Discover your wildfire risk and protect your family with a safely wild yard.

Dear Avant Gardener, About leaving fallen wood lying in place: Many California oaks are dying here, most say from drought. We have a lot of these trees and a lot of dead branches. I’m afraid of fire — this material really is combustible. If we had a fire and had to leave the house we would have to drive through these dead and living dry trees. Also, insurance is harder and harder to get. About three years ago our previous carrier did not renew policies in our zip code; we applied for a policy to 18 insurers and only 1 took us. This is a common story in Southern California. What are your thoughts on fire? — Early Subscriber, La Cañada Flintridge, CA

Great question! I’ve received many comments on social media about the fire risk of leaving snags and leaves, as well as fallen branches. I wasn’t sure how to answer, because there is a lot of fear and misinformation out there on the topic. So Zoe and I interviewed Adrienne Edwards, author of the beautiful and well-researched recent book, ​Firescaping Your Home.

Check your wildfire risk

Let me cut to the chase for readers in other regions: The most surprising fact I learned from Edwards is that everyone should be cognizant of their wildfire risk and how to mitigate it. She said, “Just because you’re in a wet environment doesn’t mean it couldn’t burn, too. I’d like to reinforce the fact that this summer, when Canada was burning, Louisiana was also burning. And the most deadly wildfire in U.S. history happened in the late 1800s in Peshtigo, Wisconsin. We all need to think about fuels.” [All of you, please check your fire risk at the link below.]

The wildfire risk in La Cañada Flintridge is higher than 91% of communities in the United States, but even there the risk varies dramatically from lowest to highest risk, depending on the exact location of your property. If you haven’t done one already, you’ll want to do a comprehensive review of your property and take steps to mitigate risk. You'll find that man-made structures pose a much greater risk than your landscaping.

Canopies catch embers — in a good way

Instead of a threat, those oaks around your house offer protection — if properly pruned. Edwards and her co-author Rachel Schleiger list 640 resilient native plants in their book, and she told us oaks are her favorite tree for wildfire country. As Los Angeles landscape designer Cassy Aoyagi writes, talking about her yard pictures below,

Many people see danger in tree canopies. Palms and cypress might combust, however, fire scientists have trained us to value effective tree selection and placement as critical fire mitigation strategies. Thick trunks and branches won’t easily ignite. The oak’s dense canopy resists penetration by flying embers. Even the hackberry’s airy canopy can delay ember travels. Each year, we prune back branches that extend toward the structure of the home, in accordance with the defensible space principles that experts advise. — ​Flora Magazine​

Snags, maybe; fences, no

With respect to dead branches and dying trees, “you need to think about the horizontal and the vertical distribution of fuel,” according to Edwards. “You can think of [dead trees] in terms of a forester. If it’s so tall and unstable that it’s going to be a risk, then lay it down and create habitat…. As long as you don’t have too much of it on the ground and it’s not too close to structures, there’s no reason not to let it decompose in place.

“A bigger concern for me than having the occasional snag in fire country on your property is the use of wood fences, which are everywhere in California. And those are railroad tracks for shedding embers and igniting houses,” Edwards told us. “There are many instances where … only a couple of homes were burning by the time everybody was evacuating and then, over the course of a day, the fire just went from house to house along those fences.”

Insurance — theory and practice

As for insurance, inspectors “are supposed to take into account how much clearing you have done, whether you have, first of all, … fire resistant structures on your house, and secondly, what you’ve done with vegetation,” Edwards explained. “The type of roofing you have, whether your eaves are closed, whether you have ember-resistant vents are all super important, because, of course, your house is more ignitable than any of the vegetation … because it’s all dead wood.

“In terms of clearance in the safety zones, you certainly get credit for having the zero to five foot areas next to your home completely cleared," Edwards continued. "No vegetation and no combustibles should be in the zone during fire season. If you’re in a really high fire risk zone, say, on a steep slope, that should be at least 15 feet. Research has found, ... there’s a zone up to about 30 feet where you want to clear and make it ‘lean, clean and green.’ So you keep your plants properly hydrated, not over watered, with infrequent deep watering. You keep it pruned. You make sure the vegetation isn’t too thick, and there are no dead branches. And not too much organic materials.

“But the problem when it comes to the insurance commissioner and insurance inspectors is that … they’re not usually gardeners, and they’re not usually fire experts. And so we have a disconnect between the regulations and the people on the ground saying, ‘Oh well, I can’t insure your home because you have trees on your lot.’ We have a long way to go to have a more subtle understanding and interpretation of what is safe in fire country," Edwards said. "A lot of legislators are trying to think about how to better address it, because people need to have home insurance. ... The certification process for being able to assess homes in wildfire country with wildfire risk needs to be changed and those folks need better training.”

For now, get the book!

— The Avant Gardener

Why, How, Wow!

Why?

Wildfire risk and insurance policy are indeed closely linked. More than half of all U.S. buildings are in designated disaster zones and these areas continue to grow more quickly than elsewhere; wildfire risk is growing largely through expansion in the wildland-urban interface (WUI), according to Firescaping Your Home.

For decades, distortions in federal and state insurance markets have suppressed rates, enabling a mass migration to hazardous areas. … The population of Florida, which suffers more hurricanes than any other state, grew more than twice as fast as the rest of the country did between 2000 and 2020. … Even more striking, the population in areas most prone to wildfires grew by 160%.

While Americans are moving to risky places, climate change is making them riskier. Now private insurers are sounding alarm bells. Firms are writing fewer policies in vulnerable areas, and are pulling out of some states altogether. — ​The Economist

How

It’s easy to check your property’s wildfire risk, and you may be surprised. I discovered that our Florida island community — where hurricane and flood risk is severe — also has a medium risk of wildfire, higher than 64% of communities in the U.S. I’m evaluating my property — house and yard — to find easy ways to mitigate that risk. Please check your risk by searching for your community at ​WildfireRisk.org.​

I’m going to be sharing more from our interview with Adrienne Edwards in the coming weeks. In the meantime, here are her top three recommendations for firescaping:

1. You have to provide habitat. Outdoor spaces are not living rooms, where you arrange furniture at a whim. If you can’t hear anything going on in your yard, then you need to change your landscape. There are lots of ways to do that, even in small spaces.

2. Get rid of the foundation plantings. You can have spring ephemerals, but get rid of the foundation plantings. That’s a no-no.

3. Know your plants. You should be able to look outside and you can almost see if a plant is thirsty. Native plants can withstand an amazing amount of heat and drought. But plants that are really stressed have dull leaves. They kind of wilt a little bit, and you can see that in the landscape. If you have watered appropriately, very early in the morning, not when we’ve in the middle of a heat wave, deeply and infrequently, those plants will be fine. And all you have to do is reduce the dead fuels around them.

Wow!

Native landscapes are beautiful, as well as fire-resistant. As Cassy Aoyagi writes about her fire resistant yard,

Every imaginable chaparral shrub wraps our property. We host no combustible, invasive foliage here! Our hedgeline serves up an ever-evolving visual feast of our favorite blooms, fragrances, tweets, and berries. Sunny yellow California flannelbush (Fremontodendron californicum) kicks off the show in spring, followed by California lilac (Ceanothus ‘Frosty Blue’), Nevin’s barberry (Berberis nevinii), and Catalina cherry (Prunus ilicifolia ssp. lyonii). The show never stops. — Flora Magazine

Related Resources

• Curious about the beautiful yard pictured here? Read ​Fire-Resistant Landscaping.​

• Incredulous how moist areas can catch fire? See this Scientific American article about wildfires raging in Colombia's ​diversity hotspot.​

• Ready to protect your family? Order ​Firescaping Your Home.​