LANDSCAPE (DESIGN)
A resilient landscape is fire-wise, water wise and promotes biodiversity by using California native plants. These gardens use sustainable practices, plant selection, and maintenance to reduce the risk of fire in the defensible space zone. Resilient gardens save water, protect us from fire and promote biodiversity.
Zone 0: 0-5′ from structures
The Ember-Resistant Zone (ERZ)
The Ember-Resistant Zone is the first 5 feet around your home, including the structure itself. The objective in this zone is to avoid ignitions from windblown embers landing on or near the direct surroundings of the house and starting a fire. Ember ignitions are responsible for the majority of homes lost or damaged in wildfires. In the Ember-Resistant Zone, all home building materials, vegetation, equipment, outdoor furniture, toys or anything else that could be ignited by embers must be removed or replaced. Research from the Insurance Institute for Business and Home Safety (IBHS) shows that appropriately managing the first 0 to 5 feet around the house has the greatest impact on reducing the risk of losing a home to wildfire.
No vegetation is recommended within 5 feet of any structure. No organic landscape mulch or wood chips should be utilized. Incorporate pathways of gravel, pavers, or concrete. Existing trees may overhang the roof, but maintain a distance of 5 feet (10 feet from chimneys), and clean roof and gutters regularly.
Zone 0: 0-5′ from structures
Defensible space is an area around a home or other structure that is designed, modified, and/or maintained in a way that increases the probability of the home surviving a wildfire event. All vegetation, whether native or non-native, are potential fire fuel. Through proper planning, you can have both a beautiful native landscape and a fire-wise home. Fire-wise landscapes should also include hardscape elements, such as granite paths, patios, and stone walls. These can act as fuel breaks in-between islands of native vegetation to help slow down or change the path of an approaching fire.
The size of the zones shown above are supported by research into home losses in wildfires, and are consistent with most local regulations at the time of publication. Based on this evidence and current CalFire standards, we show a maximum distance for vegetation modification of 100′ from the house. However, the type of vegetation, terrain, and local regulations may require additional thinning beyond 100′. Contact your local Fire Department for specific requirements.
Native vegetation is often protected by regulations, so do not remove previously unmodified habitat without first contacting your local County planning department for specific limitations and processes.
Recommendations for Zone 0: 0-5′ from structures
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No vegetation is recommended within 5 feet of any structure. |
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Keep the area surrounding your structures clear of combustible materials such as furniture and accessories, natural fiber doormats, garbage and recycling containers, lumber, firewood, and clutter.
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Install hard surfaces, such as concrete walkways, or use noncombustible mulch products such as rocks and gravels. Photo by Ellie Insley. |
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Clean up all fallen leaves and needles, and keep any remaining plants free of dead material. | |
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Wood fences and hedges should not extend into Zone 0 or connect to the house. | |
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Include footprint of any attached structure, such as a deck, within the Ember-Resistant Zone, and do not store firewood, lumber or combustibles here. Consider installing screening that is 1/8” mesh or smaller to keep debris and embers from entering areas under decks.
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Plant Selection
Optimally, no vegetation is recommended within 5’ of any structure. Particularly important is to avoid plants in front of or below windows, in corners and under eaves. The highest standard is to have no combustible materials in zone 0, however irrigated non-woody herbaceous plants may be considered if less than 16” in height and set back from structures and decks. Plants should have high water content. Any vegetation that remains in this zone should be pruned to reduce the amount of fire fuel. Thinning the plant from the inside is recommended. Hedging the tops and sides of plants causes fine twiggy growth and a build up of plant debris, increasing ignitability.
Trees
- Do not plant trees in the Ember-Resistant Zone.
- Remove tree limbs that extend into this zone. Tree branches can overhang the roof if 5’ clearance is maintained (10’ from chimneys), but removal of leaves and debris from the roof and gutters is critical!
Potted Plants
The ember-resistant zone is a no planting zone. Although not directly planted, any potted plants should be well-maintained and follow these guidelines. As a general rule, we recommend keeping potted plants outside that zone at all times since heavy pots can be hard to move. If you keep potted plants in this zone, they should be non-combustible pots (such as ceramic, metal or cement) with a maximum vegetation height of two feet.
- Do not plant invasive species. They can generate seeds and contaminate the natural environment. Click here for INVASIVE section.
- Make sure your potted plants are well maintained and watered.
- Remove any debris and dead material from your potted plant. Any leaf litter within the pot can be ignited by embers.
Typical Amenities in Zone 0
- Make sure the amenities are movable, not in contact with your structure (ideally outside the 5-foot zone) and with a minimum of 12 inches vertical space from any window.
- For non-movable amenities (e.g. rain barrels) make sure they are made of non combustible material (e.g. metal).
- Any movable amenities should be placed outside the Ember-Resistant Zone during Red Flag Warnings. Click here for CAL FIRE Red Flag warnings page.
Typical Accessories in Zone 0
If you have combustible accessories such as awnings, shades / cabanas, play-sets, or decks, make sure to extend your Ember Resistant Zone and include 5 feet of non-combustible area around these structures.
About Leaf Blowers
In early summer, give your leaf blower a vacation; use a rake instead. Leaf blowers blow away mulch and topsoil, and they contribute to air and noise pollution. They are also a fire hazard due to engine heat and the sparks they can generate. Check local regulations, as some cities no longer allow the use of gas leaf blowers.
Work with Your Neighbors
- In most cases, the most effective solution is a cooperative approach between neighbors. Many homes do not have 100’ of space between structures and parcel lines. Property owners are required to maintain defensible space to their property line. Help your neighbors create defensible space for their homes, and ask neighbors for help if their property threatens yours.
- Remember that the most important zone is closest to your structures – from zero to five feet. If you’ve taken all the steps outlined here and worked to “harden” your home, neighboring properties typically present only a minimal risk.
Zone 1: 5-30′ from structures
The Home Protection Zone
The Home Protection Zone should be designed to create and maintain a landscape that, if ignited, will not transmit fire to the home. Depending upon the type of wildland vegetation in the area and the steepness of the slope, this zone should extend at least 30 feet from the home, (or more for slopes above 20%). Occasional trees and taller shrubs are possible in this zone, but planning should avoid future ladder fuels.
The Home Protection Zone should be designed to promote fire-wise landscaping and water conservation. Use mostly plants that are 3’ tall or less at maturity. The goal is to create a low-ignition landscape capable of slowing down fire spread. Plants that are green and lush give better protection. If appropriately watered and pruned to remove dead or unhealthy material, these plants will be far less likely to carry fire to your home. While all plants will eventually burn, healthy ones with adequate moisture content are more difficult to ignite.
As you rethink your home landscape for greater fire resilience, we encourage you to consider native plants. Natural ecosystems of the Wildland Urban Interface are often threatened and under pressure from increasing development. By incorporating native plants into your landscapes, you can help extend habitat and conserve the beauty that likely brought you to the area in the first place.
Zone 1: 5-30′ from structures
Defensible space is an area around a home or other structure that is designed, modified, and/or maintained in a way that increases the probability of the home surviving a wildfire event. All vegetation, whether native or non-native, are potential fire fuel. Through proper planning, you can have both a beautiful native landscape and a fire-wise home. Fire-wise landscapes should also include hardscape elements, such as granite paths, patios, and stone walls. These can act as fuel breaks in-between islands of native vegetation to help slow down or change the path of an approaching fire.
The size of the zones shown above are supported by research into home losses in wildfires, and are consistent with most local regulations at the time of publication. Based on this evidence and current CalFire standards, we show a maximum distance for vegetation modification of 100′ from the house. However, the type of vegetation, terrain, and local regulations may require additional thinning beyond 100′. Contact your local Fire Department for specific requirements.
Native vegetation is often protected by regulations, so do not remove previously unmodified habitat without first contacting your local County planning department for specific limitations and processes.
Recommendations for Zone 1: 5-30′ from structures
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Choose mostly ground covers and small shrubs to 3’ in height, with occasional larger shrubs or trees free of ladder fuels.
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Provide horizontal spacing between planting areas. A good rule of thumb is to create a space twice the height of the adjacent plant groupings (see diagram below). The horizontal space will increase with steeper slopes. These less flammable spaces can include patios, pathways, driveways, walls, or well-hydrated and drought tolerant grasses or low-growing herbaceous plants.
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Avoid ladder fuels by creating vertical spacing. Under tall shrubs and trees, the distance between the understory plant and lowest tree limb is recommended to be 3X the understory plant height (see diagram below). | ||||
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Hardscape: Designing Against Fire – Interrupt the path of fire in the landscape with hardscape elements such as walkways, patios, and walls. See below for more information. | ||||
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Plant “islands” or clusters of native plants to provide habitat for wildlife. Separate these islands with non-combustible pathways or other landscape elements.
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Plant primarily native species within Zone 1 and 2. Native plant species support local ecosystems and wildlife. Click here for information about native plants. | ||||
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A wood mulch such as arbor mulch is ideal in the planting areas, but avoid “gorilla hair” or other finely shredded material. These organic mulches maintain soil moisture, prevent weeds, and help to feed the soil. Between planting areas choose non-flammable materials to break the path of fire.
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California fuchsia, Epilobium canum. Design and photo by Jon Kanagy
Wooly sunflower, Eriophyllum lanatum. Design by April Owens, photo by Saxon Holt/PhotoBotanica.
Planting in Islands
A landscape strategy for fire resilience should consider “islands”, or groupings of plants that are separated by noncombustible elements. These islands, if made up of native plants, will contribute habitat and welcome pollinators, birds, and other wildlife to contribute to area biodiversity. Zone 1 is typically where a house fire is fought, and the landscape should allow firefighters to survey the area and move freely about the landscape.
Grouping of shrubs should be designed from low density to high density as one moves farther away from the house and can be in the range of 75 to 200 square feet, depending upon risk factors such as home hardening, site conditions, other defensible space improvements, and wildfire likelihood.
Islands of native plants create much more habitat than isolated plants. Use Plant Selection criteria to find the most appropriate plants for your garden.
Maintain or remove vegetation adjacent to fences, outdoor furniture, and play structures.
Get creative with breaks between islands of plants – swales and dry creeks are great fuel breaks.
Spacing Between Plant “Islands”
Disrupt the path of fire with “fuel breaks” that provide space between “islands” or groupings of plants. The space between planting areas should be twice the height of the adjacent plants (see diagram), but the space should increase with steeper slopes. Such spaces can include patios, pathways, drives, walls, or well-hydrated and drought tolerant grasses or low-growing herbaceous plants. Be sure to maintain or remove vegetation adjacent to fences, outdoor furniture, and play structures.
Vertical Spacing
In all plantings be sure to eliminate ladder fuels, the condition in which there is a continuous path of fuel for a fire to climb from the ground to a tree crown or roof.
A few larger shrubs or well-spaced trees are acceptable in the Home Protection Zone, but it’s important to provide vertical spacing and avoid ladder fuels.
Make sure your trees are trimmed and maintained to allow for horizontal and vertical spacing with your house and other plants or structures. A good rule of thumb is that the distance from the lowest branches should be three times the height of the shrub or groundcover below.
- If your tree is more than 18-feet high, it is recommended to remove all tree branches at least 6 feet off the ground.
- If your tree is less than 18-feet high, it is recommended to remove all tree branches within the first 1/3 of the tree height.
Trees
- While trees may overhang the roof, place new trees to avoid future excessive pruning to maintain adequate distance of at least 5’, and be aware that it is critical that all debris is regularly removed from the roof.
- Keep tree limbs at least 10 feet from chimneys.
- Minimize ladder fuels that will take fire from the ground into the tree canopy. See the vertical spacing section above.
- Remove dead or dying trees. If you have doubts about a tree’s health, seek help from a qualified professional.
Ground Covers
- An adequately hydrated ground cover can be used to create areas of low fuel between shrubs and beneath trees.
- Ground covers to 12-18” in height can be a desirable part of the landscape, but take care that they don’t create ladder fuels to trees or taller shrubs above.
- While lawns provide little habitat, if a lawn is desired as a play surface, choose drought tolerant native grass options.
- Cutting your lawn to no less than 4 inches high increases drought resistance allowing the grass the ability to regulate temperature and moisture, and form deeper roots.
Mulch
The use of wood mulch is allowed within the Home Protection Zone in planting areas that are separated by non-flammable material.
- In planting areas, 2-3” of composted wood-chips from tree trimmings is highly recommended. It prevents weeds, reduces evaporation from the soil surface, cuts watering needs and promotes soil microbial activity.
- Do NOT use “gorilla hair” or other finely shredded material. It is highly ignitable and may easily blow in the wind while burning.
- Do NOT use rubber or plastic based mulch. Rubber mulch produces very high temperatures and flames when ignited. It ignites easily and burns intensely for a prolonged period. Learn more about the combustibility of different types of landscaping mulch here.
- Between planting areas choose non-flammable materials such as gravel or brick pathways and other “hardscape” landscape features to break the path of fire.
- Keep wood mulch away from tree trunks and flammable fencing.
Hardscape: Designing Against Fire
You can take advantage of multiple hardscaping solutions to protect against fire.
- Create islands of vegetation interrupted by non-flammable pathways, walls, or dry creek beds.
- Stabilize your slope with retaining walls or terracing. These structures can help break up fire-generated winds and stop embers from blowing along the ground.
 Design and photo by Ellie Insley |
 Stone steps and boulders divide a Zone 1 landscape to limit the path of fire. Design and photo by April Owens. |
Irrigation
Proper irrigation amounts and timing will keep plants hydrated. For information about hydrozones (grouping plants by water needs) and smart irrigation systems, please see our Water & Irrigation section.
Environmental Considerations for Planting and Fuel Management
Some native plants are protected by California law. Important California laws for native plant protection are the California Endangered Species Act (CESA), the Native Plant Protection Act (NPPA), the California Environmental Quality Act (CEQA), the Natural Community Conservation Planning Act (NCCPA), and California Penal Code Section 384a. Find more information about these regulations by clicking here.
For more information about these regulations and permits, please contact the Native Plant Program (California Department of Fish and Wildlife) at [email protected].
Erosion
Do NOT remove vegetation down to bare soil. Excessive clearing can lead to erosion, causing slope destabilization. If equipment is needed on slopes, assure that soil conservation practices are implemented.
Endangered/Threatened Species and Migratory Birds
The timing of vegetation management is very important. Birds nest during the months of March to August, so significant pruning and plant removal is best done between September and February. If it is necessary to remove vegetation during bird breeding season, survey for the presence of nests, and if one is found, avoid that area until birds have fledged.
Invasive Species
As part of their vegetation management activities, owners should avoid planting invasive species, and should prioritize removing those that occur. For more information about invasive species, see our section on Invasive Species.
Oak Tree Pruning or Removal
Oak tree pruning or removal may be subject to restrictions and ordinances. Consult your city or county authorities for questions or permits. You can find more information about oak tree conservation in our section on Oak Woodlands.
Zone 2: 30-100′ from structures
The Reduced Fuel / Thinning Zone
The Reduced Fuel / Thinning Zone has a dual function. It serves as a connection with the natural environment, promoting habitat restoration while eliminating continuous, dense vegetation, to decrease the energy of the wildfire. The Reduced Fuel / Thinning Zone supports habitat connectivity and wildfire discontinuity. Do NOT remove vegetation down to bare soil. While larger plants and plant groupings are increasingly important in this zone, attention to horizontal and vertical spacing is still very important.
Zone 2: 30-100′ from structures
Defensible space is an area around a home or other structure that is designed, modified, and/or maintained in a way that increases the probability of the home surviving a wildfire event. All vegetation, whether native or non-native, are potential fire fuel. Through proper planning, you can have both a beautiful native landscape and a fire-wise home. Fire-wise landscapes should also include hardscape elements, such as granite paths, patios, and stone walls. These can act as fuel breaks in-between islands of native vegetation to help slow down or change the path of an approaching fire.
The size of the zones shown above are supported by research into home losses in wildfires, and are consistent with most local regulations at the time of publication. Based on this evidence and current CalFire standards, we show a maximum distance for vegetation modification of 100′ from the house. However, the type of vegetation, terrain, and local regulations may require additional thinning beyond 100′. Contact your local Fire Department for specific requirements.
Native vegetation is often protected by regulations, so do not remove previously unmodified habitat without first contacting your local County planning department for specific limitations and processes.
Recommendations for Zone 2: 30-100′ from structures
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Plant primarily native species within Zone 1 and 2. Native plant species support local ecosystems and wildlife. Learn more about native plants in our dedicated section. With increased distance from the home, larger plants and larger groupings are increasingly appropriate. | ||||||
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The same general defensible space principles apply from Zone 1. Plant “islands” or clusters of native plants to provide habitat for wildlife. In this zone it is still important to avoid continuous vegetation, but pathways between islands need not be inflammable, rather they may be arbor mulch as the distance from the home increases.
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Consider an ecological transition to surrounding wildlands by choosing species of native plants appropriate to the adjacent vegetation community.
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Remove invasive plants. Click here for the list of invasive species. |
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Assure proper horizontal and vertical spacing between lower plants and the limbs of trees above. (See below). | ||||||
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Leaf litter provides many benefits and can be allowed to remain in this zone as part of the 2-3” of organic mulch.
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Groupings of Shrubs
Grouping of shrubs should be designed from low density to high density, and low stature to taller, as one moves farther away from the house. Break up the continuity of vegetation with pathways separating the islands of plants. In Zone 2, arbor mulch is an acceptable pathway material, although non-flammable pathways remain more effective in interrupting the pathway of fire.
 Design by April Owens, photo by Jon Kanagy |
 A zone 2 island featuring foothill penstemon (Penstemon heterophyllum) and deergrass (Muhlenbergia rigens). Design and photo by April Owens. |
Spacing Between Plant “Islands”
Disrupt the path of fire with “fuel breaks” that provide space between “islands” or groupings of plants. The space between planting areas should be twice the height of the adjacent plants (see diagram), but the space should increase with steeper slopes. Such spaces can include patios, pathways, drives, walls, or well-hydrated and drought tolerant grasses or low-growing herbaceous plants. In Zone 2, arbor mulch is an acceptable pathway material, although non-flammable pathways remain more effective in interrupting the path of fire.
Vertical Spacing
In all plantings be sure to eliminate ladder fuels, the condition in which there is a continuous path of fuel for a fire to climb from the ground to a tree crown or roof. Make sure your trees are trimmed and maintained to allow for horizontal and vertical spacing with your house and other plants or structures. A good rule of thumb is that the distance from the lowest branches should be three times the height of the shrub or groundcover below.
- If your tree is more than 18-feet high, it is recommended to remove all tree branches at least 6 feet off the ground.
- If your tree is less than 18-feet high, it is recommended to remove all tree branches within the first 1/3 of the tree height.
Plant Selection
Select climate-appropriate plants. California native plants have evolved over time to thrive in our unique and varied climate conditions. Learn more about California native plants here.
Trees
Many residential areas are located within forests or woodlands, in which mature tree canopies are touching overhead. As long as there are no ladder fuels that can carry a fire from the ground up into the canopy, this intertwining canopy should be no problem. Also note that it is wise to create a break in the canopy at least 30′ from the house to reduce the risk spread to the house if a canopy fire occurs. If there is enough sunlight, lower growing shrubs (to 3’) and groundcovers can be beneficial in these woodlands to provide wildlife habitat. All trees should be pruned to remove dead or dying branches, and lower branches should be pruned to 3x the height above the understory plant.
Ground Cover
- Many native ground covers are available that provide nectar for pollinators and cover for small animals.
- If there are annual grasses or weeds, cut to a maximum of 4 inches in height. To prevent erosion, do not cut to bare earth.
- Assure adequate vertical spacing under trees to avoid the creation of ladder fuels (see vertical spacing diagram).
Mulch
The use of wood mulch is allowed within the Reduced Fuel/Thinning Zone.
- Optimally, wood mulch should not be used in a continuous manner in the landscape.
- Composted wood-chips from tree trimmings are preferred as it prevents weeds when applied as a layer 2” to 3” thick, reduces evaporation from the soil surface, cuts watering needs and promotes soil microbial activity.
- Do NOT use “gorilla hair” or other finely shredded material. It is highly ignitable and may easily blow in the wind while burning.
- Do NOT use rubber or plastic based mulch. Rubber mulch produces very high temperatures and flames when ignited. It ignites easily and burns intensely for a prolonged period. Learn more about the combustibility of different types of landscaping mulch here.
Hardscape: Designing Against Fire
You can take advantage of multiple hardscaping solutions to protect against fire.
- Create islands of vegetation interrupted by non-flammable pathways, walls, or dry creek beds.
- Stabilize your slope with retaining walls or terracing. These structures can help break up fire-generated winds and stop embers from blowing along the ground.
Irrigation
For information about Hydrozones (Grouping Plants by Water Needs) and Smart Irrigation Water Systems, please see our Water & Irrigation section.
Endangered/Threatened Species and Migratory Birds
The timing of vegetation management is very important. Birds nest during the months of March to August, so significant pruning and plant removal is best done between September and February. If it is necessary to remove vegetation during bird breeding season, survey for the presence of nests, and if one is found, avoid that area until birds have fledged.
Restrictions exist that may impact when and where you may remove vegetation. Consult jurisdictional agencies, which may include California Department of Fish and Game and the U.S. Fish and Wildlife Service.
Environmental Considerations for Planting and Fuel Management
Some native plants are protected by California law. Important California laws for native plant protection are the California Endangered Species Act (CESA), the Native Plant Protection Act (NPPA), the California Environmental Quality Act (CEQA), the Natural Community Conservation Planning Act (NCCPA), the California Desert Native Plants Act (CDNPA), and California Penal Code Section 384a. Find more information about these regulations by clicking here. For more information about these regulations and permits, please contact the Native Plant Program (California Department of Fish and Wildlife) at [email protected].
Soil Erosion
Excessive clearing can lead to erosion, causing slope destabilization and potential establishment of invasive plant species. Please consult with a professional experienced in soil conservation and ecological restoration before beginning vegetation removal from slopes.
Invasive Species
As part of their vegetation management activities, owners should not be planting invasive, and consider removing those that occur. For more information about invasive species, see our section on Invasive Species.
Oak Tree Pruning or Removal
Subject to restrictions and ordinances. Consult the Environmental Review Unit for questions or permits. They can be reached at (818) 890-5719. You can find more information about oak tree ordinances in our section on Oak Woodland.
Streams
Restrictions impact activities near the bed, bank, and channel of a waterway. Consult the California Department of Fish and Wildlife for streambed alteration agreements. Click here for more information.
Sources
California Natives (UC Master Gardener Program of Sonoma County)
California Native Plants: Beauty & Many Environmental Benefits (UC Marin Master Gardeners)
Reducing the Vulnerability of Buildings to Wildfire: Vegetation & Landscaping (UC ANR Publication 8695
California Native Plants for The Garden (2006) by C. Bornstein, D. Fross, and B. O’Brien. Cachuma Press.
California Watershed Approach to Landscaping (G3, 2018)
Compost in a Hurry (UC ANR, 2007)
Defensible Space, Fire Retardant Landscaping, and Fire Hazard Reduction (UC ANR, 2020)
Fire Preparation Through the Year (UC ANR, 2020)
Fire Recovery Guide (California Native Plant Society, 2019)
Getting Started with Native Plants (Theodore Payne Foundation, 2015)
Native Planting Guides (California Native Plant Society)
Pruning Tips and Techniques (California Native Plant Society)
Starting a Native Plant Garden (California Native Plant Society, 2017)
