Monday, February 25. 2008
Here is an email Greg Rubin sent to the Encinitas fire department on redwood mulch and its performance in the Cedar fire. His accompanying photos are at the end of this entry. (Published with his permission.)
Sunday, February 24. 2008
wildbird in Wildfire
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Greg Rubin, a San Diego area landscape designer and contractor, helps people to design their yards so as to be beautiful, use little water, and survive wildfires. Here is a letter that he sent to the California Native Plant Society's San Diego chapter last week. (Used here with his permission.)
And he sent along some photos to corroborate his statements. Click on any link to see a full-sized image. Again, his words:
Here is another photo he sent later:
Tuesday, January 22. 2008
Rick Halsey, Director and Fire Ecologist, California Chaparral Institute has conducted a very sensible and level-headed interview on chaparral and wildfire on SanDiego radio station 94.9. You can listen to it by clicking here. I don't know how long it will be in the archives so listen now.
Wednesday, November 21. 2007
My previous postings were about things that can be studied and understood: how wildfires start, how they progress, how they ignite homes, etc. Today posting is much more subjective as it deals with human beings (not very rational in the best of circumstances) and politics (never, ever rational or even close to it.) So bear with me if I step on your toes and you don't agree with me. This is all opinion, even when stated by so-called experts, and we all have a right to our opinions. Mine are also open to change, though I need to hear reason, not emotion.
Let's imagine (fantasize, really) that powerlines are placed underground, the highly flammable non-native weeds (the tinder to start the blazes) is eradicated, and the undeveloped areas of southern California are returned to healthy, fire-resistant chaparral systems. Imagine that we all take steps to make our homes more fire-resistant. What else can be done?
No matter what protective and defensive measures are taken there will still be risk of fire and communities must plan to survive them. We have a terrible problem of sprawl in southern California and I think it's time to tighten it up a bit. Look at this photo. The red dots are houses which burned in the Witch fire. The fire came over Bernardo Mountain (on the right in the photo) and rammed into the neighborhood like a freight train. I've been in one of these houses before it burned and have looked at a number of them from the road and they were designed to burn. Remember, the embers start most of these house fires and these houses were blasted by a lot of embers. They were also subject to intense radiant heat. But even if made fireproof, some of them still might have burned. That fire was incredibly powerful.
(By the way, professionals call that area along the eastern and southeastern edge of our neighborhood the "urban/wildland interface". That's nice and if you want to use the term, go for it. But we need to get away from the mentality that only professionals should deal with these things and the rest of us need only focus on our jobs and football games and sun tans. It affects us all, so pay attention and think and learn ... or prepare to lose your home next.)
But notice that the red dots are just clustered along the eastern and southeastern edge of the neighborhood. The fire just seemed to peter out after it struck the neighborhood like a hurricane does when it comes ashore from the ocean. Why didn't the fire keep going and burn the whole neighborhood? Two reasons: irrigated landscaping and firefighters. Not all of the land to the left of the red dots is irrigated, but a lot of it is, at least part of the time. And much of the landscaping around the houses that burned did not burn. This really weakens the fire and gives firefighters the chance to stop it. A neighbor was watching the fire from the top of a hill as it came down the mountain and crashed into the side of the neighborhood and he said that there were firemen and helicopters all over the place. It is very sad that the ones on the edge burned, but firefighters may well have died if they tried to defend them, they were just too exposed and built to burn. They fought furiously to save the rest and succeeded.
What do we learn from that? Well, remember the fire triangle? If you can remove fuel, heat, or oxygen from a fire you will kill it. If we can reduce or eliminate the number of houses that catch fire we will remove a lot of fuel from the fire. If we irrigate the landscaping immediately surrounding our homes, we remove heat from the fire (because it requires a lot of heat to dry the vegetation before it will burn.)
Now think about this: ours is a cohesive neighborhood, but what about outlying homes that are more widely scattered? Every one of them is on an edge. They must all be able to bear the full force of the fire.
So what can a community do about it? We cannot irrigate the millions of acres of wildlands in the county and it would be a very bad idea to do so if we could (it would just create a lot more fuel.) In a cohesive neighborhood or city, attention must be paid to the homes which are going to be hit by the full force of the fire - typically those on the east or south side of the community and facing open, unirrigated wildlands. These homes and yards must be designed to absorb the impact of the advancing fire and keep it from going further. That means that the homeowners or contractors who build these homes will fall under more restrictive regulations than the rest of the neighborhood. They will whine about it being unfair and we must have the resolve to hold them to those higher standards. It's the price they must pay for putting their houses in harm's way. If they are going to put their homes upwind of everyone else's, they must accept the responsibility not to allow the fire to pass their yards. If the unprepared houses in the photo can do it, think how well it would work if those houses and yards had be designed to stop the fires.
That doesn't let everyone else off the hook. Burning embers can still blow past those buffer houses on the edge and ignite houses further into the neighborhood. Because we know that many people will not take the steps necessary I do think it is the responsibility of communities to force homeowners to do so. I know, a lot of people don't like what sounds like Big Brother meddling, but it's not just your issue if your house catches fire, it can generate
Communities also need to bolster their fire protection. San Diego county's fire departments are grossly underfunded in comparison to other areas with similar fire danger. There seems to be some sort of almost religious opposition to taxes of any kind. Well that's foolishness. We clearly need more firefighters, we need more of them to be READY to roll (not just at home "on-call" because of budget constraints) and we need more aircraft. Bulldozers just mess up the land and the fire jumps right over the fire breaks, but aircraft can really fight these fires. Look at this baby. It can drop 12,000 gallons of water or fire retardant in one swoop. Our usual C-130s (nice as they are!) can only carry 3000 gallons. We need a fleet of those big guys! But we don't even have one. Why not? Or look at this one. Sure, it's Russian, but who cares? They're not the enemy anymore. In fact, they want to be even more friendly and sell or lease us these incredible planes. Scroll down in the above link to the 11-76P variant - the firefighting plane - and look at it. It will carry 13,000 gallons and can reload in 15 minutes. Socko! I know it's hard to fight a fire with fixed wing aircraft in high winds, but who needs to attack the fire directly? With some of these planes you could soak an area to the east and southeast of a community in a few minutes and keep doing it until the fire hits the wet spot - and fizzles, or at least weakens so the firefighters on the ground can attack it. I know it won't work perfectly - nothing ever does - but it would really help as the fire would not have quite as much punch when it hit the community.
If communities were more cohesive, then there would be less of them exposed on the edges. Then it might even be possible to built a ring of huge sprinklers along the high risk areas to be turned on at the approach of a fire. That might not be enough to totally stop a fire, but wet wood doesn't burn and it takes energy away from the fire to dry it out. If it could just weaken the oncoming fire front that would give the firefighters a chance to defend more homes around the edge. But with our sprawling mess of unplanned development such things are just day dreams.
One last thing to remember about communities: they are not made of bureaucrats, they are made of citizens. We need to all get involved in protecting ourselves from fire or we will never win.
Tuesday, November 20. 2007
wildbird in Wildfire
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In my last entry I listed the three causes of structural ignition by wildfires: direct contact by the flames, radiation, and embers. Now what to do about them?
The flames in a wildfire can travel up to 200 feet when driven by the extremely powerful Santa Ana winds, but in most cases they are less. If you've ever watched a fire you know that the flames aren't steady like a blowtorch but move around a lot. So if your house is in the direct path of the blaze it may be brushed by those 200 foot long flames, but only briefly. As the fire gets closer than 200 feet the flames will be in more constant contact with your house and that's really more risky. The fire department suggests that vegetation be "managed" within 100 feet of a structure. This does not mean cleared, it just means kept trimmed up, clear of dead material and weeds. By doing this, you will greatly reduce the fuel available to the fire within the real danger zone to your house. Without so much fuel, the fire advancing on your house will not be able to sustain constant flames against your structure. The fire will burn past quickly, leaving a well-built and prepared house intact. Any vegetation within this area should not receive year-round irrigation because that just causes it to generate more fuel, but should be irrigated lightly during fire season. Native plants are very good in this area because they do not burn as easily when dry as non-natives and because it takes very little water to "green them up" and make them very fire resistant.
Radiation, as I said, is reduced by distance to the blaze. The fire department recommends a 30 to 50 foot zone that is clear of any flammable materials. Any landscaping witin this zone can be irrigated year-round, but should certainly be well irrigated in the fire season - especially if it includes non-native plants which burn very easily when dry. But vegetation is not the only flammable material you will find within 30-50 feet of a house. You should not have wooden fences within this zone. If you build a garden shed, do not think "it's only a shed, so I don't care if it burns" because it could give off enough radiation to start your house on fire. If a neighboring house is within 30-50 feet it is a radiation hazard; if it should burn it could also ignite your house. So be your brother's keeper and talk to your neighbors about making their house fire-safe, too!
Embers are the biggest danger to most houses. I looked at some aerial views of Rancho Bernardo after the fires and noticed that many of the houses that burned were not on the edges of the canyons, but right out in the middle of the neighborhood. They were surrounded by dozens - sometimes hundreds - of unburned houses and landscaping. These houses could only have ignited by embers.
Embers are flaming pieces of wood or woody plant material that are blown through the air ahead of the fire. They will rain down upon you if you are sheltered by the wind and they will hammer into the side of your house if you are exposed to it during the fire. If they come to rest against something flammable, they could ignite it. But not necessarily. Remember my earlier posting on how fires start? Those embers must be able to heat the material that they are in contact with enough so it will ignite. If an ember comes into contact with a piece of 2x6 decking material it probably will not ignite it. A rain of embers, some as large as your finger, fell on our house during the Witch fire in 2007 and did not ignite anything. But if a large ember comes into contact with some good tinder, then it could ignite a fire. Where can it find tinder? If your gutters are full of dry leaves or pine needles, that's some very good tinder. One of the most common ways for an ember to find tinder is if it gets blown into your attic vents and lands upon the tar paper facing of your ceiling insulation. That is also some very good tinder - some of the best! Also, if a lot of embers get forced into a corner, they form a little "bed of coals" - a self-sustaining fire. The wind will fan them into a very hot furnace and even if they are in contact with a large piece of wood they can cause it to ignite. This is why decks which overhang a slope are so dangerous. If you look underneath your deck you will see a LOT of little wooden corners for these embers to accumulate in. It only takes one little pile of them to ignite your deck and that will, in turn, ignite your house.
To protect yourself against embers you must make sure that they cannot contact anything which will act as tinder and that they cannot pile up against any exposed wood. That means either screening your attic vents with very fine mesh screen or eliminating them altogether (not a good idea for other structural reasons.) It means keeping your gutters clean. (And if the gutters are filling up with pine needles or eucalyptus leaves, cut those highly flammable trees down!) It means covering any exposed wood with stucco or cement board. Decks can be skirted or totally enclosed underneath, eaves can be enclosed with stucco or cement board.
One very difficult form of ember to protect your house from is flaming palm fronds. Our Fire Marshal here in Escondido once told us that firemen call them "Roman candles". An ember the size of your finger will most likely just bounce off the side of your house and fall on the ground. But when a palm tree burns the fronds - dead and green, both, come off of it whole and often flaming. If the wind is blowing 60 MPH or more, that means a 10 pound flaming palm frond will be flying through the air at 60 MPH. If that strikes your window, it will go right on through. There's not much you can do to prepare the structure from this, you must eliminate the threat at its source. Look around your house. Any palm trees upwind of you (generally, east of you during a fire) are a very direct threat to your house. If they are on your property, you should cut them down. If they are on your neighbor's property, you should ask them to cut them down. If you have palms on your property which are upwind of your neighbors you should cut them down. I know, the palms look so cool here in our mediterranean looking county, but they are dangerous and do not belong here. They are not native. (There are native palms, but they are small and squat and nobody seems to plant them.) There is really no good reason to keep them and a lot of very good reasons to get rid of them.
Tuesday, November 20. 2007
wildbird in Wildfire
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How do houses catch fire in a wildfire? There are three basic ways.
One is by direct contact with flames. If there is dry vegetation (native or non-native) near your house - especially on the east side - or if you are on a canyon rim overlooking wildlands, then the flames may actually lick against the side of your house and heat it enough to ignite it. This is actually pretty rare. Remember my previous entry telling about how to start a fire? If your house is reasonably well built, and does not have cedar on the exterior, it will take a sustained flame to get it going. Since these fires usually move through very quickly, the flames will not be sustained on any one piece of wood for a long time.
The second way that houses catch fire in a wildfire is through radiation. Burning material (vegetation or a neighbor's burning house) gives off a lot of infrared radiation. This heats up surfaces that it touches and if they get above the flash point, they burn. Infrared can go right through your windows and ignite the blinds inside, or wallpaper or the newpapers piled on your end table, carpeting, etc. Anything that faces towards the blaze will receive infrared radiation and could potentially catch fire. Stucco and tile are resistent to infrared heating (they have a lot of thermal mass and so just absorb it and heat up very slowly) and infrared-reflecting windows are available to reduce (not eliminate) the risk of igniting curtains and such. The thing with infrared radiation is that it diminishes with distance. The farther you are from the fire, the less intense the infrared radiation.
The third way that houses catch fire in a wildfire is by contact with burning embers. Of the 20 houses in our neighborhood that burned, most of them are still surrounded by green, living landscaping. These houses did not appear to have burned through direct contact with flames - where would the flames have come from? And they did not appear to have been ignited by infrared radiation - all that greenery would have blocked most of it and would have been all wilted. I think these houses - most or all of them - were ignited by burning embers which travelled through the air and found vulnerabilities in the structures which they were able to exploit.
I have read that over 90% of the houses which catch fire do so because of embers. That means it is very important to understand embers and how they initiate a blaze. I will address that in my next entry.
Tuesday, November 20. 2007
I think most people in our modern world have never actually started a fire. Even hunters and campers and other outdoor types usually use stoves rather than fires. In fact I think open fires are illegal in most parks and forests. When I was young I went camping a LOT and we only used open fires for our cooking, not stoves. I have also lived in houses heating primarily or solely by woodstove heat for most of my life. So I know a lot about how fires start and they must follow a progression or you won't get a fire going.
Any understanding of fire must start with the basic requirements for a blaze, known as the "fire triangle": fuel, heat, oxygen". It's simple. Hot oxygen doesn't burn with no fuel present. Cold wood doesn't burn even in pure oxygen. Hot wood doesn't burn without oxygen. You must have all three. When you start a fire, you must heat the fuel to a point where it starts giving off gases which will burn - the "flash point". To keep a fire going, the fuel must generate enough heat to heat up more fuel to the flash point.If you want to start a fire (a legal one, not a wildfire!) you must start with very small, fine material called "tinder". We do this because it is extremely hard to heat a large piece of wood enough to give off enough flammable gases to burn and keep burning. Often a wad of dried grass can be used as tinder if it is truly dry. Or you can cut shavings from pieces of wood, but when you do this you always select types of wood such as cedar or pine that are known to burn well. Above the tinder you carefully arrange small pieces of wood called "kindling". Again, you always select highly flammable types of wood for the kindling because otherwise the fire may not start. Those two steps often involve a lot of blowing on the fire (adding more oxygen) to help it grow. After the kindling gets going you can put your fuel wood on top. At first you want to use dry and preferably highly flammable fuel woods, but after you have a bed of coals to keep the fire going you can burn almost anything. Notice that one must be careful in the selection of material to use as tinder and kindling. It really does matter because most materials make poor tinder or kindling. It's just too hard to get them started and keep them started.
That progression is very similar to how a wildfire gets started. A few sparks or a cigarette butt cannot ignite the main fuel, it must start with something that can actually be ignited by a spark. And even then, a spark will often burn out in tinder unless you (or the wind) blow on it. Look at this webpage that illustrates the amount of time (how much heat) it takes to get various plants to burn. And notice that many will not burn at all, even when blasted with a propane torch.
Looking at those burn times, it seems most likely that the tinder is going to be the non-native grasses, mustard, star thistle and melilotus because those things start burning almost immediately - before the original spark goes out. Once those things get started, it will transfer the flame to the smaller branches of the very dry native and non-native plants along the road or power line, and if the wind keeps blowing that will become a larger conflagration. Without the wind the fires will probably fizzle out when they get away from the non-native "tinder species" and into the pure chaparral. Or if they don't go out they will burn very slowly because most of the native chaparral species take a long time to get started. With the wind blowing, anything dry (native, non-native, and structures) will burn once the fire starts.
I think that eliminating these non-native "tinder species" will almost eliminate the fire hazard. Not totally, but life is all a probability game, anyway. It's a really big job. They are everywhere we have been: along roads, powerlines, homesteads, and even trails. And they spread inland from there. We all need to do our part. I cannot fathom the effort to rid all of San Diego county of non-natives, but I can imagine doing it on my own property, because we are doing just that - and it is very possible. If two old timers like my wife and I can do it, so can almost everyone. As for the infestation along public roads, trails, and powerlines, it could cost millions...but the fires of 2007 alone cost well over a billion. Sounds like a bargain to me.
And I think planting and tending the fire-resistant native chaparral species everywhere we possibly can is the only way to keep the non-native weeds out once we have irradicated them, because they form a shady "umbrella" keeping the sun off of the lower growing weeds.
Sunday, November 18. 2007
I was up at the edge of the fire above Lake Hodges the other day and it was quite a sight. I expected to see lots of charcoal and ash and half burnt plants and such. But nope, there was nothing but bare dirt and rocks except for the perimeter. Quite a shock. The scope of the loss is immense. This was mostly healthy chaparral. I could look down and see where we sighted California gnatcatchers in the past. Nothing is there now. The little clearing where I found a bunch of mushrooms one winter is just sterile dirt. Amazing. And to think that this was all preventable.
Back in 1980 I was preparing to build a house in the Oregon woods. It would be about 1/4 mile from the nearest road, though probably only 1/10 mile from a power line on a neighbor's property. The power company told me that they would put a line in to my house at no cost if it were hanging on poles, but that if I wanted to bury it I would have to pay to have the ditch dug. A five foot deep, 1/4 mile ditch was quite expensive for me at that time. I was working two jobs to make ends meet and was going to have to do most of the building myself, so you can see that I was on a very tight budget. But I took the intelligent step of paying to bury the lines to my house and I never regretted it. My lines never came down in an ice or wind storm, though many surrounding me did.
That was almost 30 years ago and burying lines was not a new thing even then. Fast forward to 2007. Three of the major fires in southern California this fall - including the Witch fire that burned the San Dieguito River Park - were started by falling power lines. Hundreds of thousands of acres, billions of dollars, millions more in lost productivity, and quite a few human lives were lost in these fires. Will the power companies be held liable? Of course not. But why not? They were negligent. Regardless what various laws they may or may not have complied with, the technology to prevent these fires has existed for decades and they know of the fire danger when lines fall and they did nothing to prevent it.
I, for one, want to see the power companies who were at fault in causing these fires held accountable. The power companies have claimed that they were obeying the laws in the creation and maintenance of these power lines, but I consider that irrelevant. If I have two alternatives to a problem, both legal, one high risk and one low risk, and I choose the high risk alternative and someone is harmed guess what? I am liable. And so should they be. They knew that downed power lines start wildfires because it has happened many times in the past.
And let's talk a bit about how these fires actually get their start. It is convenient for people to mention "brush" as if it is all the same (and as if they know what they are talking about.) In fact, there are many kinds of native "brush" (many mixes of species making many types of chaparral and scrub) and then there is the mixing of native and non-native. While most of the unbroken chaparral of southern California was probably mostly pure chaparral of one type or another, anywhere you find the brush broken by trails, roads, powerlines, homesteads, etc., non-native brush can make its way into the mix. These non-natives tend to be much more flammable when dry than the native chaparral. So when it is mixed into the edge of a stand of chaparral, the non-natives can act as tinder to get the fire started which is then passed on to the more pure stands of chaparral. The chaparral is very resistant to fire, but when confronted by the blowtorch of flames being driven by 60MPH winds it will burn - as will any dry fuel, native, non-native, or structures.
I once saw a Jeep-load of teenagers having a contest to see who could throw a lit cigarette the farthest into the "brush" below our house. They also ran through the "brush" grabbing onto it for support while holding their cigarettes and I saw glowing tobacco brushed off by the very dry chaparral bushes. And it was September when things are extremely dry. Fortunately, that brush was all native chaparral and it did not ignite.
So if the non-native species were kept out of the mix alongside of
In summary what do I think should be done to prevent wildfires?
I'm tired of hearing all the claptrap about chaparral being a fire-dependent ecosystem which is designed to burn. That's just an excuse we use to blame something that cannot defend itself and allow us to keep hoping that our house won't be the next one to burn. We need to take the steps to prevent it from burning. That will be better for the chaparral, better for the birds and critters that depend on the chaparral, and better for all of us.
Sunday, November 18. 2007
The state of Idaho lost much more land to wildfires in 2007 than California did. They have had a big problem with cheat grass, an invasive non-native and highly flammable grass, so the state is sponsoring a volunteer program to gather seeds and plant sage brush over as much of the burned over area as possible. Here is a story about it. And here is a link to an NPR report on the program. I don't know how long they leave their stories posted, so read it fast!
Go Idaho! Good for you. Now how about California?...
Well, I don't know if we can ever cooperate on something like that, but there are lots of resources here for people who want to go it alone. Here is a site called WeedWatch. They want to combat invasive non-natives. It could become a valuable resource, but information alone will not solve the problem. You must USE it.
Wednesday, November 14. 2007
Here Dave Hogan talks about the effects of fire on chaparral and vice-versa. It's a very good interview recorded on-site on the edge of one of the burned areas. Listen soon before the clip disappears from the KPBS website...
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