ, SMA, and RPZ Standards).
"Planning & Development Services." OCFA, October 31, 2025. https/ / ocfa.org/about-us/ departments/ community­ risk-reduction/ planning-development-services/ .

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Appendix D
Figures

City Boundary
City Owned Lands
Cl
SOURCE: City of Laguna Niguel
DU D EK 6 1
i....- = ==-- ~ = ==- Miles
0 0 5
FIGURE 1
City Owned Open Space Areas
City of Laguna Niguel Defensible Space and Vegetation Management Study

City Boundary
Cl
Fire Hazard
Severity Zones
LRA
Moderate
High
- Very High
Non Wild land
SRA
Moderate
~ High
E2ZJ Very High
SOURCE. OSFM, 2025
DU D EI< 6 :J :; 'J I
1o,1 - ~==--- -=== \,l11ec;
FIGURE 2
CAL FIRE Fire Hazard Severity Zones
City of Laguna Niguel Defensible Space and Vegetation Management Study

City Boundary
Ct
City Owned Lands
CJ
Fire Hazard
Severity Zones
LRA
- Very High
SOURCE: OSFM, 2025: City of Laguna Niguel
DUDEK, 1
""- - = =--- -= = ' Miles
:; 5
FIGURE 3
City Very High Fire Hazard Severity Zone
C,ty of I aquna Niguel Defensible Space and Vegetation Management Study

Area 1
Area 2
Area 9
Area 10-- Area 11
FIGURE 4: CITYWIDE WEED ABATEMENT

INDEX MAP
City of Laguna Niguel
N
A 0 0.2 0.4 0.8
~
Miles

CITYWIDE WEED ABATEMENT
AREA 1 - KITE HILL
City of Laguna Niguel
N
A 0 100 200 500 700
P-..-.- Feet

CITYWIDE WEED ABATEMENT
AREA 2 - LA HERMOSA PARK
N
A 0 90 200 400 500
City of Laguna Niguel i---. Feet

CI1YWIDE WEED ABATEMENT
AREA 3 - PIENZA - 50' BAND
N Figure 5iii
A 0 40 80 200 200
City of Laguna Niguel ~
Feet

CITYWIDE WEED ABATEMENT
AREA 4 - DENIA - 30' (S) & 40' WIDE BAND
N Figure 5iv
A 0 40 80 200 200
City of Laguna Niguel
,.._.._ Feet

CITYWIDE WEED ABATEMENT
AREA 5 - GEORGE WHITE ELEMENTARY/ REDONDO VIEW NODE PARK N Figure 5v
A 0 60 100 200 300
City of Laguna Niguel Pi---. Feet

CITYWIDE WEED ABATEMENT
AREA 6 - REEF VIEW NODE - 30' BAND & ALL FLAT AREAS
N Figure 5vi
A 0 40 80 200 200
City of Laguna Niguel Pi-w-. Feet

CITYWIDE WEED ABATEMENT
AREA 7 - PHILLIPS CIRCLE
AREA 8 - RUSSELL LANE
City of Laguna Niguel
N Figure 5vii­
A viii
0 60 100 200 300
~- ~ I ~ Feet

CITYWIDE WEED ABATEMENT
AREA 9 - CATAMARAN WAY - 30' WIDE BAND
N Figure Six
A 0 40 80 200 200
City of Laguna Niguel P-..-.J Feet

CITYWIDE WEED ABATEMENT
AREA 10 - BEAR BRAND PARK
N
A 0 80 200 300 500
City of Laguna Niguel
p-..w.. Feet

CITYWIDE WEED ABATEMENT
AREA 11 - LONGVIEW PARK
City of Laguna Niguel
N
A 0 80 200 300 500
,-_-,_ Feet

City Boundary
Flame Length (ft)
Urban/Non-burnable
- >0-1
>1- 4
>4 - 8
>8 - 11
>11 - 25
- >25
SOURCE
DU D EI< 6 0 0.5 1
•--- = = ..;- - -= = ='Miles

FIGURES
Flame Length ( Peak Summer)
City of Laguna Niguel Defensible Space and Vegetation Management Study

City Boundary
Flame Length (ft)
Urban/Non-burnable
- >0-1
>l - 4
>4 - 8
>8 - 11
>11 - 25
- >25
SOURCE
DU D EI< ! 0 0 5 1
'··- - -= = =-- - -=== ·'Miles
FIGURE 7
Flame Length (Extreme Fall Weather)
City of Laguna Niguel Defensible Space and Vegetation Management Study

City Boundary
D
Burn Probability
Higher
Lower
SOURCE City of Laguna Niguel
DU D EI< & 0 I
- - = =' - - = ~ IV e:;
FIGURE 8
Burn Probability
City of Laguna Niguel Defensible Space and Vegetation Management Study

City Boundary
CJ
Relative Wildfire
Hazard
Lowest
Low
Moderate
1111 High
1111 Highest
SOURCE: City of Laguna Niguel
DU D EI<, u 0.5 1
1,,,- ~ = =--- ~ ==1 Miles
FIGURE 9
Relative Hazard
City of Laguna Niguel Defensible Space and Vegetation Management Study

City Owned Lands
c:::J
Mantained By City Parks
- Required Managment Areas
- SOURCE. City of Laguna Niguel
DU D EI< 6
Figure 10
Weed Abatement Opportunity Area "A" 1BG 3?0
..,__ ..,...-= ...._- - -===· us I e,:1 City of Laguna Niguel Defensible Space and Vegetation Management Study

Appendix E
Graphs

APPENDIX E / GRAPHS
Graph 1. Historical Occurrence of Red Flag Warnings in Los Angeles and Orange Counties \~ NWS [LOX] Los Angeles/Oxnard Red Flag Warning (FW.W) Issued by Year, Month 6 1 2 3 17
2007 2 2 2 2 2 3 24
2008 - 1 2 3 3 12
2009 - 1 2 1 2 2 8
5 2010 - 2 2
2011- 2 3 2 10
2012 1 2 2 2 2 14
2013 - 2 1 9
4 2014 1 1 1 15
._ 2015 - 1 4 Ill
~ 2016 - 2 2 2 16
2017 - 2 2 12
3 2018 - 1 2 1 2 11
2019 -
2020 - 1 12
2021- 2 1 1 1 2 7
2022 - 3 4 r 2
2023 - 1 5
2024 - 2 3 1 2 3 3 15
1 1 6
' ' Total -1
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month (Timezone: America/los_Angeles)
Generated at 27 Mar 2026 3:05 PM CDT in 0.67s
DUDEK E-1
JUNE 2026

APPENDIX E / GRAPHS

INTENTIONALLY LEFT BLANK
DUDEK E-2
JUNE 2026

Appendix F
OCFA C-05 Fuel Modification Guidelines

Orange County Fire Authority
Community Risk Reduction
1 Fire Authority Road, Building A, Irvine, CA 92602 • www.ocfa.org • 714-573-6100 Vegetation Management Guideline:

Technical Design for New Construction
Fuel Modification Plans and
Maintenance Program
Guideline C-05
Serving the Cities of Aliso Viejo • Buena Park • Cypress • Dana Point • Garden Grove • Irvine • Laguna Hills • Laguna Niguel • Laguna Woods • Lake Forest• La Palma • Los Alamitos • Mission Viejo • Rancho Santa Margarita • San Clemente • San Juan Capistrano• Seal Beach • Santa Ana• Stanton• Tustin• Villa Park• Westminster• Yorba Linda• and Unincorporated Areas of Orange County

Fuel Modification Plans Design: C-05 January 1, 2026
Vegetation Management Guideline:

Technical Design for New
Construction Fuel Modification Plans
and Maintenance Program

TABLE OF CONTENTS
INTRODUCTION 3
PURPOSE 3
SCOPE 3
FUEL MODIFICATION PLAN OVERVIEW & SEQUENCING 4
FUEL MODIFICATION ZONES 5

1. Zone A 5

2. Zone B 6

3. Zone C 6

4. Zone D 6
SPECIAL MAINTENANCE AREAS AND ROADSIDE PROTECTION ZONES 7 1 . Special Maintenance Area (SMA) 7

2. Roadside Protection Zones (RPZ) 7
FUEL MODIFICATION PLANS: REQUIRED INFORMATION 8
Section 1: Conceptual Fuel Modification Plans 8
Section 2: Precise Fuel Modification Plans 10
Section 3: Plant Palette Information 11
Section 4: Alternative Materials & Methods Construction Features, & Fire Protection Plans 11

ATTACHMENTS

1. New Construction Inspection Requirements 13

2. Introductory Maintenance Information 15

3. Incline Measurement for Selected Slopes 16

4. Zone Marker Details 17

5. Sample CC&R Maintenance Language 18

6. Requirements for Planting Installation in Fuel Modification Zones 20

7. Undesirable and Invasive Plant Species 22

8. Fuel Modification Zone Plant List 23
2 Fuel Modification Plans Design: C-05 January 1, 2026
Technical Design for New Construction Fuel Modification Plans and Maintenance Program

INTRODUCTION
Vegetation management has proven to be a major factor in reducing the probability of buildings igniting from wildfires. When combined with special building construction features, the potential for ignition is further reduced.

PURPOSE
Fuel Modification Plans help control vegetation design and placement around new structures to limit wildfire impact. These plans ensure that landscaped areas next to buildings are maintained permanently for fire safety.

This guideline provides:
• Design and maintenance requirement for Fuel Modification Zones (FMZ), Special Maintenance Areas (SMA) and Roadside Protection Zones (RPZ) • Standards for both Conceptual and Precise Fuel Modification Plans • Steps to integrate fire-safe landscaping with construction features for long-term protection
Note: For existing structures that were not developed with a fuel modification plan, maintenance shall be completed as required in the Vegetation Management Recommendations/Requirements for Homeowners document found at: OCFA.org SCOPE
All new single-family homes, multi-family residential, Accessory Dwelling Unit (ADU), utility, and commercial structures built in, or adjacent to, a wildfire-risk area or such areas designated by the fire code official, require a Fuel Modification Plan in conjunction with the 2025 California Wildland Urban Interface Code (CWUIC). • Required for State Responsibility Area (SRA) or Local Responsibility Area - Very High Fire Hazard Severity Zone (LRA-VHFHSZ) and High Fire Hazard Severity Zone (LRA-HFHSZ)
• Required per 2025 California Wildland Urban Interface Code, Government Code Section 51175- 51189, and the California Code of Regulations, Title 14 To confirm if your property requires fuel modification, contact the OCFA tech line at (714) 573-6108.

Regulations for wildfire safety are dynamic and new requirements may be enacted by the State of California and its regulatory agencies at any time. Projects must comply with all state requirements for vegetation management and wildfire safety, in addition to the requirements in this guideline, in place at the time of plan submittal. Where a conflict between this guideline and other applicable regulations exists, the more stringent or specific requirement will apply.
3 Fuel Modification Plans Design: C-05 January 1, 2026

FUEL MODIFICATION PLAN OVERVIEW & SEQUENCING
There are two types of fuel modification plans, submitted at different stages of the development process:

1. Conceptual Fuel Modification Plan*
• Submitted before tentative tract map, parcel map, or fire master plan approval • Shows zone layouts, widths, and program intent
• Includes land-use restrictions, tract boundaries, and property lines • Typically reviewed during the Conditional Use Permit (CUP) process and prior to approval of any Tentative Maps
*Note: Conceptual fuel modification plans and precise fuel modification plans can be combined into one submittal when planting plans, final specifications, and inspection information are known.

2. Precise Fuel Modification Plan
• Submitted before grading permit or building permit issuance (whichever comes first) and prior to fire master plan approval
• Includes conceptual fuel modification details and planting plans, final specifications, and inspection information
• May require approval from other permitting agencies (e.g., Coastal Commission, Army Corps, Habitat Management Plan) before OCFA final sign-off

3. Required Inspections (OCFA must be contacted at 714-573-6150 to schedule) • Vegetation Clearance - Before dropping lumber, remove all combustible vegetation within 100 feet of structures, lumber stockpiles, generators, and fuel tanks.
• Final Fuel Modification Inspection - Before occupancy, ensure all zones, irrigation, planting, and access features match approved plans. • Turnover Inspection - When HOA or owner takes over maintenance, meet with OCFA to confirm maintenance responsibility and review requirements. 4 Fuel Modification Plans Design: C-05 January 1, 2026

FUEL MODIFICATION ZONES
The standard FMZ is 170 feet wide, measured horizontally from the structure outward in all directions. It is divided into Zones A (minimum 20 feet), B, C, and D (minimum 50 feet each), with specific design and maintenance requirements for each zone. The width of a more stringent zone may be increased, pushing a less stringent zone farther from the structure or even completely replacing it. For example, an FMZ may be comprised of a 20 foot A zone, a 100 foot B zone, and a 50 foot C or D zone. Some developments may also have Special Maintenance Areas (SMA) or Roadside Protection Zones (RPZ) in addition to the FMZ.

Any project where the entire 170 foot FMZ does not fit on the property, or where any FMZ, SMA, or RPZ does not meet the requirements listed in this guideline, will require an Alternate Materials and Methods (AM&M) request (see Section 4).

Zone A
Width: 20 feet minimum with first 5 feet as the "Immediate Zone" Immediate Zone (0-5 feet):
• No combustible bark or mulch
• Remove all dead and dying plants
• Plants: Irrigated, naturally low growing (2 feet or less), non-woody • Additional Zone A Area Requirements listed below
Zone A Area (0-20 feet):
• Flat level ground (Slopes shall be labeled as B, C or D zone) • No combustible construction allowed
• No grouping of shrubs
• Single specimen shrubs shall be spaced 15 feet apart
• Tree limbs shall be minimum of 10 feet from structures • Irrigated zone (shall have automatic irrigation to maintain high-moisture vegetation) • Plants must be highly fire-resistant, selected from the Fuel Modification Zone Plant List (Attachment 8) or similar species (See Section 3 - Plant Palette Information) • No undesirable and invasive plant species (Attachment 7) 5 Fuel Modification Plans Design: C-05 January 1, 2026
Zone B
Width: 50 feet minimum
•
•
•
•
•
Irrigated zone (shall have automatic irrigation to maintain high-moisture vegetation) Planted with approved species from the Fuel Modification Zone Plant List (Attachment 8) or similar species (See Section 3 - Plant Palette Information) Must comply with planting and maintenance requirements from:
o Attachment 6 - Planting Installation Requirements
No combustible construction is allowed
No undesirable and invasive plant species (Attachment 7) Note: Zone B may be dry if plant selection and design are appropriate ZoneC
Width: 50 feet minimum
•
•
•
•
•
•
Non-irrigated
Shrub and tree coverage up to 50% throughout
Spacing and clearance per Attachment 6 within 100 feet of structures Planted with approved species from the Fuel Modification Zone Plant List (Attachment 8) or similar species (See Section 3 - Plant Palette Information) No combustible construction allowed
No undesirable and invasive plant species (Attachment 7) Zone D
Width: 50 feet minimum
• Non-irrigated
• Shrub and tree coverage up to 70% throughout
• Planted with approved species from the Fuel Modification Zone Plant List (Attachment 8) or similar species (See Section 3 - Plant Palette Information) • No combustible construction allowed
• No undesirable and invasive plant species (Attachment 7) Note: Additional planting restrictions may be required for certain plant species (see Approved Plant Palette Qualification Statements for Select Plant Species on page 31 ).

Note: A clear, brush-free area of 10 feet is required around the perimeter of the ground­ mounted photovoltaic arrays. An approved non-combustible base shall be installed and maintained under arrays and associated electrical equipment installations, 2025 CFC Chapter 1205.5.1.
6 Fuel Modification Plans Design: C-05 January 1, 2026

SPECIAL MAINTENANCE AREAS AND ROADSIDE PROTECTION
ZONES
Interior landscaped areas and roadside plantings inside a community can present a significant hazard during a wildfire. They are subject to planting restrictions, irrigation, and maintenance requirements to protect structures from vegetation fires started by windblown embers and to ensure roadways are available for evacuation and emergency vehicle use during a wildfire.

TYPES OF INTERIOR SLOPES
Special Maintenance Areas (SMA)
• Are areas typically located within a residential community outside of the individual private lots. They are often common areas, and landscaped slopes interior to the residential community perimeter.
• Comply with Zone B requirements
• Start at the property line of privately owned lots
• Minimum of 50 feet irrigated zone
Roadside Protection Zones (RPZ)
• Width: 50 feet from road edge
• Provides a buffer at roadways for safe evacuation and limits fuel load within residential developments and at neighborhood perimeters. • Streetscapes not on the perimeter may not be regulated unless a hazard exists • Comply with Zone B requirements
Maintenance Recording Requirement
Fuel Modification Zones (FMZ), Special Maintenance Areas (SMA), and Roadside Protection Zones (RPZ) must have maintenance responsibilities recorded in CC&Rs or deed restrictions.
• When Zone "A" is on private lots and other zones are HOA/common, a signed homeowner disclosure is required.
• Maintenance must be permanent and consistent with approved plans.

Defensible Space Requirement*
If an SMA or RPZ is within 100 feet of a structure, the first 100 feet is treated as defensible space and must comply with state regulations.
*Note: Alternative designs may be considered through the AM&M process 7 Fuel Modification Plans Design: C-05 January 1, 2026
FUEL MODIFICATION PLANS: REQUIRED INFORMATION
Submittals
• All plans shall be submitted electronically through OCFA's Public Services Portal.

See the OCFA website and Guideline A-02 for more information on plan submittals. • A licensed landscape architect or equivalent qualified design professional should prepare fuel modification plans.

Submittal Sequence
• For an individual residential home lot, the Precise Fuel Modification Plan must be approved prior to approval of the Residential Site Plan. • For commercial or residential developments:
o The Conceptual Fuel Modification Plan must be approved prior to approval of the Tentative Map.
o The Precise Fuel Modification Plan must be approved prior to approval of the Fire Master Plan or, where a Conceptual Fuel Modification Plan is not submitted, prior to approval of the Tentative Map.

Section 1: Conceptual Fuel Modification Plans
Include the following information on your plans, as applicable:

Project Details
□ Show total development size with tract boundary lines, property lines, slope contour lines, and structure foundation footprints.
□ Identify adjoining land uses on all sides (e.g., existing structures, HOA maintained properties, open space, vacant lots, natural vegetation, roads, parks). □ Identify each fuel modification zone within your property (A, B, C & D) as it applies to your project.
□ State whether the project is in an LRA- VHFHSZ, LRA- HFHSZ or SRA. □ Note on plan: "Structures in these zones must meet CWUIC standards." □ Note on plan: "Combustible fencing is prohibited in all Fuel Modification Zones." Topography & Setbacks
□ Show contour lines for slopes and valleys.
□ Identify slopes 20% or greater
Plant Selection
□ All plants must be from the Fuel Modification Zone Plant List (Attachment 8) or follow Section 3 for alternate species.
□ Show the name and location of any retained existing plants (if none, remove all existing vegetation from the plan).
□ Label all interior slopes and common areas as "SMA" or "RPZ". □ If SMA planting plans are not yet designed, note that they require review and approval before installation.
8 Fuel Modification Plans Design: C-05
RPZ Specifications
□ Delineate RPZ areas with either:
• Max 50-foot-wide irrigated Zone "B" (if on community perimeter) • SMA designation (if interior to the community)
January 1, 2026
Legend & Maintenance Notes
□ Clearly symbol and reference each FMZ, SMA, and RPZ in a legend. □ Note each area is irrigated (automatic irrigation) or non-irrigated as required. □ Identify who is responsible for the maintenance of FMZ, SMA, and RPZ.

Access & Covenants
□ Design emergency/maintenance access paths from street frontage to lettered lots:
• At least every 500 feet of FMZ/SMA length
• 7-foot clear width, flat path
□ Record covenants for FMZ/SMA access and maintenance with planning maps and CC&Rs.
□ Note: FMZ, SMA, and RPZ on private lots require recorded easements before plan approval.

Required Plan Inserts
□ Include:
• Attachment 1: New Construction Inspection Requirements • Attachment 2: Introductory Maintenance Information
• Attachment 3: Incline Measurement for Selected Slopes • Attachment 6: Planting Installation Requirements
• Attachment 7: Undesirable/Invasive Plant Species
Special Conditions
□ If Fuel Modification distance requirements cannot be met, follow Alternate Materials & Methods submittal instructions (Section 4).
□ If other agencies restrict vegetation management (e.g., Coastal Commission, Army Corps, Habitat Management Plan), provide their name, maintenance scope, and management plan.

Required Notes to Copy onto Plans (1- 6)

1. The owner/developer will obtain planting plan approval from OCFA before final approval from any other permitting agency.

2. FMZ, SMA, and RPZ areas are purchased/dedicated for wildfire maintenance, beautification, and erosion control.

3. The developer must ensure the HOA dues cover future maintenance costs.

4. If Zone "A" is on homeowner land but other maintenance areas are on HOA/common land, the homeowner must sign a disclosure referencing the lot number in CC&Rs.

5. FMZ, SMA, and RPZ must be maintained in perpetuity for fire safety per CC&Rs, property titles and recorded easements.

6. Prior to dropping lumber, call for a Vegetation Clearance Inspection; combustible vegetation must be removed at least 100 feet from structures and lumber stockpiles. 9 Fuel Modification Plans Design: C-05 January 1, 2026
Additional Requirements
□ Provide CC&Rs confirming maintenance responsibilities before conceptual plan approval.
□ Provide photographs of existing vegetation.
□ Show slope degree/percentage at zone markers to determine actual distance (per Attachment 3).

Section 2: Precise Fuel Modification Plans
Include the following on your Precise Plan:
□ Include Conceptual Plan requirements if no Conceptual Fuel Modification Plan was previously approved, provide additional details from section 1 listed above. □ Show permanent zone marker locations:
• Install the minimum number needed to clearly define side property lines and where Zone D ends
• See Attachment 4 - Zone Marker Details for reference
□ Copy onto the plans:
• Attachment 4 - Zone Marker Details (if applicable)
• Attachment 5 - Sample CC&R Maintenance Language (if applicable) Note: Attachments 4 & 5 are in addition to Attachments required on Conceptual Plan □ Provide written proof that CC&Rs reference fuel modification areas, maintenance responsibilities, and restrictions (see Attachment 5).
□ Provide recorded documentation showing Fuel Modification Zones, SMAs, RPZs, and access/maintenance points are recorded on Tentative Tract Maps. □ Provide note indicating "irrigated" or "non-irrigated" zones □ Submit planting plans for FMZ, SMA, and RPZ (see Section 5). □ Plant Palette Legend: For each plant category, provide the information indicated in the Sample #1: Plant Legend below. See Attachment 8 for plant# and Symbol Code.

Sample #1: Plant Legend -
Plan Botanical Common Plant# from Symbol Code Expected Max Expected Max Plant Form Symbol Name Name Att ach 8 from Attach 8 Growth Height Growt h Width TREES
Plan Botanical Common Plant# from Symbol Code Expected Max Expected Max Plant Form Symbol Name Name Att ach 8 from Attach 8 Growth Height Growth Width SHRUBS
Plan Botanical Common Plant #fr om Symbol Code Expected Max Expected Max Plant Form Symbol Name Name Att ach 8 from Attach 8 Growth Height Growth Width GROUND
COVER
Plan Botanical Common Plant # from Symbol Code Expected Max Expected Max Plant Form Symbol Name Name Attach 8 from Attach 8 Growth Height Growth Width

GRASSES
SPECIES NOT Plan Botanical Common Expected Max Expected Max ON ATTACH 8 Symbol Name Name Growth Height Growth Width 10 Fuel Modification Plans Design: C-05 January 1, 2026 Planting Plans
□ Use Attachment 8 codes and qualification notes before placing plants on plans. □ Space plants per Attachment 6 using max heights and widths from your legend. □ For plants not on the OCFA list, follow Section 3 - Plant Palette Information.

Alternate designs: If required distances, plant species, or irrigation requirements cannot be met, an AM&M request is required. See Section 4.
• Submit technical justification and compensating measures per OCFA Guideline A-

01. • AM&M approval must be obtained before plan approval. □ Required Inspections: Create a heading titled "Required Inspections" on the plan and copy Attachment 1 - New Construction Inspection Requirements under it.

Section 3: Plant Palette Information
Requirements:
• The Fuel Modification Zone Plant List (Attachment 8) was approved by resource agencies responsible for environmental protection. All plants must be selected from Attachment 8 or following the "Proposing Alternate Plant Species" below. • Group and space plants according to Attachment 6 - Planting Installation Requirements.
• Existing plants must be proposed for approval on fuel modification plans. • If planting within 300 feet of reserve lands, written concurrence from the relevant resource agency is required unless prior approval already exists.

Proposing Alternate Plant Species
If proposing species not on the approved list, provide the following information for review:
• Photographs
• Size and growth characteristics
• Species must be equal to or superior to the Attachment 8 approved list in fire­ resistive properties
• Maximum: 10 alternate species per project
Prohibited Plants
• All plants from Attachment 7 - Undesirable and Invasive Plant Species • Plant species with:
o High oil/resin content
o High flammability
o Invasive growth habits
o Excessive litter or deadwood retention
Section 4: Alternative Materials & Methods Construction Features, & Fire Protection Plans
When to Apply for AM&M
• Any FMZ, SMA or RPZ unable to achieve the minimum requirements due to lot size, topography, or existing structures
• Site conditions require modified vegetation management strategies (e.g., cultural, environmental, or historic preservation areas)
11 Fuel Modification Plans Design: C-05 January 1, 2026 Performance Based Design
Projects with insufficient fuel modification zone width(s) may be given consideration for building and site features that reduce the susceptibility of structures to ignition. Such alternative proposals include, but are not limited to:
• Non-combustible walls
• Increased setbacks
• Reduced planting/increased hardscape
• Additional home hardening features exceeding minimum CWUIC requirements Requirements for AM&M proposal

1. Submit an OCFA AM&M request with proposed compensating factors.

2. Follow OCFA Guideline A-01 for AM&M letter format.

3. If approved, copy the AM&M letter directly onto the plans

4. A detailed technical fire behavior analysis by a wildland fire behavior professional may be required on a case-by-case basis.

5. For commercial and multi-lot residential developments, submit a Fire Protection Plan
AM&M Application Checklist
□ Cover letter describing the request and justification □ Fire resistance data or research on proposed plant materials □ Maintenance plan and responsible party identification □ Comparative safety analysis to standard FMZ requirements □ Environmental or site-specific justification (if applicable) □ Fire Behavior Analysis (if applicable)
□ Draft CC&R language for long-term maintenance obligations Fire Protection Plan Requirements:
• Submit with Fuel Modification Plan.
• Fee Code: PR 146 (Fire Protection Plan)
• Does not replace PR 145 (Fire Master Plan).
• Must include special CWUIC screening forms indicating which lots/buildings meet each code section.
• OCFA provides approved plan copies to the Building Department for reference Offsite Landowner Recorded Easements:

A standard fuel modification requires 170 feet of space measured out from the structure.

Where insufficient space is available on the property, it may be possible to arrange an easement with adjacent landowners to extend the fuel modification onto their property. If this approach is used:
• Obtain recorded easements from adjoining landowners.
• Include easement details on plans.

Note: Plans will not be approved without recorded agreements attached (if applicable) 12 Fuel Modification Plans Design: C-05 January 1, 2026 ATTACHMENT 1
New Construction Inspection Requirements
The Builder or Developer shall call OCFA Inspection Scheduling at (714) 573-6150 for the inspections listed below:

Vegetation Clearance Inspection:

Prior to dropping of lumber on the site, all combustible vegetation must be cleared at least 100 feet from:
• Structures under construction
• Lumber stockpiles
• Generators
• Fuel tanks and dispensers
Note: An inspection sign-off or release letter must be issued to the Building Department before construction proceeds.

Final Fuel Modification Inspection:

Prior to occupancy:
• All FMZ, SMA, and RPZ adjacent to structures must:
o Be fully installed
o Have functional irrigation
o Match the approved Fuel Modification Plan specifications • Physical installation includes:
o Zone markers
o Required planting
o Access paths
o Hardscape features
Inspection Notes:
• The developer/builder is responsible for scheduling all inspections. • Any deviation from approved plans must be corrected before final sign-off. • Inspections will not be passed if undesirable/invasive species (Attachment 7) are found present.

Homeowners Association {HOA) or Landowner Maintenance Acceptance from Developer/Bui Ider:

Schedule an Owner Turnover Inspection - This inspection/ meeting must happen with OCFA staff prior to accepting the maintenance responsibility from the developer or builder.
1 . The inspection/meeting must include the following representatives:

1.1. Landscape architect

1.2. Community manager or homeowner

1.3. HOA board member

1.4. Installing landscape company

1.5. HOA landscape company

2. At the time of turnover, the Fuel Modification areas shall be maintained by the developer or builder as originally installed and approved. 13 Fuel Modification Plans Design: C-05 January 1, 2026

3. The accepting landowner is responsible for ensuring the developer or builder sufficiently calculated the amount of revenue needed to perform the on-going maintenance of the FMZs and any SMAs per the approved plans.

4. A copy of the approved plans must be provided to the HOA representatives or homeowner at this time.

5. The Landscape Architect must convey ongoing maintenance requirements to HOA representatives or homeowner and provide OCFA a document stating the fuel modification has been installed per plan.

6. An OCFA written disclosure will be required to be signed by the HOA representatives or homeowner indicating that the HOA or homeowner is aware of the FMZ on their land and that they are aware of the importance of retaining the plans and the ongoing maintenance. The responsibility and necessary language for maintenance must also be stated within the CC&Rs (Refer to Attachment 5: Sample CC&R Maintenance Language).
14 Fuel Modification Plans Design: C-05 January 1, 2026 ATTACHMENT 2
Introductory Maintenance Information
The FMZ, SMA, RPZ shall be maintained in perpetuity for fire safety purposes and shall cause a covenant to be recorded and referenced in the CC&Rs or on the property title when there is no HOA involvement.

Emergency access covenants shall be identified on the tract map indicating the reservation and restriction for permanent entry by the HOA or Fire Authority.

On-going maintenance shall occur to preserve the originally approved design found on the approved Fuel Modification Plans.
a. Spacing shall be maintained in accordance with Attachment 6: Requirements for Planting Installation in Fuel Modification Zones. Plant species and arrangements shown on the plans shall be perpetually preserved. Distances of FMZ, SMA, and RPZ will always remain required and will be specific to the approved Fuel Modification Plan. b. The property owner is responsible for all maintenance of FMZ, SMA, and RPZ. c. Two majntenance actjyjties shall be performed each year, the first during middle- to late-Spring and the second in early- to middle-Fall:
1) Grasses cut to 4 inches after annual seeding
2) Dead and dying, all vegetation litter, and Attachment 7: Undesirable and Invasive Plant Species removed from all zones
3) Maintenance of irrigation systems
4) Replacement of dead or dying vegetation with approved species (proposed changes shall be approved by OCFA)
5) Removal of trees and shrubs not on the approved plans d. If maintained by an HOA, the landscape maintenance company and/or property manager shall inspect the FMZ, SMA & RPZ's throughout the year to identify where specific maintenance activities need to take place.
e. The OCFA may conduct inspections of established fuel modification areas. Ongoing maintenance shall be conducted a minimum of twice each year regardless of the dates of these inspections.
f. The property owner shall retain all approved Fuel Modification Plans. The design and information on the plans shall be used as the basis for maintenance.

Where there is no approved fuel modification plan, ongoing maintenance of vegetation in wildfire risk areas shall be in accordance with the currently posted OCFA Vegetation Management Recommendations/Requirements for Homeowners document at www.ocfa.org. 15 Fuel Modification Plans Design: C-05 January 1, 2026 ATTACHMENT 3
Incline Measurement for Selected Slopes
(See Attachment 4: Zone Marker Details)
Zone widths described in this guideline are measured horizontally. When zones occur on a slope, the distance measured along the ground will be increased- see the diagram below for examples of effective zone widths at various slopes.

Zone Width Slope (Grade)
Slope A B C D 60° (173%)
oo 20' 50' 50' 50'
10° 20' 51' 51' 51'
15° 20' 52' 52' 52'
20° 20' 53' 53' 53'
25° 20' 55' 55' 55'
30° 20' 58' 58' 58'
35° 20' 61' 61' 61'
40° 20' 65' 65' 65'
45° 20' 71' 71' 71' 50° (119%)
50° 20' 78' 78' 78'
60° 20' 100' 100' 100'
45° (100%)
Zone B ZoneC
16 Zone D
40° (84%)
35° (70%)
30° (58%)
25° (47%)
20° (36%)
15° (27%)
10° (18%)

Fuel Modification Plans Design: C-05 January 1, 2026
ATTACHMENT 4
Zone Marker Details
Provide zone markers near the property line at the end of each zone and along each zone boundary within the property where needed to provide a clear line-of-sight delineation of the extent of each zone.

Note: An alternate design may be proposed and approved on a case-by-case basis (e.g., using a large boulder, existing fencing, permanent fixtures, etc.).
1- z
:5 -:­ a. z
w :E 0::: - ::, - I- ;> <( 'q'
:Ei'
~ ~
Co co 0:::
:=c (!) b
0 ~ I
1 - N

1. POST CAP

2. 2"X5" ZONE INDICATOR

3. 1 ½" DIAM ETER GALVANIZED POST

4. CONCRETE FOOTING 2500 PSI@ 28 DAYS

5. FINISH GRADE

6. COM PACTED SUBGRADE
4 17

Fuel Modification Plans Design: C-05 January 1, 2026
ATTACHMENT 5
Sample CC&R Maintenance Language
It is recommended that the following language be included in the CC&Rs recorded for a common interest development:
"The duty of the homeowners' association to perform 'Fire Prevention Maintenance' (as defined below) for all Fuel Modification Zones, Special Maintenance Areas, Roadway Protection Zone, and manufactured interior slopes within the development shall be included as an express obligation in the recorded CC&Rs for the development. Similarly, each Owner whose Lot (or Condominium) is subject to FMZ restrictions (e.g., non­ combustible structure setback, etc.) shall be obligated to comply with such restrictions."

1. The OCFA will be designated as a third-party beneficiary of an HOA's duty to perform "Fire Prevention Maintenance" (as defined below) for all portions of the Association Property or Common Area that constitute FMZs and designated interior/manufactured slopes to be maintained by the H O A , and of any Owner's duty to comply with any FMZ restrictions applicable to their lot or condominium.

Additionally, OCFA shall have the right, but not the obligation, to enforce the HOA's duty to perform such Fire Prevention Maintenance, and to enforce compliance by any owner with any FMZ restrictions applicable to their lot or condominium. In furtherance of such right, the OCFA shall be entitled to recover its costs of suit, including its actual attorneys' fees, if it prevails in an enforcement action against an HOA and/or an individual owner (a sample third-party beneficiary provision to be incorporated into the CC&Rs is attached hereto as Addendum "1 ").

2. As used herein, "Fire Prevention Maintenance" shall mean the following:
a. All portions of the Association Property or Common Area that constitute FMZs or designated interior/manufactured slopes shall be regularly maintained by the HOA on a year-round basis in accordance with the fuel modification plan on file with the property manager for the development. b. The irrigation system for FMZs or designated interior/manufactured slopes shall be kept in good condition and proper working order at all times. The irrigation system shall not be turned off except for necessary repairs and maintenance.
18 Fuel Modification Plans Design: C-05 January 1, 2026 ADDENDUM "1"
Enforcement by the Orange County Fire Authority (OCFA): The OCFA is hereby designated as an intended third-party beneficiary of the Association's duties to perform "Fire Prevention Maintenance" for all portions of the Association Property or Common Areas consisting of FMZs or designated interior/manufactured slopes in accordance with the fuel modification plan, and of each owner's duty to comply with any FMZ or designated interior/manufactured slopes restrictions applicable to their lot or condominium as set forth in the fuel modification plan. In furtherance thereof, the OCFA shall have the right, but not the obligation, to enforce the performance by the association of its duties and any other fire prevention requirements which were imposed by the OCFA or other public agency as a condition of approval for the development (e.g., prohibition of parking in fire lanes, maintenance of the blue reflective markers indicating the location of fire hydrants, etc.). The OCFA shall also have the right, but not the obligation, to enforce compliance by any owner with any FMZ or designated interior/manufactured slopes restrictions applicable to their lot or condominium as set forth in the fuel modification plan. If in its sole discretion, the OCFA shall deem it necessary to take legal action against the association or any owner to enforce such duties or other requirements, and prevails in such action, the OCFA shall be entitled to recover the full costs of said action including its actual attorneys' fees, and to impose a lien against the association property, or an owner's lot or condominium, as the case may be, until said costs are paid in full.
19 Fuel Modification Plans Design: C-05 January 1, 2026 ATTACHMENT 6
Requirements for Planting Installation in Fuel Modification Zones

SHRUB & TREE SPACING
Flat to mild slope: < 20%

SPACING BETWEEN TREES
& TREE GROUPS
JO '111i11. between
each group
group

SPACING BETWEEN

SHRUBS AND TREES

SPACING BETWEEN
SHRUBS or SHRUB
GROUPS
3 x Shrub Height,
15' min.

JO' max.
3 x Shrub Height,
15' min Vertical
Separation
Vegetation
Horizontal Spacing for Slopes less than 20%
Vegetation Less than 2 Feet in Height:
• Classified as ground cover.
• Horizontal spacing and vertical separation not required for ground cover less than 2 feet in height.

Vegetation 2- 6 Feet in Height:
• Classified as shrubs.
• Groups of shrubs are limited to a maximum aggregate diameter of 10 feet. • Groups of shrubs shall be separated from other shrubs or trees by 15 feet or 3x the height of the tallest specimen. The greater distance shall take precedence.
• Groups of shrubs shall be spaced a minimum of 30 feet from structures. • No shrubs allowed within 5 feet of combustible structures. • No shrubs allowed within 15 feet of the edge of a tree canopy.

Vegetation exceeding 6 feet in Height:
• Classified as trees
• 3 trees maximum may be grouped with a minimum 10 foot separation between driplines. • Groups of trees shall be separated from other tree groups by 30 feet measured from the edge of the dripline.

Vertical Separation
• A vertical separation of 6 feet shall be maintained between ground cover and the lowest branches of trees. 20 Fuel Modification Plans Design: C-05

SHRUB & TREE SPACING
Moderate to Steep Slope:
20% or greater
January 1, 2026

SPACING

BETWEEN TREES &

TREE GROUPS
30' min. between
each group**
20 · 111111. between trees
in the same group**
Vertical
Separation
Vegetation
under trees
JO' min

SPACING BETWEEN

SHRUBS AND TREES

SPACING BETWEEN
SHRUBS or SHRUB
GROUPS
4 x Shrub Height*,
15' min.
10' max.
diameter
4 x Shrub Height*,
15' min
** when slope exceeds 40%:
30' min. between all trees
Horizontal Spacing for Slopes 20% and greater
Vegetation Less than 2 Feet in Height:
• Classified as ground cover.
• Horizontal spacing and vertical separation not required for ground cover less than 2 feet in height.

Vegetation 2- 6 Feet in Height:
• Classified as shrubs.
• Groups of shrubs are limited to a maximum aggregate diameter of 10 feet. • Groups of shrubs shall be separated from other shrubs or trees by 4x the height of the tallest specimen.

Note: when slope exceeds 40%, spacing shall be 6x shrub height • Groups of shrubs shall be spaced a minimum of 30 feet from structures. • No shrubs allowed within 5 feet of combustible structures. • No shrubs allowed within 15 feet of the edge of a tree canopy.

Vegetation exceeding 6 feet in Height:
• Classified as trees
• 3 trees maximum may be grouped with a minimum 20 foot separation between driplines. • Groups of trees shall be separated from other tree groups by 30 feet measured from the edge of the dripline.

Note: when slope exceeds 40%, all trees shall be spaced at 30' Vertical Separation
• A vertical separation of 6 feet shall be maintained between ground cover and the lowest branches of trees. 21 Fuel Modification Plans Design: C-05 January 1, 2026 ATTACHMENT 7
Undesirable and Invasive Plant Species
Certain plants are considered to be undesirable and invasive due to their physical or chemical characteristics. Physical properties that would contribute to high flammability include large amounts of dead material retained within the plant, rough or peeling bark, and the production of copious amounts of litter. Chemical properties include the presence of volatile substances such as oils, resins, wax, and pitch. Certain native plants are notorious for containing these volatile substances.

Plants with these characteristics shall not be planted in any fuel modification zones or anywhere within the area covered by Alternate Methods & Materials agreements (see Section 4: Alternate Materials & Methods). Should these species already exist within these areas, they shall be removed because of their invasiveness or potential threat they pose to structures.

PLANT SPECIES {MANDATORY REMOVAL)
Botanical Name Common Name
Adenostoma Fasciculatum Chamise
Adenostoma Sparsifolium Red Shanks
Anthemix Cotula Mayweed
Artemisia Californica California Sagebrush
Brassica Nigra Black Mustard
Brassica Rapa Wild Turnip, Yellow Mustard, Field Mustard Cardaria Draba Hoary Cress, Perennial Peppergrass
Cirsium Vulgare Wild Artichoke
Conyza Canadensis Horseweed
Cynara Cardunculus Artichoke Thistle
Eriogonum Fasciculatum Common Buckwheat
Heterothaca Grandiflora Telegraph Plant
Lactuca Serriola Prickly Lettuce
Nassella/Stipa tenuissima Mexican Feathergrass
Nicotiana Bigelevil Indian Tobacco
Nicotiana Glauca Tree Tobacco
Pennisetum alopecuroides Fountain Grass
Ricinus Communis Castor Bean Plant
Sacsola Austails Russian Thistle/Tumbleweed
Salvia Mellifera Black Sage
Silybum Marianum Milk Thistle
Tamarix Ramosissima Salt Cedar
Urtica Urens Burning Nettle
Ornamental:

Arecaceae *(all palm species) Palms* exception: King Palms Cycas Revoluta Sago Palms
Cortaderia Pampas Grass
Cupressus sp Cypress
Eucalyptus sp Eucalyptus
Juniperus sp Juniper
Pinus sp Pine
22 Fuel Modification Plans Design: C-05 January 1, 2026 ATTACHMENT 8
Fuel Modification Zone Plant List
Symbol Legend
X = Plant species prohibited in wet and dry FMZs adjacent to reserve lands. Acceptable on all other fuel modification locations and zones.

W = Plant species appropriate for use in wet FMZs adjacent to reserve lands. Acceptable in all other wet and irrigated dry (manufactured slopes) fuel modification locations and zones. 0 N
*
= Plant species native to Orange County. Acceptable in all fuel modification wet and dry zones in all locations.
= Plant species acceptable on a limited basis (maximum 30% of the area) in wet FMZs adjacent to reserve lands. Acceptable on all other FMZs. = If locally collected.
** = Not native but can be used in all zones.
n = Plant species acceptable on a limited use basis. Refer to qualification requirements following plant palette.

Yellow row = Plant species susceptible to Invasive Shot Hole Borers {ISHB) infestation.

Code Botanical Name Common Name Plant Form

1. w Abelia x grandiflora Glossy Abelia Shrub
. 2. n Acacia redolens desert carpet Desert Carpet Ground Cover

3. 0 Acer macrophyllum Big Leaf Maple Tree

4. X Achillea millefolium Common Yarrow Low Shrub

5. w Achillea tomentosa Woolly Yarrow Low Shrub

6. X Aeonium decorum Aeonium Ground cover

7. X Aeonium simsii no common name Ground cover

8. w Agave attenuata Century Plant Succulent

9. w Agave shawii Shaw's Century Plant Succulent

10. N Agave victoriae-reginae no common name Ground Cover

11. X Ajuga reptans Carpet Bugle Ground Cover

12. w Alnus cordata Italian Alder Tree

13. 0 Alnus rhombifolia White Alder Tree

14. N Aloe arborescens Tree Aloe Shrub

15. N Aloe aristata no common name Ground Cover

16. N Aloe brevifoli no common name Ground Cover

17. w Aloe Vera Medicinal Aloe Succulent

18. w Alogyne huegeii Blue Hibiscus Shrub

19. 0 Ambrosia chammissonis Beach Bur-Sage Perennial
23 Fuel Modification Plans Design: C-05 January 1, 2026 Code Botanical Name Common Name Plant Form

20. 0 Amorpha fruticosa Western False lndigobush Shrub

21. w Anigozanthus flavidus Kangaroo Paw Perennial/accent 22 0 Antirrhinum nuttalianum ssp. no common name Subshrub

23. X Aptenia cordifolia x 'Red Apple' Red Apple Aptenia Ground cover

24. w Arbutus unedo Strawberry Tree Tree

25. w Arctostaphylos 'Pacific Mist' Pacific Mist Manzanita Ground Cover

26. w Arctostaphylos edmundsii Little Sur Manzanita Ground Cover

27. 0 Arctostaphylos glandulosa ssp. Eastwood Manzanita Shrub

28. w Arctostaphylos hookeri 'Monterey Monterey Carpet Manzanita Low Shrub Carpet'

29. N Arctostaphylos pungens no common name Shrub

30. N Arctostaphylos refugioensis Refugio Manzanita Shrub

31. w Arctostaphylos uva-ursi Bearberry Ground Cover

32. w Arctostaphylos x 'Greensphere' Greensphere Manzanita Shrub

33. N Artemisia caucasica Caucasian Artesmisia Ground Cover

34. X Artemisia pycnocephala Beach Sagewort Perennial

35. X Atriplex canescens Four-Wing Saltbush Shrub

36. X Atriplex lentiformis ssp. breweri Brewer Saltbush Shrub

37. 0 Baccharis emoyi Emory Baccharis Shrub

38. W o Bacharis pilularis ssp. Consanguinea Chaparral Bloom Shrub

39. X Baccharis pilularis var. pilularis Twin Peaks #2 Ground Cover

40. 0 Baccharis salicifolia Mulefat Shrub

41. N Baileya Multiradiata Desert Marigold Ground Cover

42. Nn Bougainvillea spectabilis Bougainvillea Shrub

43. 0 Brickellia californica no common name Subshrub

44. W o Bromus carinatus California Brome Grass

45. 0 Camissonia cheiranthifiloa Beach Evening Primrose Perennial Shrub

46. N Carissa macrocarpa Green Carpet Natal Plum Ground Cover/Shrub

47. X Carpobrotus chilensis Sea Fig Ice Plant Ground Cover

48. w Ceanothus gloriosus 'Point Reyes' Point Reyes Ceanothus Shrub

49. w Ceanothus griseus 'Louis Edmunds' Louis Edmunds Ceanothus Shrub

50. w Ceanothus griseus horizontalis Yankee Point Ground Cover

51. w Ceanothus griseus var. horizontalis Carmel Creeper Ceanothus Shrub

52. w Ceanothus griseus var. horizontalis Yankee Point Ceanothus Shrub

53. 0 Ceanothus megarcarpus Big Pod Ceanothus Shrub

54. w Ceanothus prostratus Squaw Carpet Ceanothus Shrub

55. 0 Ceanothus spinosus Green Bark Ceanothus Shrub

56. w Ceanothus verrucosus Wart-Stem Ceanothus Shrub

57. w Cerastium tomentosum Snow-in-Summer Ground cover/Shrub

58. w Ceratonia siliqua Carob Tree

59. w Cercis occidentalis Western Redbud Shrub/Tree
24 Fuel Modification Plans Design: C-05 January 1, 2026 Code Botanical Name Common Name Plant Form

60. X Chrysanthemum leucanthemum Oxeye Daisy Ground Cover

61. w Cistus Crispus no common name Ground Cover

62. w Cistus hybridus White Rockrose Shrub

63. w Cistus incanus no common name Shrub

64. w Cistus incanus ssp. Corsicus no common name Shrub

65. w Cistus salviifolius Sageleaf Rockrose Shrub

66. w Cistus x purpureus Orchid Rockrose Shrub

67. w Citrus species Citrus Tree

68. 0 Clarkia bottae Showy Fairwell to Spring Annual

69. 0 Cneoridium dumosum Bush rue Shrub

70. 0 Collinsia heterophyllia Chinese Houses Annual

71. W o Comarostaphylis diversifolia Summer Holly Shrub

72. N Convolvulus cneorum Bush Morning Glory Shrub

73. w Coprosma kirkii Creeping Coprosma Ground Cover/Shrub

74. w Coprosma pumila Prostrate Coprosma Low shrub

75. 0 Coreopsis californica Califiornia Coreopsis Annual

76. w Coreopsis lanceolata Coreopsis Ground Cover

77. N Corea pulchella Australian Fuscia Ground Cover

78. w Cotoneaster buxifolius no common name Shrub

79. w Cotoneaster congestus 'Likiang' Likiang Cotoneaster Ground CoverN ine

80. w Cotoneaster aprneyi no common name Shrub

81. X Crassula lactea no common name Ground Cover

82. X Crassula multicava no common name Ground Cover

83. X Crassula ovata Jade Tree Shrub

84. X Crassula tetragona no common name Ground Cover

85. W o Croton californicus California Croton Ground Cover

86. X Delosperma 'alba' White trailing Ice Plant Ground Cover

87. 0 Dendromecon rigida Bush Poppy Shrub

88. 0 Dichelostemma capitatum Blue Dicks Herb

89. N Distinctis buccinatoria Blood-Red Trumpet Vine Vine/Climbing vine

90. N Dodonaea viscosa Hopseed Bush Shrub

91. X Drosanthemum floribundum Rosea Ice Plant Ground Cover

92. X Drosanthemum hispidum no common name Ground Cover

93. X Drosanthemum speciosus Dewflower Ground Cover

94. 0 Dudleya lanceolata Lance-leaved Dudleya Succulent

95. 0 Dudleya pulverulenta Chalk Dudleya Succulent

96. w Elaeagnus pungens Silverberry Shrub

97. 0 Encelia californica California Encelia Small Shrub

98. o* Epilobium canum [Zauschneria Hoary California Fuschia Shrub californica]

99. 0 Eriastrum Sapphirinum Mojave Woolly Star Annual
100. N Eriobotrya japonica Loquat Tree
25 Fuel Modification Plans Design: C-05 January 1, 2026 Code Botanical Name Common Name Plant Form
101. 0 Eriodictycon trichocalyx Verba Santa Shrub
102. W o Eriophyllum confertiflorum no common name Shrub 103. w Erythrina species Coral Tree Tree
104. N Escallonia species Several varieties Shrub
105. W o Eschscholzia californica California Poppy Flower 106. X Eschscholzia mexicana Mexican Poppy Herb
107. N Euonymus fortunei Winter Creeper Euonymus Ground Cover 108. N Feijoa sellowiana Pineapple Guava Shrub/Tree
109. N Fragaria chiloensis Wild Strawberry/Sand Strawberry Ground Cover 110. 0 Frankenia salina Alkali Heath Ground Cover
111. w Fremontondendron californicum California Flannelbush Shrub 112. X Gaillardia x grandiflora Blanketflower Ground Cover 113. w Galvezia speciosa Bush Snapdragon Shrub
114. w Garrya ellipta Silktassel Shrub
115. X Gazania hybrids South African Daisy Ground Cover 116. X Gazania rigens leucolaena Training Gazania Ground Cover 117. 0 Gilia capitata Globe Gilia Perennial
118. w Gilia leptantha Showy Gilia Perennial
119. w Gilia tricolor Bird's Eyes Perennial
120. w Ginkgo biloba Maidenhair Tree Tree
121. 0 Gnaphalium californicum California Everlasting Annual 122. w Grewia occidentalis Starflower Shrub
123. 0 Grindelia stricta Gum Plant Ground Cover
124. Nn Hakea suaveolens Sweet Hakea Shrub
125. w Hardenbergia comptoniana Lilac Vine Shrub
126. N Heliathemum muutabile Sunrose Ground Cover/Shrub 127. 0 Helianthemum scoparium Rush Rose Shrub
128. 0 Heliotropium curassavicum Salt Heliotrope Ground Cover 129. X Helix Canariensis English Ivy Ground Cover
130. w Hesperaloe parviflora Red Yucca Perennial
131. on Heteromeles arbutifolia Tayan Shrub
132. X Hypericum calycimum Aaron's Beard Shrub
133. N lberis sempervirens Edging Candytuft Ground Cover 134. N lberis umbellatum Globe Candytuft Ground Cover
135. 0 lsocoma menziesii Coastal Goldenbush Small Shrub 136. 0 lsomeris arborea Bladderpod Shrub
137. w Iva hayesiana Poverty Weed Ground Cover
138. N Juglans californica California Black Walnut Tree 139. 0 Juncus acutus Spiny Rush Perennial
140. 0 Keckiella antirrhinoides Yellow Bush Penstemon Subshrub 141. 0 Keckiella cordifolia Heart Leaved Penstemon Subshrub 142. 0 Keckiella ternata Blue Stemmed Bush Penstemon Subshrub 26 Fuel Modification Plans Design: C-05 January 1, 2026 Code Botanical Name Common Name Plant Form
143. w Kniphofia uvaria Red Hot Poker Perennial
144. w Lagerstroemia indica Crape Myrtle Tree
145. w Lagunaria patersonii Primrose Tree Tree
146. X Lamprathus aurantiacus Bush Ice Plant Ground Cover 147. X Lampranthus filicaulis Redondo Creeper Ground Cover 148. X Lampranthus spectabilis Trailing Ice Plant Ground Cover 149. w Lantana camara cultivars Yellow Sage Shrub
150. w Lantana montevidensis Trailing Lantana Shrub
151. 0 Lasthenia californica Dwarf Goldfields Annual
152. w Lavandula dentata French Lavender Shrub
152. w Leptospermum laevigatum Australian Tea Tree Shrub 154. w Leucophyllum frutescens Texas Ranger Shrub
155. 0 Leymus condensatus Giant Wild Rye Large Grass
156. N Ligustrum japonicum Texas privet Shrub
157. X Limonium pectinatum no common name Ground Cover
158. X Limonium perezii Sea Lavender Shrub
159. W n Liquidambar styraciflua American Sweet Gum Tree 160. w Liriodendron tulipfera Tulip Tree Tree
161. X Lonicera japonica 'Halliana' Hall's Japanese Honeysuckle Vining Shrub 162. 0 Lonicera subspicata Wild Honeysuckle Vining Shrub 163. X Lotus corniculatus Bird's Foot Trefoil Ground Cover 164. 0 Lotus hermannii Northern Woolly Lotus Perennial
165. 0 Lotus scoparius Deerweed Shrub
166. w Lupinus arizonicus Desert Lupine Annual
167. w Lupinus benthamii Spider Lupine Annual
168. 0 Lupinus bicolor Sky Lupine Flowering annual
169. 0 Lupinus sparsiflorus Loosely Flowered Annual Lupine or Annual Coulter's Lupine 170. w Lyonothamnus floribundus Fernleaf Ironwood Tree ssp. Asplenifolius 171. w Macadamia integrifolia Macadamia Nut Tree
172. w Mahonia aquifolium 'Golden Golden Abundance Oregon Grape Shrub Abundance' 173. w Mahonia nevenii Nevin Mahonia Shrub
174. 0 Malacothamnus fasciculatus Chapparal Mallow Shrub 175. X Malephora luteola Training Ice Plant Ground Cover 176. w Maytenus boaria Mayten Tree Tree
177. w Melaleuca nesophila Pink Melaleuca Shrub
178. N Metrosideros excelsus New Zealand Christmas Tree Tree 179. 0 . Mimulus species Monkeyflower Flower
180. 0 Mirabilis californica Wishbone Bush Perennial
181. N Myoporum debile no common name Shrub
182. w Myoporum insulare Boobyalla Shrub
27 Fuel Modification Plans Design: C-05 January 1, 2026 Code Botanical Name Common Name Plant Form
183. w Myoporum parvilfolium no common name Ground Cover 184. w Myoporum 'Pacificum' no common name Ground Cover 185. 0 Nassella (stipa) lepidra Foothill Needlegrass Ground Cover 186. 0 Nassella (stipa) pulchra Purple Needlegrass Ground Cover 187. 0 Nemophilia menziesii Baby Blue Eyes Annual
188. X Nerium Oleander Oleander Shrub
189. 0 Nolina cismontana Chapparal Nolina Shrub
190. N Nolina species Mexican Grasstree Shrub
191. w Oenothera belandieri Mexican Evening Primrose Ground Cover 192. N Oenothera hookeri California Evening Primrose Flower 193. w Oenothera speciosa Show Evening Primrose Perennial 194. X Ophiopogon japonicus Mondo Grass Ground Cover
195. o* Opuntia littoralis Prickly Pear Cactus
196. o* Opuntia oricola Oracle Cactus Cactus
197. o* Opuntia prolifera Coast Challa Cactus
198. w Osmanthus fragrans Sweet Olive Shrub
199. X Osteospermum fruticosum Training African Daisy Ground Cover 200. X Parkinsonia aculeata Mexican Palo Verde Tree
201. w Pelargonium peltatum Ivy Geranium Ground Cover
202. X Penstemon species Beard Tongue Shrub
203. w Photinia fraseria no common name Shrub
204. w Pistacia chinesis Chinese Pistache Tree
205. X Pittosporum undulatum Victorian Box Tree
206. 0 Plantago erecta California Plantain Annual
207. ** Plantago insularis Woolly Plantain Annual
208. X Plantago sempervirens Evergreen Plantain Ground Cover 209. w Plantanus racemosa California Sycamore Tree
210. w Plumbago auritulata Plumbago Cape Shrub
211. 0 Popolus fremontii Western Cottonwood Tree
212. X Portulacaria afra Elephant's Food Shrub
213. 0 Potentilla glandulosa Sticky Cinquefoil Subshrub 214. X Potentilla tabernaemontanii Spring Cinquefoil Ground Cover 215. X Prunus caroliniana Carolina Cherry Laurel Shrub/Tree 216. 0 Prunus ilicifolia ssp. llicifolia Holly Leafed Cherry Shrub 217. X Prunus lyonii Catalina Cherry Shrub/Tree
218. N Punica granatum Pomegranate Shrub/Tree
219. w Puya species Puya Succulent/Shrub
220. w Pyracantha species Firethorn Shrub
221. 0 Quercus agrifolia Coast Live Oak Tree
222. o n * Quercus berberdifolia California Scrub Oak Shrub 223. o n * Quercus dumosa Coastal Scrub Oak Shrub
224. X Quercus engelmannii Engelmann Oak Tree
28 Fuel Modification Plans Design: C-05 January 1, 2026 Code Botanical Name Common Name Plant Form
225. X Quercus suber Cork Oak Tree
226. X Rhamnus alaternus Italian Buckthorn Shrub
227. 0 Rhamnus californica California Coffee Berry Shrub 228. 0 Rhamnus crocea Redberry Shrub
229. 0 Rhamnus crocea ssp. llicifolia Hollyleaf Redberry Shrub 230. N Rhaphiolepis species Indian Hawthorne Shrub
231. 0 Rhus integrifolia Lemonade Berry Shrub
232. N Searsia Lancea African Sumac Tree
233. o n Rhus ovata Sugar bush Shrub
234. 0 Ribes aureum Golden Currant Shrub
235. 0 Ribes indecorum White Flowering Currant Shrub
236. 0 Ribes speciosum Fuschia Flowering Gooseberry Shrub 237. w Ribes viburnifolium Evergreen currant Shrub
238. o* Romneya coulteri Matilija Poppy Shrub
239. X Romneya coulteri 'White Cloud' White Cloud Matilija Poppy Shrub 240. W n Rosmarinus officinalis Rosemary Shrub
241. W n Salvia greggii Autums Sage Shrub
242. W n Salvia sonomensis Creeping Sage Ground Cover
243. 0 Sambucus mexicana Mexican Elderberry Tree
244. w Santolina chamaecyparissus Lavender Cotton Ground Cover 245. w Santolina virens Green Lavender Cotton Shrub
246. 0 Satureja chandleri San Miguel Savory Perennial
247. 0 Scirpis scutus Hard Stem Bulrush Perennial
248. 0 Scirpus californicus California Bulrush Perennial 249. X Sedum acre Goldmoss Sedum Ground Cover
250. X Sedum album Green Stonecrop Ground Cover
251. X Sedum confusum no common name Ground Cover
252. X Sedum lineare no common name Ground Cover
253. X Sedum x rubrotinctum Pork and Beans Ground Cover 254. X Senecio serpens no common name Ground Cover
255. 0 Sisyrinchium bellum Blue Eyed Grass Ground Cover 256. 0 Solanum douglasii Douglas Nightshade Shrub
257. 0 Solanum xantii Purple Nightshade Perennial
258. w Stenicarpus sinuatus Firewheel Tree Tree
259. w Strelitzia nicolai Giant Bird of Paradise Perennial 260. w Strelitzia reginae Bird of Paradise Perennial
261. 0 Symphoricarpos mollis Creeping Snowberry Shrub
262. w Tecoma stans (Stenolobium stans) Yellow Bells Shrub/Small Tree 263. X Tecomaria capensis Cape Honeysuckle Ground Cover 264. N Teucarium chamedrys Germander Ground Cover
265. N Thymus serpyllum Lemon Thyme Ground Cover
266. N Trachelospermum jasminoides Star Jasmine Shrub
29 Fuel Modification Plans Design: C-05 January 1, 2026 Code Botanical Name Common Name Plant Form
267. 0 Trichosstems lanatum Woolly Blue Curls Shrub
268. X Trifolium hirtum 'Hyron' Hyron Rose Clover Ground Cover 269. X Trifolium fragerum 'O'Connor's' O'Connor's Legume Ground Cover 270. 0 Umbellularia californica California Laurel Tree
271. 0 Verbena lasiostachys Western Vervain Perennial
272. N Verbena peruviana no common name Ground Cover
273. X Verbena species Verbena Ground Cover
274. X Vinca minor Dwarf Periwinkle Ground Cover
275. 0 Vitis girdiana Desert Wild Grape Vine
276. X Vulpia myuros 'Zorro' Zorro Annual Fescue Grass
277. w Westringia fruticosa no common name Shrub
278. w Xannithorrhoea species Grass Tree Perennial, Accent shrub 279. w Xylosma congestum Shiny Xylosma Shrub
280. X Yucca Species Yucca Shrub
281. 0 Yucca whipplei Yucca Shrub
30 Fuel Modification Plans Design: C-05 January 1, 2026 Approved Plant Palette Qualification Statements for Select Plant Species

2. Acacia redolens desert carpet: May be used in the furthest ½ of the "B" FMZ from the structure, and no closer than 25 feet from the edge of the zone nearest the structure. The plants may be planted with a minimum spacing at 10 feet on center, maximum spacing in meandering zones not to exceed a mature width of 24 feet and mature height of 24 inches.

If acacia redolens desert carpet is used in the roadway protection zone, it shall be maintained at a minimum of 25 feet from the curb face. At the time of precise plan review, the mature spacing shall be accounted for.

42. Bougainvillea spectabilis (procumbent varieties): Procumbent to mounding varieties may be used in the mid "B'' FMZ. The plants may be planted in groups at 6 feet on center spacing not to exceed eight plants per group. Mature spacing between individual plants or groups shall be at a 30 foot minimum.
125. Hakea suaveolens: May be used in the mid "B" FMZ. The plants shall be used as single specimens with mature spacing between plants of 30 feet minimum. 132. Heteromeles arbutifolia: May be used in the mid to lower "B" FMZ. The plants may be planted in groups of up to 3 plants per group. Mature spacing between individual plants or groups shall be at a 30 foot minimum.
160. Liquidambar styraciflua: May be used in the mid "B" FMZ. The plant shall be used as single specimens with mature spacing between trees and a 30 foot minimum. 223. Quercus berberdifolia: Additional information may be required as directed by the OCFA unless approved on the plan as shown.
224. Quercus dumosa: May be used in the mid to lower "B" FMZ. The plants may be planted in groups of up to 3 plants per group. Mature spacing between individual plants or groups shall be at a 30 foot minimum.
234. Rhus ovata & Rhus integrifolia: May be used in the mid to lower "B" FMZ of inland areas only. The plants may be planted in groups of up to 3 plants per group. Mature spacing between individual plants or groups shall be at a 30 foot minimum. 241. Rosmarinus officinalis: When used as a ground cover, it shall be maintained at 2 feet in height. Additional information may be required as directed by the OCFA. 242. Salvia greggii: Additional information may be required as directed by the OCFA unless approved on the plan as shown.
243. Salvia sonomensis: May be used in the mid to upper "B" FMZ. The plants may be planted in groups of up to 3 plants per group. Mature spacing between individual plants or groups shall be at a 15 foot minimum.
31 Appendix G
Additional Tables

APPENDIX G / ADDITIO NA L TABLES
Elevation USGS 10-m Elevation
Slope USGS 10 -m Slope
Aspect USGS 10-m Aspect
Fuel Model Composite of NCC Orange County Vegetation Classifications and LANDFIRE 2024 - resampled to 10-m
Canopy Cover National Land Cover Database (NLCD) Tree Canopy Cover (2023) Canopy Height LANDFIRE 2024 - resampled to 10-m
Canopy Base Height LANDFIRE 2024 - resampled to 10-m
Table G-2. Wildfire Behavior Modelin
Wind Speed* 20 mph 30 mph
Wind Direction 271 degrees West 58 degrees Northeast
Wind Type Gridded Gridded
1-Hour Fuel Moisture 6% 2%
10-Hour Fuel Moisture 9% 3%
100-Hour Fuel Moisture 13% 5%
Herbaceous Fuel Moisture 60% 30%
Live Woody Fuel Moisture 90% 60%
Crown Fire Calculation Method Scott/ Reinhardt Scott/ Reinhardt Note:
* 20- foot wind speed, which is converted to midflame windspeed, using Wind Adjustment Factor (WAF) 1) Kite Hill No Anchor points The north end connects to the fuel break on the adjacent property
2) La Hermosa Park N. and S. La Hermosa Park The entire open space area is maintained.
3) Pienza 50 ft Band No Anchor points
4) Denia 30 & 40 ft Band No Anchor points
5) George White Elementary/
Redondo View Node Park
N. Chapparosa Park Rd. S. Service
Road
6) Reef View Node E. Service Road, W. Service Road The treatment area is not near structures.
7) Phillips Circle E. Unnamed Park. W. Unnamed
Park
8) Russell Lane E. Ridgeway Ave., W. Unnamed
Park
9) Catamaran Way 30 ft Band No Anchor points
10) Bear Brand Park No Anchor points
11) Longview Park N. Longview Park, S. No Anchor
point
- - - - - - - - - - - - = Weed Abatement Area is within the VHFHSZ DUDEK G-1
JUNE 2026

APPENDIX G / ADDITIO NAL TABLES
Table G-4. List of Weed Abatement Areas and Adjacent HOAs Weed Abatement Area HOA Comments
1) Kite Hill No HOA (County-Owned) Orange County Harbors Beaches and Park District and Niguel
Botanical Preserve border area.
2) La Hermosa Park No HOA (City Property) N/A
3) Pienza Marina Hills Planned Community Work with the HOA to connect • 50 ft Band Assoc. vegetation management areas to
good anchor points.
4) Denia Marina Hills Planned Community Work with the HOA to connect • 30 & 40 ft Band Assoc. vegetation management areas to good anchor points.
5) George White Elementary/ Laguna Heights Community Assoc., N/A Redondo View Node Park Laguna Heights Homeowner Assoc.
6) Reef View Node Laguna Heights Community Assoc N/A
7) Phillips Circle Beacon Hill Planned Community N/A
Assoc.
8) Russell Lane Bear Brand at Laguna Niguel N/A
9) Catamaran Way Quissett Bay Work with the HOA to connect • 30 ft Band vegetation management areas to
good anchor points.
10) Bear Brand Park San Marin, Beacon Hill Planned Work with the HOA to connect Community Assoc. vegetation management areas to
good anchor points.
11) Longview Park Bear Brand at Laguna Niguel N/A
I • = Weed Abatement Area is within the VHFHSZ
DUDEK G-2
JUNE 2026