Defensible Space Inspection Program
The Defensible Space Program is a joint effort between the County of Los Angeles Fire Department and the County of Los Angeles Agricultural Commissioner Weights and Measures Department, Weed Hazard and Integrated Pest Management Bureau. This unified enforcement legally declares both improved and unimproved properties a public nuisance, and where necessary, requires the clearance of hazardous vegetation.
These measures create “Defensible Space” for effective fire protection of lives, the environment, and property. The Department’s Defensible Space Unit enforces the Fire Code as it relates to brush clearance on improved parcels, coordinates inspections and compliance efforts with fire station personnel, and provides annual defensible space training to fire station personnel.
Our objective is to create the Defensible Space necessary for effective fire protection in newly constructed and/or remodeled homes within the Department’s Very High Fire Hazard Severity Zones (VHFHSZ). Fuel modification reduces the radiant and convective heat, and provides valuable defensible space for firefighters to make an effective stand against an approaching fire front. Fuel modification zones are strategically placed as a buffer to open space, or areas of natural vegetation and generally would occur surrounding the perimeter of a subdivision, commercial development, or isolated development of a single-family dwelling.
Fire Hazard Severity Zones (FHSZ)
While all of California is subject to some degree of fire hazard, there are specific features that make some areas more hazardous. The California Department of Forestry and Fire Protection (CAL FIRE) is required by law to map areas of significant fire hazards based on fuels, terrain, weather, and other relevant factors. These zones, referred to as Fire Hazard Severity Zones (FHSZ), influence how people construct buildings and protect property to reduce risk associated with wildland fires. The maps were last updated in the mid-1980s and early 1990s.
To see if a parcel is within the FHSZ, please visit the LACounty GIS Viewer
- Go to “Map Layers” on the left side of the screen and click on the down arrow for “Map Theme”
- Look and select “Hazards”
- Click on the plus symbol (+) and expand the “Hazards” menu
- Look for “Fire Hazards” and click on the Plus symbol (+) and expand the “Fire Hazards” menu
- Select “Fire Hazard Severity Zones” and the FHSZs will appear on the map
- If you would like to see the FRA, SRA and LRA, select “Fire Hazard Responsibility Areas”
VEGETATION MANAGEMENT PROGRAM
As the population of the County of Los Angeles increases, further expansion of residential areas into the wildland urban interface is inevitable. Panoramic views, wildlife, fresh air, and solitude are just a few of the reasons that tempt people to locate to brush areas in the County of Los Angeles. The rewards may be numerous, but the increased risk of wildfires, flooding, and erosion pose a serious threat to life, property, and the environment.
The County of Los Angeles Fire Department created the Vegetation Management Program in 1979 to develop strategies for responding to the growing fire hazard problem. These include:
- An ongoing effort to analyze the history and effects of wildland fires in Los Angeles County.
- Development of fuel management projects with stakeholders, including cities, community groups, and other agencies; experimentation with various methods of reducing or removing fuels in fire prone areas, as well as evaluation of environmental impacts and effects of these practices. Thousands of homes have been lost in wildland fires. Many of these were lost due to unmanaged vegetation around them. Wildland fire behavior is strongly influenced by vegetation (fuel) type, fuel moisture, the arrangement and continuity of fuels, slope, aspect, and weather.
- Vegetation can be modified and managed, but as long as people choose to live in wildland areas, the threat of major catastrophe exists. Vegetation management, related to wildland fire, refers to the total or partial removal of high fire hazard grasses, shrubs, or trees. In addition to fire hazard reduction, vegetation management has other benefits, including: increased water yields, improved habitat for wildlife, reduction of invasive exotic plant species, and open access for recreational purposes.
Los Angeles County encompasses a land area of 4,000 square miles. 47% of this area is mountainous, while the remainder consists of alluvial valleys, coastal plains, and high desert. Mountain ranges within the County run from east to west. Primary canyon drainages flow north and south. This natural topography creates airflow patterns linking the desert with the Pacific Ocean. During periods of high meteorological pressure zones over the desert, hot, dry, northerly winds known as Santa Anas follow these paths. The high frequency of fires in north/south drainages has earned them the name fire corridors. Prominent fire corridors in Los Angeles County include Malibu, Arroyo Seco, and San Gabriel Canyons.
Chaparral is the vegetative ecosystem present on most watersheds in Los Angeles County. The term applies to the shrubby vegetation seen on both coastal and inland hillsides. Chaparral can be separated into two types; soft chaparral (usually called coastal sage scrub) and the taller hard chaparral. It is dominated by evergreen and drought deciduous shrubs 1 to 15 feet tall. Most of these plants are recognized by tough, leathery leaves that reduce water loss in dry conditions. Many chaparral plants contain volatile oils which produce a strong odor and increase flammability.
Common examples include various species of Ceanothus, Manzanita, Sage, Sumac, Toyon, and Chamise. Chaparral ecosystems are very efficient at controlling erosion and protecting watersheds. Deep root systems stabilize slopes and allow plants to thrive in the dry Southern California Mediterranean climate. Chaparral plant communities depend on fire as an integral part of their life cycle, and periodic burning is essential for these communities to rejuvenate. As unburned plants grow older, the amount of dead material increases dramatically. By age 50 as much as 50% of an individual plant may be dead. Where chaparral plants cover a broad area and are uniformly old and senescent, fires tend to be large and devastating.
There are 5 methods currently being used by the County of Los Angeles Fire Department to manage over-aged chaparral stands:
Prescribed Fire
The confined application of fire to a preselected area of land in order to minimize the amount of fuel in the area. Prescribed fires are carried out only under specific weather and fuel conditions, and is used to mimic nature’s own process of regeneration.
Biological Control
The reduction of plant volume using grazing or browsing animals, such as goats, to hold growth back and maintain low fuel volume.
Mechanical Brush Removal
The use of mechanical equipment to reduce vegetation in an area. Equipment consists mainly of a bulldozer, in combination with a “brush crusher”, a brushrake, disk or anchor chain, which crushes or removes the vegetation.
Hand Clearing
The use of manual labor to remove brush with an assortment of tools including the Pulaski, hand axe, Grubbing hoe, chain saw, handsaw and others to modify vegetation arrangement. This is the most common method used by property owners to meet Fire Code requirements.
Chemical Application
The application of growth inhibitors, defoliators or killers to reduce highly flammable herbaceous or poisonous plants such as annual grasses or poison oak.
Data gathering techniques provide vegetation managers with information necessary to carry out their programs. This data can help identify project areas and predict the chaparral conditions, as well as anticipate fire behavior.
Fuel Sampling
Live fuel moisture plant samples are taken at regular intervals and weighed, then dried and weighed again, to determine the moisture content in Chaparral. It is a major determinant in how the brush will burn. These measurements, when used in conjunction with other data, can be used to assess fire hazards and predict fire behavior for use in fire control, fire prevention, and prescribed fire activities.
Weather Monitoring
Appropriate and predictable weather conditions are critical for prescribed burns. Temperature, humidity, and wind is constantly monitored in order to maintain safe operations.
Fire Planning – Geographic Information Systems
The County of Los Angeles Fire Plan Unit is responsible for implementing the California Fire Plan, a statewide framework for minimizing costs and losses from wildland fires. The Fire Plan Unit utilizes a Geographic Information System (GIS) to identify high hazard\high value areas and communities at risk in the wildland-urban interface.
Identification of fire hazard\risk areas is achieved by assessing and validating fire environment components (Fuels, Weather, Topography, and Assets at Risk) in Los Angeles County. Areas identified through the Fire Plan process as Communities at Risk (CAR) and\or “Very High Fire Hazard Severity Zones” (VHFHSZ), are targeted for focused Pre-Fire Management projects by the Department’s Vegetation Management Program.
Smoke Management
The release and tracking of weather balloons measuring wind speed and direction allows managers to predict where smoke from a prescribed fire or chemicals will drift. Treatment methods can then be carried out under conditions to keep smoke and related chemicals away from structures, roads, and developed areas. Differences in wind patterns at ground level and aloft can help predict possible changes in fire behavior.
Aerial Imagery
The use of aerial photographs and infrared imagery enables managers to recognize areas of high priority for vegetative fuel.
Natural Occurrences Affecting Chaparral
The health of chaparral communities can vary. Drought, frost and abnormally high rainfall can cause vegetation die back. Other possible dieback causes range from fungus infections to air pollution side effects. Post Burn evaluations of pre- and post-fire treatments are conducted to create and utilize best management practices for vegetation management. Vegetation condition, erosion, effects on wildlife and adverse environmental factors are a few of the subjects being studied. Close monitoring and record keeping of effects allows Fire Department managers to continually improve vegetation management techniques.
Agreements with Other Agencies Bill 1704
State of California Senate Bill No. 1704 sets forth guidelines for prescribed burning in California. This Bill grants the Los Angeles County Fire Department the authority to burn brush covered lands in order to reduce hazardous wildfire conditions. A private landowner may have up to 90% of the costs incurred for prescribed burning covered by the Vegetation Management Program if their primary objectives include the following: conversion of brush-covered areas into grazing land, fire prevention and structure protection, watershed protection and conservation, or range and forage improvement. If all of the terms of the burning permit are followed and the fire escapes, fire suppression costs will be covered under a third-party liability policy of insurance.
Coordinated Resource Management Agreement
This agreement allows the Fire Department to act as the lead in cooperation with other governmental agencies in projects concerning natural resources. On prescribed burns where several agencies share an interest, coordination plays an especially important role.
- Cost effective
- Ecologically sound: fire is a natural part of the chaparral ecosystem.
- Can be carried out day or night.
- Increases forage and browse.
- Eliminates need for debris removal.
- Temporary reduction in the scenic quality.
- May cause changes in the physical characteristics of the soil.
- Temporary smoke emissions.
- More cost effective than hand clearing.
- Fast progress.
- Requires that debris be chipped or burned.
- Causes soil disturbance, increased sedimentation, erosion.
- May leave physical scars on the land.
- Unsuitable for critical hazard slope gradients.
- Cannot be used on rocky ground.
- Debris removal is more difficult when mixed with soil.
- Can be used selectively to treat small areas.
- Can be applied on rough and rocky terrain.
- Used to prepare vegetation for burning and maintaining low-density brush stands.
- Can be inexpensive to apply.
- Legal and/or political restrictions.
- Can cause offsite damage due to drift.
- Requires close supervision.
- Effects may be short-lived.
- Not useful for the initial clearance of native vegetation.
- Requires removal of debris.
- Can be weather dependent.
- Not feasible for large areas
- Goats are efficient converters of woody plants.
- Goats will readily eat regrowth up to 5 years old.
- Eliminates need for debris removal.
- Can be done on rocky, steep, slopes.
- Sheep and cattle do not efficient convert woody plants.
- Cost is difficult to establish and depends upon availability of animals, cooperation, and product marketability.
- Requires fencing or herding to properly control the amount of vegetation removed.
- Minimum disturbance of site.
- Desirable for clearing around or through special interest areas such as archaeological or historical sites, areas containing distinctive plants, or where visual effects are critical.
- Appropriate for thinning or species selection.
- Preserves riparian zones.
- Expensive.
- Slow.
- High manpower requirements.
- Requires consistent follow up after initial clearing to get brush under control.
- Requires that debris are chipped, burned and removed.
