361 Defensible Space Landscaping Tips

We examine the wildland-urban interface and its growing wildfire risks for homeowners, particularly in fire-prone areas like California and other western states. We talk about the concept of hardening your landscape from the Ember Ignition Zone with insights from Kevin Marini, a UC Defensible Space Advisor. He highlights the importance of maintaining clear spaces around homes and managing vegetation in three defensive zones.

Today, it’s Episode 361, Defensible Space Landscaping Tips. It’s the Garden Basics with Farmer Fred podcast, brought to you today by Smart Pots and Dave Wilson Nursery. Let’s go!

Pictured: A Landscape with Defensible Space (Photo: FiresafeMarin.org)

 Links:
Subscribe to the Beyond the Garden Basics Newsletter https://gardenbasics.substack.com

Smart Pots https://smartpots.com/fred/
Dave Wilson Nursery
HeirloomRoses.com (with the FRED discount link)

Other links mentioned in today’s podcast:

The Dance of Defensible Space, by Kevin Marini
UCANR Fire Network: Creating a Defensible Space
U. Nevada-Reno: Mulch and Flammability
CalFire Demonstration Fire Video
IBHS Research Center Ember Storm Test Video
FireSafe Marin
CA Native Plant Society list of fire-resistant plants

More Wildfire Protection Tips :

Utah State University
University of Nebraska-Lincoln
Vail, Colo.
Ashland, Oregon
Minnesota/Wisconsin
Fort Worth, TX
British Columbia, Canada

Got a garden question? 

• Call or text us the question: 916-292-8964. 
• E-mail: fred@farmerfred.com 

Thank you for listening, subscribing and commenting on the Garden Basics with Farmer Fred podcast and the Beyond the Garden Basics Newsletter.

Chapters

• 1:41 Defensible Space Landscaping Tips Pt 1
• 22:37 Smart Pots!
• 24:32 Defensible Space Landscaping Tips Pt 2
• 42:25 Dave Wilson Nursery
• 43:41 Defensible Space Landscaping Tips Pt 3
• 1:03:47 Want to Leave Us a Question?

Transcript

361 TRANSCRIPT Defensible Space Landscaping Tips

Farmer Fred:

[0:00] Garden Basics with Farmer Fred is brought to you by SmartPots, the original, lightweight, long-lasting fabric plant container. It's made in the USA. Visit SmartPots.com slash Fred for more information and a special discount. That's SmartPots.com slash Fred.

Farmer Fred:

[0:20] Welcome to the Garden Basics with Farmer Fred podcast. If you're just a beginning gardener or you want good gardening information, well, you've come to the right spot. In this episode, we dive deep into the concept of the Wildland Urban Interface, the WUI. It's a critical area where developed residential areas intersect with undeveloped wildland vegetation, and that's often a hotspot for wildfires and destructive home losses. With a staggering amount of housing units situated in fire-prone zones, particularly in states like California, understanding how to protect our homes becomes essential. We talk with Kevin Marini. He's a University of California Cooperative Extension advisor who specializes in landscaping strategies to enhance fire safety. His extensive experience as an arborist and as a defensible space educator make him an ideal guide as we navigate the complexities of yard maintenance in these high-risk areas. Today, it's episode 361, Fire Safe Landscaping Tips. We're podcasting from Barking Dog Studios here in the beautiful Abutilon Jungle in suburban Purgatory. It's the Garden Basics with Farmer Fred podcast, brought to you today by SmartPots and Dave Wilson Nursery. Let's go.

DEFENSIBLE SPACE LANDSCAPING TIPS, Pt. 1

Farmer Fred:

[1:43] Are you familiar with the wildland-urban interface? It's the area where houses meet or intermingle with undeveloped wildland vegetation. It's a focal point, especially for wildfires and the destruction of homes. And this wildfire urban interface areas are particularly widespread in the eastern United States, reaching a maximum of 72% of land area in Connecticut, for example. Now, here in California, we have the highest number of housing units in what's called the WUI area, 5.1 million homes. And that translates to more than 11 million Californians who are living in a wild urban interface, a wildfire urban interface. That means more than a quarter of the state's population is living in a high fire hazard zone. So chances are, and if you ever looked at your insurance bill, you probably already know where you lie as far as wildland urban interface areas, because your rates very frequently are based on that.

Farmer Fred:

[2:49] So you may be thinking, OK, so what do I have to do around my home so that no major problems happen if you live in a wildland urban interface? Well, we're going to tell you about that today. But I'd also like to point out that burning embers are the cause of making the wildland urban interface a much, much bigger area. And I hark back to 2017 in October and the Tubbs Fire, which broke out north of Santa Rosa, which is north of San Francisco, near the mountains. And in that mountainous area northeast of Santa Rosa, that fire broke out. But it created such a windstorm from this fire, there were burning embers, I call them burning pieces of wood, that flew more than a mile westward across a major freeway and into a suburban development of Santa Rosa itself - Coffee Park, where something like 1,200 homes burned, and they were nowhere near a forest. So even though you may see mountains in the distance, don't think you're safe. So getting back to how we protect our home, how do we protect our yard? Let's talk with Kevin Marini. He's a UC Cooperative Extension advisor. We've talked to him in the past about trees and soils because he's a certified arborist. He's a Master Gardener Coordinator, and he's also the University of California Defensible Space Educator. So he is very familiar with this whole idea  of protecting your yard and not necessarily putting in fireproof plants, because as he points out, really, there's no such thing as a fireproof plant. And even though there are plants that you may think are fireproof, well, depending on how you've treated them, they may be, shall we say, dead on the inside and just be waiting to burn because of the way you prune them. We'll get into that. He has a wonderful handout called The Dance of Defensible Space.

Kevin Marini, it's a pleasure for talking with you again. And when it comes to protecting your home from wildfire, it begins in the yard. And in the past, when we've talked about building defense zones that are fire resistance, we've talked about zones one, two, and three. But lately, there's been a new zone added to that, and that's called the zero zone. And what goes on in the zero zone?

Kevin Marini:

[5:08] Well, hey, first of all, thank you so much for having me back on your podcast. I really enjoy this opportunity to do some education and outreach via this medium. I do a lot of talks in person and I do defensible space consultations on site. But being able to reach a huge audience like this is a treat. So first off, thank you for having me. So yeah, I've been teaching a lot about defensible space over the last two years, really for a longer time than that, but really focused  in on it the last couple years. And with that has come this new zone, Zone Zero, as you refer to, called the Ember Ignition Zone. What's interesting about this zone is it's actually not law yet.

Kevin Marini:

[5:51] So a lot of people are paying attention to it because it's likely to become law soon. As of right now, they're trying to work on some of the language and figure out exactly what the zero to five area outside your home and other structures should look like. But one thing we know for sure is that, as you mentioned, embers are the driving force here. And what CAL FIRE says is 85% to 90% of homes that burn down, burn down from embers flying in. They catch things around the home on fire, which then leads to the house burning down. So this is super important because a lot of people I talk to think that a wall of flame is going to be coming at their house,  that actual huge flames are going to be burning down their house. Actually, it's these embers that are flying in. And let's be honest, they're little tiny pieces of burning material that sometimes fizzle out in the air, sometimes fizzle out in your lawn, but sometimes catch something on fire that burns your house down. So obviously, we got to pay attention to the zero to five feet clearance zone. I tell people, go home, take a measuring tape, put it out to five feet and walk around your home and your structures.

And it's not just your home, you may have a barn, you may have a shed. There's other structures as well to consider. And when you start doing that, you notice very quickly that you have some flammable stuff around your home that you probably should pay attention to. So, yes, I believe that's a great place to start.

Farmer Fred:

[7:28] Yeah. And it's not just plant material either. I have neighbors here in suburban purgatory who have seen their insurance rates go up because after an inspection, they were cited for piling up too much stuff, too much of their household goods or cardboard boxes against the side of the house.  And they had to clear them off immediately if they wanted to keep their insurance. 

Kevin Marini:

[7:53] Yeah. And I think that's often overlooked, right? Because people are paying attention to vegetation more so than anything when it could be that recycling bin full of cardboard or newspaper that catches the embers and starts the fire. I always point out things like outdoor furniture. You know, some of our outdoor furniture materials are extremely prone to ignition, right? Some of the cushioning, some of the material, the chairs and benches are made of. And also, I always think about this as a father. We used to have a play structure for our children right outside the house because you want it close by so you can look out the window and watch your kids. Well, a lot of those play structures are bone dry, right? So, I think you just bring home a very important point. That zero to five, that ember ignition zone is anything that's flammable, whether it's a plant, a piece of furniture, or cardboard or newspaper, believe it or not.

Farmer Fred:

[8:51] I know we're going to talk a lot about plants here, but think of the things you can't see that are flammable around your house. Like if you haven't cleaned out your gutters, it could be filled with tree debris that could start a fire. It could be poorly vented homes where the vents are too big and can allow those embers to fly into the attic for example. So there's a lot of checking on that you have to do on the house itself. But in the yard itself, That zero zone also means not even five feet of wood mulch on the ground.

Kevin Marini:

[9:23] Yeah, that's hard to take, especially for people like you and I who love mulch.

Farmer Fred:

[9:27] Well, we should say wooden mulch, like bark mulch. I would think five feet of gravel would be okay.

Kevin Marini:

[9:34] Well, yeah, I think if Cafire could write the book, they would love to see five feet of rock around every structure. But of course, that's not reality for a lot of folks. Now, we have to remember that we find ourselves in this situation because for 40, 50 years, the very foundation, pun intended, foundation of landscape design was to put foundation plantings all around our house, right? So, we have, in a sense, grown up here in the state of California with shrubbery all around our homes. And so, this isn't an easy fix for a lot of folks. A lot of people. I talked to a woman who had 60-year-old beautiful camellias all around her home that the insurance company was asking her to remove.

 So, in a lot of cases, there's emotional problems when it comes to getting rid of beautiful shrubs and trees, sometimes maybe with sentimental value, for example. But it's also the aesthetic appeal. It's hiding the area around your home, giving people privacy. I grew up with juniper shrubs all around my childhood home. We would pick those juniper berries and have wars in our neighborhood. And now I think back, I think that was the most fire hazard situation possible, right? Just the most flammable shrub that we pretty much know of, all around, surrounding a home. And so we find ourselves in a unique situation now where things that we used to value, such as those foundation plantings, now have to be rethought and potentially completely removed.

Farmer Fred:

[11:09] And especially the dead material that some plants can produce. And that's not just in that zero zone, the zero to five foot area, but in the next zone, which goes from five to 30 feet. There's a lot of plants that may look green on the outside, but inside they may be very dead.

Kevin Marini:

[11:25] Oh, yeah.  And this is one of the difficult things that I see all the time in our mainstream kind of landscape maintenance world. There is a lot of hedging and shearing of plants. And I don't mean like plants that you normally think of as hedges, like a boxwood hedge, right? Now that is kind of okay to hedge because they do pretty well in that situation. But in this day and age, a lot of landscape maintenance folks hedge and shear everything. And so you end up creating plants that aren't resilient to fire whatsoever. When you open them up beyond that little surface green area, you end up with dead material in the middle. I call them ‘ember catchers’. And I say that because if the plant was pruned naturally or allowed to grow to its natural form, it would not be an ember catcher, right? So this is a specific type of pruning that is leading to more of a fire hazard rather than fire safety. And so, yeah, I think looking at anything that is hedged and sheared on your property and really putting your hands in there and pulling it apart and peering in there and seeing what's going on in there will be really important for everybody to understand because as those embers come flying in, that's just the perfect spot for them to land.

Farmer Fred:

[12:50] Explain when people hear the term fire ladders, what does that refer to?

Kevin Marini:

[12:54] Fire ladders generally refer to vertical fire ladders, which is where you have, say, an herbaceous perennial underneath a medium-sized shrub, underneath a small tree, underneath a really large tree. And like I said, our landscape design for decades has been to layer plants and to get different textures and a different feel for our landscapes where you have these different sized plants and different colored foliage. That's been the plan. And now that's coming back to bite us because those ladders allow embers to catch fire that small plant  and that flame go quickly up into larger plants and eventually up into trees. When we get fire into trees, we have problems because that's where you get even more ember cast.

Kevin Marini:

[13:47] That's when embers are just spitting out of the top of those trees. Low fire close to the ground, believe it or not, Calfire kind of refers to that as good fire because it has a rejuvenating effect. And as long as it's not getting up into the canopies of trees, then we don't have a lot of ember cast going on. So the main fire ladder is that vertical path up into trees. However, there's another path that we have to be really aware of. And that is more of a horizontal path, a continuous line of vegetation. And so a lot of folks will,  on the sides of their driveways, for example, have a whole line of continuous vegetation stretching, you know, 50 yards, for example. Well, what happens is all it takes is those embers to get into one area and start a fire, and then it has a path all the way to your house or, again, to other vertical fire ladders. So it's not just those ladders that lead the fire up into trees. It's also the continuous vegetation without spacing in between that lead to that path of fire.

Farmer Fred:

[14:59] And gardeners, if there was one disease most gardeners have, it's ‘plant-itis’, where they must plant something. “I’ll find room for it. Don't worry”. And in five years or less, they have a jungle. And gardeners don't like to move because, heck, they've developed that property with so many plants. It's their haven. And they're living in a jungle. And that jungle, unfortunately, now, if it's in that five foot to 30 foot zone, is a fire trap.

Kevin Marini:

[15:28] Yeah. So the five foot to 30 foot zone, which, you know, the traditional defensible space zones are zone one, five to 30, and zone two, 30 to 100. And now, of course, we're going to have this zone zero, that's the zero to five. So the five to 30 is commonly called the lean, clean, and green zone. And so this is where things immediately get funny because here as I'm representing the Master Gardener Program, during the drought years, our messaging was what? It was remove those lawns, put in drought tolerant plants, use a ton of mulch, right? And now that messaging is basically the opposite. We've had to say, look, due to fire, having a little bit of irrigated turf around your home is a nice buffer for those embers coming in. So have a little bit. We now have many, many different types of sods and grasses that are more drought tolerant than the sods of the past. And so there's better options as far as drought tolerance or water efficiency, let's say.

Kevin Marini:

[16:37] But now we're saying, yeah, leave a little bit of lawn around your home for fire protection. And the mulch thing is very difficult because mulch has so many benefits. And we don't want to tell people not to use mulch. What we want to tell people is use it wisely, right? So depending on where you live, what fire zone you're in, and kind of what your defensible space situation is, you may be able to use a lot of it. You may only be able to use a little bit. But the one thing for sure is they have done study after study on the flammability of mulch. There's a great study out of the University of Nevada, Reno, that looked at all different types of organic mulches and their flammability. And what they do is they put these mulches down and they say, okay, how quick are these to ignite? If they ignite, how tall is the flame length?  If it has a huge flame length, how much radiant heat is it putting out, right? So, if a mulch is quick to ignite, has a huge flame length, puts out a ton of heat, guess what?

 That's the one you want to avoid, right? And so, if it's not so quick to ignite, and even if it has a small flame length or smolders and doesn't put out a lot of heat, then it's considered roughly fire-wise, okay? And so what they found was that the most widely used organic mulch in the state of California, which we know, and many people know, as gorilla hair,  which is shredded redwood and cedar.

It is the most flammable by far, by leaps and bounds. And so sometimes I feel like I can just look at that stuff and it would catch fire. On the other end of the spectrum, you have something called arborist wood chips or wood chips that come out of the back of tree trimming company trucks, right? The stuff that was usually a mix of green and brown material, it actually kind of starts to compost in there. There's usually a lot of moisture from the green material from the live tissues of the trees. And so that material they found is actually the most resistant to ignition, a tall flame length, and radiant heat. So if you're going to use organic mulches, use the arborist wood chips if you have access to them and it's doable for you aesthetically. I know a lot of people want mulch to look a certain way. We have a lot of options of kiln dried wood chips out there that you can buy in bulk, and they're all dyed, right? There's some that are dyed black. There's some that are dyed brown. There's some that are dyed kind of an orangey color. And so some people are choosing mulch just based on aesthetics. And I understand that. But if you're in a fire zone where you live next to one of these wildland-urban interface areas that you were talking about, the wildland-urban interfaces, I would recommend, if you're going to use organic mulch, to go with the arborist wood chips.

Farmer Fred:

[19:27] Yeah, and I would avoid that gorilla hair, which is the smallest form of wood chip mulch that you can get. It's very stringy looking. I remember when the new post office went in in Herald, California, and of course, I was assigned to help in the landscaping. And somebody made the mistake of buying gorilla hair mulch for this public area. And I think it was about two weeks later when they found a smoldering little fire going on in there because somebody tossed a cigarette in there.

Kevin Marini:

[19:57] There you go. Yeah. That's all it takes. That's all it takes.

Farmer Fred:

[20:00] Yeah. And basically that was the gorilla hair mulch that ignited. Definitely bigger wood chips are better than that. I noticed in that University of Nevada Reno study of the flammability of mulches. I would definitely not use shredded rubber or pine needles for mulch that has the highest rate of temperature, rate of spread and flame height.

Kevin Marini:

[20:20] Yeah. And then a lot of that rubber mulch is used around play structures, to kind of protect kids if they fall off the play structure. So not only is the play structure itself prone to being kind of dry and made of wood and being able to ignite, but you also have this mulch that's used a lot around them that is extremely flammable. And when it does get going, it burns very, very hot. And so, yeah, I think that we find ourselves in a situation where we have to really think through our use of mulch and use it a little bit more judiciously than maybe we did in the past where it was like, hey, get 15 yards and spread it everywhere, right? And the times have changed a little bit since then as far as our messaging goes.

Farmer Fred:

[21:06] I was surprised to see pine needles right behind shredded rubber as far as the danger of combustion goes. So, yeah, avoid pine needles and also shredded western red cedar.

Kevin Marini:

[21:18] Yeah. Now, the pine needle thing is interesting. So pine needles and oak leaves, you know, they get a bad rap as far as I'm concerned living up here in the foothills. A lot of people are always shocked to learn that I love pine needles and oak leaves as a compost constituent. But I don't want to start going down that road because I can talk composting for 10 hours. So, but pine needles, in nature, you have that top layer of kind of the fresh layer of dried out pine needles that is very easily ignitable. But if you actually walk through a mixed conifer forest area, what you find is there's a duff layer, and there is some pine needle material on top, but very quickly, it turns to kind of a duff that sometimes can really hold a lot of moisture for a long time. Now, by this time of year, in fall, it's all dried out. But it's pretty amazing how it does hold moisture pretty well for a good portion of the season. So what that study was doing was a lot of people will rake off pine needle mulch from around trees and then use it somewhere else. And so it's strictly just the real top layer of dried out pine needles. And that absolutely is to be avoided. I agree.

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DEFENSIBLE SPACE LANDSCAPING TIPS, PT. 2

Farmer Fred:

Let's get back to our conversation with University of California Cooperative Extension Defensible Space Consultant Kevin Marini. And we're talking about exactly how much space do you need between plants or between planted areas in order to defend your home from a wildfire. Let's go back and talk a little bit about spacing plants in that 5-foot to 30-foot zone. Obviously, it would be best to space the plants individually or in clusters and include hardscaping too, like walls or patios or pathways. How wide should a pathway be?

Kevin Marini:

[25:12] Good question. So a lot of times you see language such as ‘plant in the 5 to 30 zone in clusters, in islands’, like what you're talking about. And what's recommended is a three foot zone, at least. Of course, you can go farther out. But a three-foot buffer is a good rule of thumb between these clusters of plantings and other clusters of plantings. And within that three-foot area,  you want to use a completely safe material, something like rock mulch or DG (decomposed granite), for example. Or, like you said, hardscape, so flagstone or something like that.

 So that way, if embers fall into this little island of plants, which, again, you could be using mulch in that island, that is less likely to quickly spread to other areas. It's kind of a way to compartmentalize your landscape so that if embers come streaming in, it kind of burns just this area without spreading to the whole area. And so something as simple as a retaining wall can be the difference between your house burning down or not, right? Because a large retaining wall, three, four feet tall, could potentially intercept those embers coming in. Also, if you have landscape vegetation that's caught fire, it would meet up eventually against that retaining wall and be put out or burn out, hopefully. And so, yes, I think everything you said is correct. You're spacing out the plants both vertically and horizontally. You're planting plants in areas and leaving space between those areas. So not just between the plants, but between areas of planting. And then you're utilizing hardscape wherever you can to break up areas and kind of give yourself little mini fire breaks all over.

Farmer Fred:

[27:10] I'll have a link in today's show notes from this, the video that Cal Fire put out that they called a demonstration burn, where they built two little homes side by side, one with normal landscaping and normal hardscape; and the other very much hardened off to try to slow down the progress of aggressive burning embers. And the one thing I noticed about the house that burned down in 12 minutes versus the other one that never caught fire was,  besides the fact they had mulch piled up next to the house, they also had a wooden fence. And people forget that wooden fences can burn, which goes back to what you're talking about, rock walls and gravel walkways and things that don't catch fire.

Kevin Marini:

[27:55] Yeah. Yeah. So CALFIRE is the mandated entity to do official defensible space inspections. So no one else besides fire personnel do official defensible space inspections. Through UC, I do defensible space consultations and I do that on purpose. I use that word rather than inspection on purpose. And so that's an important resource for people, But, yeah, I think that they would love to see all wood fences that are close to homes or that lead to structures swapped out for, you know, ornamental iron. That would probably be ideal. But some sort of other fencing type that won't catch fire and lead the fire along the fence to a potential structure or another area that isn't hardened.

Farmer Fred:

[28:47] Yeah, this is great information if you're buying a new home somewhere in that wildland interface urban area and there's nothing there and you can get the hardscaping in first and then plant accordingly.

Kevin Marini:

[29:03] Yeah, yeah. And I think there's a lot of talk about using certain palettes of plants to create a fire resilient landscape. So, you know, traditionally,  these have been called fire wise plants. And the one thing that we know for sure is that every plant burns eventually. Right there's definitely a spectrum so you know if you have  a couple little succulents out in front of your house, they are are less likely to ignite and become a problem, as opposed to a mid-sized shrub, especially a juniper. So there's definitely a spectrum. But the idea that you swap out all of the plants in your landscape with quote “firewise plants” is really just a myth. I mean, that is not something that anyone in the fire world is recommending because it's not the species itself. It's how it's maintained and then how you organize your landscape that either gives it some resilience or makes it a hazard. I love how lavender is on almost every firewise plant list, right? When you go buy a one-gallon lavender at the nursery, Yeah, it's pretty firewise. It's nice and lush. There's no dead stuff in it. You can imagine embers being thrown at it and not igniting.

Kevin Marini:

[30:25] And so, yeah, sure, a one-gallon lavender, when you plant it, the first season is firewise. But we all know, well, maybe not “we all”, I guess I'm talking about gardeners know, that soon lavender grows and gets woody and starts accumulating dead stuff, right? And I've seen some plants that I would absolutely characterize as a fire hazard rather than a fire-wise plant. And so, again, that illustrates that this isn't about the species itself. It's about,  how is it going to be maintained? And is it going to be under something or near something where it leads to this path of fire?

Farmer Fred:

[31:05] We talked about clustering plants and spacing plants. And I would think that when you put in larger plants, the shrubs and the trees, I wouldn't go for the minimum space that they recommend. If they say a tree has a 30 foot spread, you would definitely want to plant the next tree over - if it's the same variety - more than 15 or 20 feet away. Because you want that space between the plants so that it isn't tree touching tree touching tree, then a tree touching a roof.

Kevin Marini:

[31:37] Yeah, that's a really great point. Because of course, people usually abide by the spacing that they see on the plant label, or they read it in the book, or they read online. And it may be different depending on where you live, and how your defensible space zones are organized and all of that stuff. And so you're totally right, there has to be additional thought or at least consideration. At this spacing, I'm going to have these branches touching each other eventually. And I need to have them farther apart than that. So the traditional spacing recommendations may not hold true for your landscape nowadays if you live in one of these wildland-urban interfaces, right?

Farmer Fred:

[32:16] Yeah, I noticed that CAL FIRE even recommends that you keep your trees trimmed so that the closest branch of a tree has to be greater than 10 feet away from a chimney. 

Kevin Marini:

[32:27] Yeah. In fact, much of the defensible space zoning,  whether you're talking about a tree in the 5 to 30 or even in the 30 to 100, most defensible space recommendations say limb those trees up 10 feet. Okay. But here's the big caveat. As an arborist,  their  language is limb trees one-third of their height or 10 feet up. So if you have a 12-foot tree you don't limb it up 10 feet because then you'll end up with a little two-foot tuft of vegetation at the top, and the tree will not like you for that. And so, it's either one-third or 10 feet, depending on the size of the tree. And that's really important because I've seen some folks really do some damage to trees, limbing them up a little bit too much when they're young. They don't like that very much at all. And so, yes, that's important to say that in both zones, you're looking at trees very carefully and making sure those limbs aren't on the ground or aren't touching each other. Now, beyond that zone we've just talked about, the 5 to 30, the lean, clean, green, we get to the next zone, 30 to 100.

And the kind of mantra for that is reduced fuel zone. And so this is important, especially in areas that are more rural, where people may have an acre or two or someone like me who has seven acres. That area is your main interface with the wild land just beyond it. And so reducing the vegetation in that area is imperative to making sure that, again, you're not contributing to fire spread. If embers get in there and you haven't done any work, then you can actually increase the number of embers that are coming out from that area rather than getting that fire to decrease in its severity. So just to recap real quick -  Zero to five, ember ignition zone, five to 30, lean, clean, and green, 30 to 100, reduced fuel zone. And everything we've talked about, in a sense, applies in all those zones, depending on the situation. So I live in the foothills, and guess what? I live on a hill. So my property  slopes down. So fire, we know, runs uphill pretty darn fast. So the downhill side of my home in a sense is even more important or a higher priority than other sides of my home because it slopes down to a road. Roads are notorious for starting fires and that fire can rip up to my home very quickly if I haven't done the work.

Farmer Fred:

[35:16] So what is your first line of defense?

Kevin Marini:

[35:18] My first line of defense is an irrigated area where I have fruit trees, if you will. So I have a lower pasture that's up from the road that dries down, but of course the trees are limbed up, there's no fire ladders in that area. I've done the work on that in that respect, but still because of the dead native and non-native vegetation on the ground, fire could very easily come up the hill quickly. And so I have an area on my slope in front of my house that's where my fruit trees are that I irrigate the area underneath them. And so it's pretty green in that area. And so in a sense, that's my first line of defense if fire did come up.

Farmer Fred:

[36:02] How wide is that area?

Kevin Marini:

[36:05] Oh, probably about 25 feet and probably, yeah, 30 yards. I mean, it's a pretty big area. And I did that on purpose, of course, to really make sure I have a fire barrier there or at least a buffer.

Farmer Fred:

[36:18] When we lived in the country, and even though it was pasture land, not too far in the distance, a quarter mile away, was a square mile of eucalyptus trees that were put in around 1910 or so. It was a get-rich-quick scheme by someone thinking that it would make for great furniture that's very malleable. And it turned out this particular eucalyptus variety was rather brittle. So the trees just remained. So we were always looking at that, knowing that the delta breezes blew in towards us from that grove. So we were always thinking about, okay, how do we intercept the embers? And one of the plans was to put sprinklers on the roof. Okay, what are you going to do? How are you going to run it? If the electricity goes out, because that's what usually happens first in the country. So we were on a well. And  the first thing I did was make it a triple throw switch out at the pump  where I could switch off the electricity to the pump and then pull it down so I could hook up a generator to it. So at least we'd have water going, And at least keep things irrigated, or turn on the sprinklers. Does a swimming pool play a part in this?

Kevin Marini:

[37:32] Sure. I think ponds up in Placer County here, we have a lot of ponds on people's properties and pools. And that does play into it because the ability to pump out of a swimming pool and potentially put a small fire out would be huge if needed. And I know this sounds a little dreary, but in worst case scenario, if you're inundated by fire, at least having a pool to jump into may save your life. There's been some real kind of horror stories I know about that where people haven't survived, but there's been plenty of stories where people have too.

So I know for a fact that insurance companies look at that and give you a little nod if you have some sort of a body of water nearby. So, yeah, I think that helps for sure. And I think, you know, CAL FIRE has, I specifically talked to representatives from CAL FIRE about this. They don't really encourage this whole roof sprinkler thing, which in a way I could see people saying, why not? Why wouldn't you want a roof sprinkler system if, you know, you live in a high severity fire zone? And like you say, there's an electricity issue if you're on a well. And if you're actually on city water, they don't really want people evacuating but leaving the water on, potentially messing with their ability to get water and have the pressure they need to put out the fires. So I think that in general, there may be some situations like you talked about, you have a generator situation where you could have some roof sprinklers, but it's not really highly encouraged over being prepared as far as defensible space and having that sort of just passive resilience set up.

Farmer Fred:

[39:16] I have some pretty smart friends who are in the nursery business. And some of my friends own a wholesale nursery and they grow citrus trees. But where they're growing their citrus trees is in this canyon that is prone to wildfires on either side. They've escaped it. So far, one of the reasons they've escaped it is they had access to a creek and they cleared off enough of an area and put in a new road to their property that was wide enough for two fire engines to pass each other. And down at the base where the creek was, they installed equipment so the fire trucks could resupply their trucks with water.

Kevin Marini:

[39:58] Wow. Wow. How interesting.

Farmer Fred:

[40:00] And so that's one of the first places the fire department will defend is where they get their source of water. 

Kevin Marini:

[40:07] Yeah. And I'm actually glad you brought that up because it reminded me of something I do not want to forget to mention, which is the first thing I always bring

 up if I'm giving any type of a presentation to a Firewise community or a community group. And that is ingress-egress, right? The way in and out of your property, of your neighborhood. Oh, this, we've seen some really disturbing images during the Camp Fire, of people trying to get out and flames all around. So in many places, especially in more rural areas, my area, my neighborhood, I have one way out. You know,  if the fire's coming up that road, I'm going out on foot in a different direction. Wow.  So I think this is super important for people to be thinking about. And I would say that even if you're in a suburban neighborhood, we saw what happened during the Tubbs fire that you that you had mentioned earlier on. And, you know, it's just there's so many people in vehicles trying to get out of an area. And there's so many fire personnel trying to get in. Right. So even in a situation like a suburban neighborhood, you can really run into some traffic jam situations.

So have alternate routes. Have different ways that you can exit depending on what direction that fire is coming and what direction you're getting from fire personnel. I know I have a very long, narrow driveway up to my house. And I'll never forget the first time I had the fire department come up here. It was actually due to  my mother-in-law, who had a health emergency. She turned out to be fine. But they sure gave me a mouthful about my driveway and the branches that were rubbing up against their beautiful fire truck on the way up.  And they basically told me, we will not drive up here and defend your home in a fire. We will not. There's no turnaround up here. You have branches that are too close to the driveway. All of that needs to be cut back. And you need to have a very easy turnaround for a fire engine. And so we did that. We did that work. And so that's another thing. It's not just that you're in and out of an area. It's making sure that fire engines can get in and out of your area where you live.

DAVE WILSON NURSERY

Farmer Fred:

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DEFENSIBLE SPACE LANDSCAPING TIPS, PT. 3

Farmer Fred:

[43:41] Let's get back to our conversation with Kevin Marini, University of California Defensible Space Consultant. He has tips for protecting your home from wildfires by adjusting your landscaping. And here's one nifty piece of landscaping that does look nice from a distance, but actually could be a death trap.

Farmer Fred:

[44:02] You brought up another good point with that, too. And so many people who live in suburban and rural areas will do this, and that is to line their driveway on both sides with trees. That's a death trap. And especially when they want quick-growing trees. So, it's usually some sort of junk tree, like a Lombardy poplar or something like that, a tree species that has a lot of deadwood, a lot of litter. And if you've got these 30, 40, 50 foot giants on either side of your driveway, and they catch fire, who's going to drive through a fire tunnel to help you out? Nobody.

Kevin Marini:

[44:35] Exactly. Exactly. And I see this up in the foothills a lot with coast redwoods. I love redwood trees, don't get me wrong, but putting coast redwoods up here in this climate is a little, I wouldn't say it's the best choice. Let's just put it that way. But one thing that I see people do, of course, is plant these coast redwoods way too close together. When they're young, they're going for this screen, right, or this look, like you say, this kind of look up a driveway or something. And the reality is as they grow, you know, they just basically intertwine. And so you have these huge swaths of vegetation that if that catches fire in there, I mean, there's no way, like you say, you're driving through that without some damage.

Farmer Fred:

[45:23] Have, like you say, have an alternate route out, at least.

Kevin Marini:

[45:26] At least. At least. It was a way that I convinced my wife that we needed a quad (an all-terrain vehicle). You know, we really needed a quad for fire. That's why we needed it, right? Not for me. No, no. You know, to be safe. So in an emergency, I could put you guys on a quad and get you out of it. Right. It worked.

Farmer Fred:

[45:45] Good thing you weren't an amateur pilot.

Kevin Marini:

[45:48] Yeah. Yeah. So I think, you know, going over these defensible space zones is important and it's important for people to do the maintenance in their yards and to not get so overwhelmed by the situation because this is never going to end. And  this might sound a little negative, but it's not meant to. But I tell people, look, you're never going to be done with defensible space landscape work. Because as gardeners know, you don't weed an area and then say, I'm done. I'm never going to have to weed that area again. We know things grow, right? And seeds come in and branches grow.  And so this type of work, yes, there may be a lot of work up front to get your yard to a point where it's looking pretty good defensible space-wise. But we also have to remember that this is just something that you do all the time. Every year, there's a little bit more work, a little bit more cleaning up. And a lot of folks in the foothills would love to throw a lot of money at a problem and see it go away. But unfortunately, that's not the case in most environments.

Farmer Fred:

[47:04] Cal Fire also points out that fire resistant ground covers are also an acceptable choice for that area, five to 30 feet. And to avoid planting broadleaf evergreens like holly and coyote bush, conifers like pines, juniper, cedars and firs, avoid those. And also, and this may come as a surprise, avoid planting palm trees because they are highly flammable.

Kevin Marini:

[47:28] Yeah, yeah. And so this is a good kind of counterpoint to make to the firewise plant statement I made earlier. So I was saying it's less about the species. It's more about its maintenance and how you organize the plants and landscape. However, if there is good data that we have, it is on flammable plants. So, there's no research that says, oh, this pallet of plants in the case of embers coming in is going to be completely safe, right? But what we do know is we know flammable plants to avoid in those defensible space zones. So, you mentioned a few. I mentioned juniper earlier. Believe it or not, bamboo is usually considered a part of that because there's

so much accumulation of dead foliage, right? Right. And so a lot of conifer type plants, whether they're small or large, are considered very flammable and not the best choices in defensible space zones. So I think you bring up a good important point that it may not be that we swap out all of the plants in our landscape with so-called firewise plants, but that doesn't mean that we don't identify very flammable plants and rid ourselves of those in the defensible space zones.

Farmer Fred:

[48:47] Yeah, two other pieces of flammability that people sometimes forget about that they might have near their house are propane tanks and the woodpile. How many people have woodpiles on their porch?

Kevin Marini:

[48:57] Isn't that the truth. That's a tough one,  because we kind of live in a situation in California where there's no ‘fire seasons’ anymore; just year-round basically. Of course when we have  a bunch of nice soaking rainstorms it goes away for a little bit, but there definitely can be times during the winter where we have stretches of three or four weeks without a drop of rain and everything gets bone dry. And you have all this wood up on your porch and suddenly now you have to consider moving that, right? Because everything else was dried out so i agree with you that that there's things all around the home. Now the propane tank thing is interesting. I was at a fire network meeting and I heard a Cal Fire gentleman say he puts his barbecue with the the propane tank, he wheels it into his garage, and when he wants to use it, he wheels it out of his garage and uses it, and then puts it back in the garage.

And I kind of thought, hmm, I wonder, what's the take-home point there? Well, the take-home point is, if you have it outside and you have other flammable material around and that catches fire, then you risk that propane tank exploding and creating a most likely a big house fire, right? And so I thought that was an interesting point of just something so simple like that. Wheel it in your garage, and if you're going to use it, wheel it out. Up here, a lot of people have large propane tanks. It's recommended to keep those at least 30 feet away from your home, but so many people have them very close to their home. Again, it's important to make sure there's no dry vegetation around those propane tanks. Some people put wooden structures around them to hide them. You can't do that because, obviously, that can catch fire and blow up the propane tank. And I think another thing to think about is firefighter safety. So if you have an area on your property where a fire engine could set up and defend your house, well, hopefully that's not five feet away from a propane tank, right?

Farmer Fred:

[51:03] You know, thinking about all this makes me, if I lived in the country again, I'd want a separate shed so I can store all the flammable materials, be it gas or paint or a propane tank, into a shed with the other flammable materials so that my property that I might value, like my bicycles, in the garage, wouldn't get harmed.

Kevin Marini:

[51:21] Yeah, yeah, I know. And out here in the country, as extreme as thinking like that may be, it does make sense when you see the way that these fires in high wind situations, how quickly they move and how the volume of embers that come in, right? And so having everything that is flammable or that could explode, over there, I think, would make you sleep a little bit better.

Farmer Fred:

[51:55] Well, it's that time of year here in California. We're sure mid to late fall, where it can get hot and dry and the conditions are just right for disaster. So take care of your own property. And remember, there's no such thing as a fireproof plant, but there can be fire resistant plants, especially if you keep them well irrigated.

Kevin Marini:

[52:18] Yes.  And so that's a really good point that they have found that the moisture within leaves, within foliage can really impact whether that plant is going to ignite or not or burn or not. So, you know, the idea of holding back water with plants around your home is probably not a good idea. If anything, you want those plants to be always well hydrated during fire seasons.

Farmer Fred:

[52:46] It sounds like you can't have anything from zero to five feet, five to 30 feet, just succulents, and beyond 30 feet, just little trees.

Kevin Marini:

[52:55] You know, I have a lot of people who say, I have invested so much time, so much money, so much effort in creating this landscape. I'm not going to allow it to become all rock with a few succulents somewhere. And my response is usually it doesn't have to be that way. Because  look at some models of defensible space. There's a great Marin County program,  an amazing fire program, doing homeowner education and outreach. And they have just an amazing website, Fire Safe Marin. Of course, they have a special tax that funds all this to makeit possible.

But that's a great resource for folks because they have good pictures of what nice looking landscapes that are showy can look like, but also can be good defensible space landscapes. And so I think once you kind of see those examples, you realize it doesn't have to be so dreary. But I hear your point, though, that we do have to rethink this love we have for lush, very textured landscapes that are almost jungle-like. It's just not going to work, especially because things are getting hotter and drier, right? So the other factor here is we have the climate changing, and all you have to do is talk to firefighters, and they will tell you fuels dry out a lot sooner, and they are bone dry a lot longer. And so the fire season window of time has increased and is increasing.

Farmer Fred:

[54:31] Yeah, keep rakes and loppers handy all over the yard so you'll be inclined to pick them up and use them. I mentioned earlier in this program that it's quite possible that on your insurance bill, especially if you're a California resident, you might see a new box that lists your propensity for being in a wildland urban interface problem area. And basically, I guess the worse the number, the higher your insurance rates. So the lack of insurance, I'm still amazed at the number of people who think they don't need insurance because their house is paid for.

Kevin Marini:

[55:06] Yeah, the insurance conundrum is crazy right now. And first of all, these fire zones are being kind of remapped. And this is going to be an ongoing process as things change. And so I know that CAL FIRE is working with UC fire scientists and other folks on trying to figure out the best way to map these fire zones. And that definitely plays into insurance coverage, no doubt. The one thing I have found, okay, and I have spoken to a lot of people over the last few years, especially in the Foothill area of Placer and Nevada counties, and I really have found that the insurance situation is variable. There does not seem to be this total line in the sand or overarching rule applied everywhere, even in high severity fire zones like I live in. My insurance was recently renewed. And the three things we had to do had nothing to do with vegetation, for example. You hear the entity that I have insurance with that they're canceling by zip code or there's so much misinformation out there when it comes to insurance. And so, the one thing for people to know for sure is that because this zero to five ember ignition zone is currently not law, the entities that are really enforcing it are your insurance agencies and your HOAs, your homeowner associations.

For example, I gave a talk up at Tahoe Donner out of Truckee and it's a big development and they have a very active HOA, especially in regards to fire. And so, they have a zero to 10-foot zone around homes that's required to be completely devoid of flammable material. So, that HOA has taken the state law and upped it, doubled it, right? Or what might be, what will be state law, and doubled it. And so many people are facing this Ember Ignition Zone through their HOA interface or through an interface with an insurance agency that says, unless that's clear, we can't insure you. In fact, there are new certifications that some insurance companies are using today. Where they have people come out, they send people out and certify that your house is a defensible space compliant landscape where that zero to five is clear. And that's how you get insurance. There are new companies that have popped up that will come and spray retardant around your home. They do it annually or biannually, and that can lead to being insured or getting discounts on insurance, becoming part of a firewise community can offer discounts and other benefits for insurance.

So it's not one size fits all. It's variable, and it's kind of all over the place. So I understand people's frustration with that situation. But also, let's understand that we find ourselves in a situation because of these catastrophic wildfires that make insuring areas of California, a little risky, right? Yeah.

Farmer Fred:

[58:23] How wide does a driveway have to be for two fire engines to pass each other?

Kevin Marini:

[58:28] That's a good question. I don't want to give a wrong answer here. So there's probably like a exact answer. And I just I don't want to say anything and give the wrong answer. So I'm going to say, I don't know exactly.

Farmer Fred:

[58:42] Yeah, I think that'd be safe. Maybe 30 feet. I don't know.

Kevin Marini:

[58:47] Yeah. I mean, most private roads out here in the foothills, you know, are barely 20 feet wide. My road leading out  is very narrow in spots. So I know for a fact that  you couldn't have two fire engines pass, for example, on my little private road here. I think the biggest thing that I've heard from fire personnel is the ability to turn around, right? So if they have to back down a large driveway, they aren't coming up. And it's important to also recognize that the whole original meaning behind the term defensible space was really not about your home or landscape. It was more about having a space where firefighters can defend your home. The original kind of term was like, hey, make sure you have defensible space, meaning make sure you have a way for a big fire engine to come up to hang out there and actually defend your home. So I think that is lost on a lot of folks. I don't think a lot of people think of that when thinking of defensible space.

Farmer Fred:

[59:50] Well, there's your five to 30 foot zone. You have a driveway going all the way around the house and back out.

Kevin Marini:

[59:55] There you go. There you go. And I've seen that. You know, I've seen people in  Loomis and Newcastle, you know, have a driveway that comes up and they literally add a huge turn, you know, a huge circle to their driveway. So a fire engine could completely circle their property and defend their property from all different aspects.

Farmer Fred:

[1:00:15] Right. It was either the fire department that complained or the UPS driver.

Kevin Marini:

[1:00:19] Well, good point. Yeah. Yeah. UPS trucks are pretty tall, too. They they definitely have given me an earful about those tree branches as well.

Farmer Fred:

[1:00:28] All right. For more information about defensible space, we're going to have all sorts of links in today's show notes that go throughout many states to discuss safety in wildfires and fire resistant landscaping. So be sure to check the show notes for all these links for more information. Is there a good link for people to get to for lists of recommended plants? I realize all gardening is local and every state or wildfire area is going to have a different list of plants. But is there some starting points?

Kevin Marini:

[1:01:00] Well, I think there's two that I'll mention. So, number one, I mentioned FireSafe Marin, that website. Even though I recognize that not all those plants will work in all zones in California, at least they give you a good representation of plants that have some fire resistance. Okay, so that's a good website. And they have pictures, having just plant lists that are just all text, just don't do it for a lot of people, right?

Farmer Fred:

[1:01:25] Not in the 21st century.

Kevin Marini:

[1:01:27] Yeah, you need those pictures. And I'll also plug the California Native Plant Society. So, you know, it is pretty well known that native plants generally, not all of them, of course, but they generally have co-evolved with fire, especially here in California. And so many of them offer some characteristics that lend themselves to fire resilience. So the California Native Plant Society also has some lists of native plants to at least consider if you're swapping out plants. Those two, I think, would be the best. And like I said, otherwise, the most important thing is looking at your landscape and looking at how you can create space and how you can maintain certain plants for fire safety. And so Master Gardener programs are great resources for folks. They can call up the Master Gardener hotline or there are many counties that can shoot a question over email, and they can get some pruning advice. They can get some plant advice. And so I would say I gave you three resources. Those would be where I would go to first.

Farmer Fred:

[1:02:37] I think those are great resources, and I'm glad the University of California has spent more money over the last 10 years on hiring more people like you to do your job of talking about defensible space.

Kevin Marini:

[1:02:48] Yes, absolutely. They've invested heavily. We have a UCANR, University of California Ag and Natural Resources, UCANR fire team, which is spread up and down the state. We have a local fire scientist expert in our office in Placer County. Her name is Katie Lowe. And so she's doing research right now out in the forest, believe it or not, on using goats for vegetation management out in forested areas, for example. And she does a lot of home hardening education and outreach locally. I had mentioned that my focus was more on plants and landscape; well, we do have experts in the home hardening realm as well.

Farmer Fred:

[1:03:30] All right. Kevin Marini, he's with the UC Cooperative Extension. He's Master Gardener advisor, he's a certified arborist, and a UC educator on defensible space. Kevin, thanks for your time, thanks for all the great tips.

Kevin Marini:

[1:03:42] No problem. I really enjoyed it. Great talking with you again.

WANT TO LEAVE US A GARDEN QUESTION?

Farmer Fred:

[1:03:54] Want to leave us a garden question? You'll find a link at GardenBasics.net. Also, when you click on any episode at GardenBasics.net, you're going to find a link to SpeakPipe. You'll find it in the show notes. And when you bring up SpeakPipe on your computer or smartphone, you can leave us an audio question without making a phone call. Or you can go to SpeakPipe directly. That's SpeakPipe.com slash GardenBasics. You want to call or text us? We have that number posted at GardenBasics.net. It's 916-292-8964. 916-292-8964. Email? Sure, we like email. Send it along with your pictures to Fred at FarmerFred.com. Or again, go to GardenBasics.net and get that link. And if you send us a question, be sure to tell us where you're gardening, because all gardening is local. Find it all at GardenBasics.net. 

Garden Basics with Farmer Fred comes out every Friday. It's brought to you by SmartPots and Dave Wilson Nursery. Garden Basics, it's available wherever podcasts are handed out. For more information about the podcast, as well as an accurate transcript, visit our website, GardenBasics.net. And there, you can find out about our newsletter, Beyond the Garden Basics. And thank you so much for listening and your support.