Many months have passed since the catastrophic North Bay wildfires in Sonoma and Napa counties. These historic fires took lives, ravaged neighborhoods and inflicted significant financial damage to both communities and businesses.
It’s inevitable that another fire storm will eventually strike the Bay Area. As a result, every Bay Area Landscape Professional must now consider how they can help their customers create and sustain more fire-resistant landscapes. Mitigating fire risk is the new priority.Mitigating fire risk must now be a priority for landscape professionals. #fire-safeplants Click To Tweet
A history and environment of fire.
With its Mediterranean climate and hilly, mountainous terrain, the Bay Area has historically been affected by wildfire. Yet, given this history and the unique topography of the region, an important question remains unanswered: “What can be done to prevent future disasters like the 2018 Napa and Sonoma fires?”
Unfortunately, there is no one-size-fits-all solution to this significant challenge. But realistic components can include:
- | Improved zoning
- | Strict fire ordinance enforcement
- | Community prevention education
- | Awareness of + integration of more fire safe plants
The burning need for fire-resistant landscape.
Scott Stephens, a professor of environmental science, policy, and management at UC Berkeley, has stated that city officials are often unable or unwilling to enforce strict fire ordinances or safety codes.
He points out that city governments encourage development into wild land areas to expand their tax base. The result is development often “interfaces” with wild land areas that put the inhabitants at extreme fire risk.
Katherine Randolph | Fire Safety Workshop Leader
As fire prevention advocate, Katherine Randolph, shares in her popular Fire Safety Workshops in partnership with FIRESafeMarin, Marin County is particularly vulnerable to fire disaster. This is due to the large percentage of forested and wild land that has been built into.
Fire officials estimate the amount of fire fuel on Mt. Tamalpais has tripled from what it was in 1929. That year, a devastating fire destroyed 117 homes and burned thousands of acres.
Additional factors adding to the increasing risk of fire danger throughout the Bay Area include:
- | Climate change
- | Hotter, drier + longer fire seasons
- | Wildfire behavior affecting urban areas in unexpected + catastrophic ways
The Coffey Park neighborhood in western Santa Rosa is a prime example of these interconnected influences. The devastation there demonstrated that previously designated low-risk neighborhoods are now vulnerable. Therefore, it makes sense that awareness of fire-safe landscaping and building practices must be more vigorously addressed.
So how can a Bay Area landscape professional contribute to improving the fire safety and defensibility of their client’s landscape? The answer may be found in WUI.
What’s WUI and why should you care?
Cal Fire defines “areas where homes are interspersed among wild lands” as intermix zones. The rising number of these environments throughout the Bay Area are called Wildland Urban Interface or WUI zones.
Codes and ordinances have been enacted by most fire districts in California for WUI areas. These codes provide important guidelines for access, water supply and vegetation for most new construction and major remodels.
While new developments must submit landscape management plans to local governments that provide a 30′ clear perimeter around a residence or structure, the thousands of already built homes in the Bay Area present the bigger challenge and opportunity for Bay Area Landscape Professionals. That’s because their landscapes are not optimized for fire defense.Climate change is increasing fire danger risk throughout the Bay Area. #fire-safeplants Click To Tweet
The best offense is a good defense.
Defensible space is essential to improve the opportunity of surviving a wildfire and minimizing damage. This unplanted—or properly planted—buffer between a structure and the landscape around it—or any surrounding wild land—is essential to meet today’s WUI requirements.
Defensible space is necessary to slow or stop the spread of wildfire and protect a structure from direct flame contact or radiant heat. It also helps protect firefighters by providing both a barrier and adequate space for access when defending a structure from spreading wildfire.
As a Landscape Pro, you should have clear and simple goals when planning and installing a fire-safe landscape with compliant defensible space. They should include:
- | Decrease potential fuel
- | Interrupt fire paths
- | Install fire-resistant plants
- | Comply with local fire department WUI codes + ordinances
The good news is, making a landscape fire-safe doesn’t have to be unattractive or cost prohibitive. Fire-safe landscaping can both conserve water and increase property value while improving the aesthetics of just about any location.
Landscape Designer Nancy Roche, with Sonoma Landscape Architecture firm Roche + Roche, often designs rural residential projects that connect to and/or are part of wild landscapes. In her work, she address these key considerations when planning a fire-safe landscape:
- Relationship of residence and landscaped area to wild landscape including:
- composition of wild landscape ecosystem
- transition from irrigated, maintained landscape to non-irrigated wild landscape
- level of maintenance required for both
- Site location, access, slope, aspect, soil + water
- Tree + plant spacing
- Fire breaks including: vineyards, gravel paths, roads, ponds, swimming pools
- Less fire prone plants including CA natives
Nancy Roche | Roche + Roche Studio
Fire-resistant landscape checklist.
As Nancy points out, thorough planning, proper site preparation and use of the right plants will yield a more defensible, fire-resistant landscape. To keep you on track as you address your landscape project, this checklist provides guidance on where you need to focus:
icon-check-circle | Minimize use of coniferous shrubs + trees within 30′ of a structure
icon-check-circle | Avoid junipers + conifers
icon-check-circle | Create hard scape fuel breaks with paths, patios, driveways, rock walls, brick + cement partitions
icon-check-circle | Install drip irrigation
icon-check-circle | Integrate water features including swimming pools, spas, ponds + fountains to reduce fuel volume
icon-check-circle | Use inorganic mulches including gravel, pebbles + rocks
icon-check-circle | Prune trees and shrubs regularly
icon-check-circle | Remove tree branches at least 10′ from structures, chimneys + power lines
Craig Latker, principal of Latker Design Solutions in San Francisco, recommends that his clients use landscape professionals to implement a systematic program of brush and dead wood removal. This is best done in the winter months when there is less spark hazard from chainsaws and when resources are seasonally less busy.
Craig Latker | Latker Design Solutions
Many properties may be too large to be dealt with in one season. Craig suggests starting close to structures and then working outward to the property boundaries.
Invasive, highly flammable species such as Cytisus scoparius | Scotch broom and Spartium junceum | Spanish broom along with native Umbellularia | Bay, should be removed when they are small along with all dead wood and brush.
Craig also recommends integrating high use, hardscape areas such as decks, patios, pools and plazas close to a residence or structure with planting set back.
Use a zone defense against wild fire.
According to the Ross Valley Fire Department, a fire-safe landscape is composed of three concentric areas around a residence or structure. These zones address the required 100′ of defensible space in a WUI compliant landscape. They include:
- IGNITITION ZONE | begins outside of a structure + extends about 5-6′
- DEFENSE ZONE | within 30′ of a residence or structure
- REDUCED FUEL ZONE | lies beyond the home defense zone, extending at least 100′ from residence or structure to property line
It’s important to recognize that greater defense zone widths may be necessary if a home or structure is on a steep slope or in a windswept exposure.
Plants to avoid, remove + replace.
Tiburon Deputy Fire Marshal, Mike Lantier, recommends that certain types of ornamental trees should be minimized or avoided when planning or renovating a landscape.
Mike Lantier | Tiburon Deputy Fire Marshal
He points out that Eucalyptus, Monterey Pines and Juniper should be eliminated completely because the impregnated oils and resins in these species burn explosively. The result of using these plants or trees in a landscape make effective firefighting nearly impossible.
Plant specimens that Mike and other Bay Area fire fighters recommend avoiding include:
- Algerian Ivy | Hedera canariensis
- Bamboo | Bambusa
- Broom | Cytisus
- Cypress | Cupressus glabra + Cupressus sempervirens
- Leylandii Cypress | Cupressocyparis leylandii + Cupressus forbesii
- Douglas Fir | Pseudotsuga menziesii
- Eastern Red Cedar | Juniperus virginiana
- Eucalyptus | Eucalyptus camaldulensis
- Juniper | Juniperus virginiana
- Manzanita | Arctostaphylos hookeri
- Pampas Grass | Cortaderia selloana
- Pine | Pinus
- Rosemary | Rosmarinus officinalis
- Thuja | Arborvitae
- Toyon | Heteromeles arbutifolia
- Wattle | Acacia
Put these fire-resistant plants in your installation.
Fire resistant plants can be the cornerstone of defensible and beautiful landscape. However, all plants will burn if they are poorly maintained.
Therefore, it’s critical to choose fire resistant species, maintain plant health, irrigate with water-wise methods and, as the experts above point out, regularly remove all dead material.
In an ideal world, landscape plant palettes in the fire prone Bay Area should include a majority of succulent species. This includes citrus which has relatively succulent leaves. This planting strategy is practical near the coast in frost free zones but less of an option in areas prone to periodic freezes.
Scott Lewis | Scott Lewis Landscape Architecture
Scott Lewis, of Scott Lewis Landscape Architecture in San Francisco, suggests the use of smaller trees in the 12’—20′ high range such as Acer Palmatum | Japanese Maple and Prunus | Cherries. When used in a fire safe design, they typically will be at or below a roofline. Their smaller canopies also allow for grouping while meeting code requirements of 10’ separation from a structure.
Scott also likes ornamental grasses such as Miscanthus, Sesleria and Bouteloua. They are good choices for massed planted areas at the 12″ to 3′ height, require low-maintenance and are not pyrophitic or fire prone.Are you installing fire-resistant plants for your customers? #fire-safeplants Click To Tweet
Are these fire-resistant plants on your list?
I talk to landscape pros every day about their unique needs for installations throughout the Bay Area. And I often recommend use of some of the fire resistant plants I’ve assembled in the list below.
Integrating them into your project will add both beauty to the landscape and peace-of-mind for your clients.
This is a genus of more than 30 species of succulent, subtropical plants that includes the popular Aeonium hierrense and Aeonium undulatum | Saucer Plant. Leaves are typically arranged on a basal stem, in a dense, spreading rosette that is divided into sections. They are drought-tolerant, low maintenance and prefer full sun.
Agave americana + Aloe Species
Agave americana is commonly called the century plant. It typically lives 10 to 30 years and spreads to 6–10′ with gray-green leaves of 3–5′ long. Give this dramatic plant plenty of room and install it away from foot traffic because the prickly leaves sport a dense spike at the tip that can be quite dangerous. Near the end of its life, Agave american sends up a tall, branched stalk, laden with yellow blossoms, that may reach a total height up to 25–30′ tall. It then dies after flowering.
Ceanothus ‘Ray Hartman’
This CA native is a large shrub with a dense mass of dark wrinkled green leaves. It is covered with deep blue flower clusters in early spring, mostly March to April. It requires good drainage, infrequent watering and can be temperamental, preferring sun to partial sun exposure. C. ‘Ray Hartman’, C. ‘Julia Phelps’ and C. ‘Joyce Coulter’ are all great options for this CA beauty.
Deer say ‘No Thank You’ to Ceanothus hearstiorum. This hardy groundcover is less than 12″ tall but it spreads 6 to 8′ across. It is drought tolerant and grows well in full sun to light shade. It’s one of the more shade-tolerant species of Ceanothus but needs well-drained soil to thrive along with irrigation in the hot summer season. If your installation or landscape design calls for a spreading ground cover that is amazing when it blooms, Ceanothus hearstiorum is great choice.
One of my favorites is Echeveria elegans, also known as the ‘Mexican Snowball.’ This plant is a tough succulent that provides great color and contrast to other darker leafed plants. It’s a perfect solution for inserting in rock walls or any other random crevice you can find in your project.
David Rimer | Hummingbird Tree Service
Epilobium canum is also referred to as Zauschneria californica. Abundant scarlet tubular flowers appear in the fall and this beauty looks best when trimmed after flowering or before new growth begins. It’s attractive to hummingbirds and drought tolerant.
The Lavandula genus is a short-lived herbaceous perennial plant that includes L. stoechas, L. dentata, and L. multifida. Leaves in this species are covered in fine hairs and they contain fragrant oils. The flowers may be blue, violet or lilac and they yield abundant nectar. Both buds and greens are used in teas and as ingredients of high-quality honey. Lavenders flourish best in dry, well-drained, sandy or gravelly soils in full sun. All types need little or no fertilizer and good air circulation.
There are many varieties of these drough-tolerant, fleshy leafed ice plants. Mesembryanthemum are used often as ornamental plants for their showy flowers which are very long-lasting and quite vibrant. They prefer well-drained soil but can grow in heavy clay too as long as they are in full sun.
Mimulus aurantiacus is a showy perennial and CA native has abundant apricot colored blossoms that will attract hummingbirds. Occasional summer watering will extend the blooming season. It’s drought tolerant and does best in full sun to part shade.
Senecios are spreading succulents from South Africa that grow to 12″-18″ inches tall with 3″-4″ long, blue gray pencil-like fleshy leaves. They bloom with colored flowers in mid-summer and form a dense carpet of angled upward leaves as they spread. They are hardy ground covers that prefer full sun.
Want to know more?
As both a grower and a plant broker, we’re ready to work with you to provide just the right fire-resistant ground covers, grasses, shrubs and trees that will make your project a success. We can also provide an Estimate for one item to an entire installation just by attaching your plant list to our convenient online estimate form.
Contact any of our experts online at Pacific Nurseries or just call 650.755.2330.
Want to know what’s in bloom, fire-resistant and looking great right now for your project? Our Prime Plant List is an easy-to-use summary of items we have in limited availability and prime seasonal condition. All of them are available for immediate purchase or delivery.
What are you doing to minimize fire risk in your project?
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