MR. STEVE ROBERTSThanks for joining us. I'm Steve Roberts of George Washington University sitting in today for Diane Rehm. She's on vacation. She'll be back in this chair in the middle of September. Thousands of firefighters are working to contain the giant wildfire encroaching on Yosemite National Park in California. They've made some progress, but still, experts warned thousands of square miles remain at risk.

MR. STEVE ROBERTSHere to discuss the blaze and what can be done to better manage the wildfire is Robert Bonnie. He's the undersecretary of the U.S. Department of Agriculture. Norman Christensen is research professor and founding dean of the Nicholas School Division of Environmental Sciences & Policy at Duke University. He's also Robert Bonnie's former professor, I just learned. And by phone from Three Rivers, Calif., Jon Keeley at the Western Research Center of the U.S. Geological Survey. Gentlemen, welcome. Nice to have you on "The Diane Rehm Show."

PROF. NORMAN CHRISTENSENThank you.

MR. ROBERT BONNIEThank you.

PROF. JON KEELEYThank you. Good to be here.

ROBERTSYou can call us with your questions, your experiences, your comments, 1-800-433-8850. Drshow@wamu.org is our email address. We're on Twitter, Facebook. Give us a call. Join the conversation. Robert Bonnie, latest from the California this morning. They've now up to the estimate to 20 percent contained. What does that mean, and what's the situation on the ground as you know it?

BONNIEWell, so when forest -- when firefighters approach a fire they're trying to establishment containment lines along the edge of the fire. And so we had a good day yesterday. We were able to bump up containment from 7 percent to 20 percent. And what means is, is that the firefighters on the ground they're confident they can control that side of the fire. Importantly, the containment lines are close to where there are a large number of homes.

BONNIEThere's still other homes that are threatened by this fire as it continues to expand both to the north and south and as well to the east. It's at about 160,000 acres right now. There are about 37,000 firefighters on the fire, and that's a mix of state firefighters, federal firefighters. We've got a lot of federal assets, air tankers, helicopters on the fire continuing to work closely with the state there.

BONNIEThere remain evacuations in place, and some new ones that have been put into place. As I think folks have heard in the media, there are some considerable concern about some of the infrastructure there, both power lines and particularly Hetch Hetchy, which provides drinking water to San Francisco. So the Forest Service is continuing to work to -- with the state to suppress the fire there and to work on ensuring that that infrastructure remains workable, but there are some real challenges there.

ROBERTSAnd what are the challenges?

BONNIEWell, any time you have a fire like this in this type of fuel with wind and weather conditions the way they are, you're concerned about putting firefighters in front of the fire because the safety of our firefighters is always paramount. So we have to work with aerial resources and other resources to contain the fire, and obviously as we look at a fire like this, we're concerned about homes and lives. And we're also concerned about those infrastructure, and we'll continue to work there.

ROBERTSNow, you mentioned the conditions on the ground. Norman Christensen, the -- I know that this year, the level of fires is not unusual, but the longer-term trend has been toward longer fires, larger fires, larger burn acreage every year and a much longer fire season. It's expanded by several months. What's going on here in the longer-term picture?

CHRISTENSENWell, certainly -- and I should say that this year has been a really big year in many locations that clearly one of the issues is changes -- or are changes in climate, warmer and in many places drier conditions extending into periods of the year that have historically been somewhat more moist. And the moisture content of fuel is a really important issue. But associated with that are some other really important trends.

CHRISTENSENEvery year, we have more and more people living in wetland areas that are likely to be affected by fire. These people are sources of ignition. On the other hand, they're also very much a threat. So -- and probably a third factor at least in some particular locations has been changes in the nature of the fuels themselves that relate to historical management practices in some of the forests, not all, but some.

ROBERTSJon Keeley, of course, the debate about climate change is a hot topic here in Washington, but for forest managers on the ground, I gather there's not much debate that 2012 was the hottest year on record. And that even one degree increase in temperature can have a very sizable effect on the fire situations. Explain that to our listeners.

KEELEYWell, as Dr. Christensen indicated, moisture is extremely critical determining fire behavior, and the last -- not just the last year but the last almost two years the Sierra Nevada region has been undergoing a severe drought. There's -- it ties with the 1977, '76-'77 drought we had 35 years ago. And that is almost without doubt a major factor in the fire behavior because when you go through a sustained drought you not only have live fuels at very low moisture, but you increase the amount of dead fuels on the landscape.

KEELEYAnd that seems to be a major factor in these fires because most all the reports on the ground talk about the biggest problem they face are containing spot fires, which are when embers get blown ahead of the fire, and what is determinant in terms of whether they start a fire is how dry the fuel is as they land on. And so they're seeing lots of spotting behavior with this fire, which makes extremely difficult to contain.

ROBERTSNow, Robert Bonnie, of course, there's been a lot of attention to this fire at least in part because Yosemite is such an iconic landmark to many Americans. Many people have traveled there. But it's only one of 11 fires burning in California at the moment. But you mentioned one of the particular elements of this fire that has focused attention. Gov. Brown has declared a disaster in California because of the threat to the water supply of San Francisco.

ROBERTSThe Hetch Hetchy Reservoir, which actually known as a particularly pure source of water, and there's a lot of concern about how the ash from the fire could pollute the water supply. Talk about that element of it.

BONNIEYeah. So this is a challenge we face in many fires. There's the problem of the fires that's actually happening and the destruction you see from the fire itself, and then there are lingering impacts. And so in a watershed, like the Hetch Hetchy watershed, if you get a very hot fire, you take away the vegetation, you destroy a lot of the organic matter in the soils. And the soils when it rains the water washes off, carry soil, ash and other things in the watershed.

BONNIEIf you remember the Waldo Canyon fire last year in Colorado Springs and the aftermath of that fire, there were significant impacts to the watershed which the city of Colorado Springs relies on for its drinking water, same issue here. And in many Western states, millions and millions of people rely on their national forests and their public lands for their water. And in this case, we both have the short-term challenges of the direct threat from fire to Hetch Hetchy and to some of the infrastructure, power lines and other things around, Hetch Hetchy.

BONNIEBut then we've got the longer-term impacts. And so, you know, when the fire stops burning, there are a still lot more work to be done.

ROBERTSBecause in the rainy season, the rains would -- there's still ash on the ground and potential pollutants. That can wash into the water supply. So it doesn't end when the fire ends.

BONNIEThat's exactly right. And so as soon as the ground is cool, our teams working with the state and with other federal agencies will go out and begin the restoration process. But when you have a very destructive fire, that restoration process becomes more expensive but also more important.

ROBERTSNow, Norm Christensen, I know there's a lot of debate in the fire community about prevention and suppression techniques, about controlled burn, about the kinds of strategies that can somehow reduce the threat from fire. You mentioned that in your own remarks. What are we learning from a fire like this? What's working, and what's not working?

CHRISTENSENWell, it's -- I guess you'd say there are several issues at play here. We -- there are places in this fire, particularly in the forested areas, areas we call mixed conifer, where past management that is the suppression of fires has allowed the in-growth of shrubs and the accumulation of woody fuels which makes these areas not only more flammable but makes -- or allows for the fires that burn to be much more severe.

CHRISTENSENAnd so we could arguably and in many places I should say in the Sierras there have been efforts made to restore historic fuel conditions, literally come in at considerable expense and clear out that woody debris to make these forests less apt to burn severely. We should that these -- that fire in these forests are nevertheless a natural phenomenon, but historically, those fires burn not up in the crowns of the trees but largely along the ground.

CHRISTENSENThat's a characteristic. And in this particular region, a characteristic of forests on the somewhat more moisture smoke on the south facing very dry slopes. This area is dominated by shrub lands, by chaparral and sage. Here, past management hasn't probably had any effect at all. It's just -- and that really intense fires at various intervals are an important and longstanding part of those ecosystems. Here -- so here, our management options are somewhat more restricted. Prescribed fire in this particular situation is usually not an option.

ROBERTSThat's Norman Christensen. He's a professor at Duke. Also with me, Robert Bonnie. He's the undersecretary of agriculture, and on the phone from California, Jon Keeley from the Western Research Center of the U.S. Geological Survey. I'm Steve Roberts sitting in for Diane. We'll be right back.

ROBERTSWelcome back. I'm Steve Roberts, sitting in today for Diane. And our subject this hour, the wild fires in California, particularly the one threatening Yosemite National Park. I have three experts with me to talk about this: Norm Christensen from Duke University, Robert Bonnie's in the studio. He's the undersecretary of agriculture. And by phone from Three Rivers, Calif., Jon Keeley from the U.S. Geological Survey.

ROBERTSWe have some lines open. Give us a call, 1-800-433-8850, drshow@wamu.org is our email address. And, Jon Keeley, one of the -- Robert Bonnie was talking about protecting the Hetch Hetchy Reservoir. Another iconic element to this fire, of course, are the old redwood stands. There are a number of them in the Yosemite Park. Now, I read one commentator who said, well, they've lived for 200 years.

ROBERTSThey probably have a certain resistance to fire. But I'm sure a lot of listeners would say, what about the redwoods? And are they in danger? And what can you tell us about them?

KEELEYWell, there's isolated groves of giant sequoias throughout Yosemite Park. And I'm not certain of the distribution rounds for this fire, so I don't know if there's any immediately threatened. But the Park Service has been addressing that issue for at least three or four decades by doing understory prescription burning in -- largely focused on giant sequoia groves as a way of protecting them. And so far, it seems to be highly successful.

KEELEYAnd in this fire in particular, you can see the role of those prescribed burns because the Rim Fire in the north -- I guess it's the northeast corner -- ran into two of these prescribed burns that have been done in the park. And now the fire is just creeping between those two prescribed burns and pretty much staying out of those areas. So it illustrates the success of the prescription burn program in terms of protecting forest resources.

ROBERTSRobert Bonnie, you agree the redwood's pretty much safe?

BONNIEYeah, I think so. I think there's a broader point here that I wanna get back to that Norm talked about, which is forest restoration. We've got a number of places, particularly in these dry forests throughout the west where we can do more in the woods to deal with some of the lingering effects from fire suppression that has been carried on for a long, long time and caused those fuels to build up.

BONNIEAnd there are actually some real opportunities to work in partnership with conservation groups, with the timber industry, with local communities to try and get more work done in the woods in a way that it'll make those forests more resilient, that will allow us to get the lower intensity burns that Norm talked about back into the woods. And I think we also have to recognize that we need to do this at a large enough scale.

BONNIESo we need to work at large landscapes in order to have an impact on this. And we need to target it particularly in places the wildland have been interfaced again that Norm talked about, where we've got people living on the edge of forest so we can do this in a way that will reduce the intensity of fire in those areas. And I think that's a very critical element. It's something that Secretary Vilsack has talked a lot about and I think a real emphasis of the Forest Service going forward.

ROBERTSWell, one of the points you make here about the encroachment of structures on these previous wildlands is a very important variable here, including driving up the cost of fighting these fires because I gather you have to devote a lot of resources to protecting structures that are now far more vulnerable than they might have been earlier. And a lot of stories over the summer have said basically, the Forest Service have ran out of money for fighting fires in part because of the encroachment structures. Elaborate on that point.

BONNIESo we haven't run out of money, and we won't. We'll continue to devote the resources to firefighting that we need. The challenge we have is that the forest service in bad fire years, last year and again this year, has to transfer money from non-firefighting accounts to pay for firefighting. So last year, we transferred about $440 million from non-firefighting accounts into the fire suppression line of the Forest Service budget. This year, we will -- we're prepared, and it started transferring money.

BONNIEWe may transfer as much as $600 million. The long-term challenge for the Forest Service beyond the immediate problems of taking money from other programs is that the fire program has grown over time. So that whereas firefighting used to be 10 to 15 percent of the Forest Service budget, it's now normally more than 40 percent, and this year, we'll probably be close to 50 percent. So as we've increased fire resources, we've had a necessarily reduce management resources.

ROBERTSSure.

BONNIEAnd so it's harder to get the work done that we need to actually prevent the firefighting. This is something that the president talked about in his climate change speech several weeks ago. It's something that the -- Secretary Vilsack has talked about. And we need to get to a place where we stop treating fires as a normal budget expense, which is the way we treat them now, and start treating them like the natural disaster that they are.

ROBERTSNow, Norm Christensen, you raised the point about structures being built more and more in wilder lands. We saw this in other fires in Arizona earlier in the summer, the tragedy in Yarnell of 19 firefighters killed, in part because those communities were being threatened, and they were on the line and vulnerable. Do we need to revisit policies about the restricting in where people can build homes? Is there more to be done about making people responsible, more responsible in terms of the materials they use and other elements of this larger picture?

CHRISTENSENYou know, I think the answer is maybe a qualified yes. We have strong traditions in this country about managing where people live and talk to people who live in wild areas. I live in the woods of North Carolina. We love these areas. But I also think we probably don't do enough to have people accept the full responsibility of the decision we make about where we live so that the costs are sometimes, if you will, external to the landowners, and there are really significant costs. There are...

ROBERTSWell, what could be done? What would you suggest that would be done? One idea that I've heard about is more requirements in terms of fire-resistant materials, but what else?

CHRISTENSENAnd that -- number one, that would be really important. There are great programs, fire-wise program. For example, the National Forest Service manages -- provide those guidelines. There are many communities in the West that, at the county level, have set in-building codes, those kinds of regulations. I think insurance companies can do a great bit here. This is an area that -- where insurance -- the private insurance companies have a really significant role to play in changing behavior.

CHRISTENSENIn really intense fires, though, even these protected structures are still going to be at really high risk. And so the fact that we have so many people out there even with the best construction will still present a variety of issues for managing wild areas for managing fire.

ROBERTSAnd, Jon Keeley, talk about the dimension and prevention. We all grew up with Smokey the Bear, and only you can prevent fire -- forest fires. I haven't heard of Smokey lately. Is there still an ongoing prevention program? And what is the latest that people have learned about the most -- I'm sure there are listeners out there who would like to know, you know, if only you can't prevent forest fires, what should people know when they go out into the woods? It's still summer, still people out enjoying the wilderness. What should they know, Jon?

KEELEYWell, I think there is no question that prevention is absolutely critical, and it's probably one of the two things that we can do to minimize losses. We see that in Southern California, in particular. We've -- we have probably the worst region of anywhere in the world in terms of housing losses from fires. In the last 10 years, we've averaged 1,000 homes a year lost from fire. So we've learned about...

ROBERTSI lived in Southern California. I was evacuated twice from fire -- by -- from my home by fires. I know what you're talking about.

KEELEYYeah, that's a common autumn experience for people in Southern California, and it's a critically important issue in terms where homes are located. And USGS has just released a film called "Living with Fire" that can be downloaded, if you're interested in, that talks about...

ROBERTSWhere can people find that on what website?

KEELEYIf they go to the US Geological Survey Western Ecological Research Center website, they'll be able to find it.

ROBERTSGood.

KEELEYAnd this -- the focus of this film is all about the dual roles of fire prevention and better land planning. And one of the keys to reducing housing losses is, I think, to follow suggestions in a book by Roger Kennedy. He was a former National Park Service director who wrote a book that talks about the issue of fire zoning and if comparable to the idea of flood zoning, where you find parts of the environment where you know you're likely to see fires and try and avoid those in terms of where you plan developments.

KEELEYAnd we've looked at in some regions in Southern California the factors that are most responsible for housing loss, and location seems to be the one issue that comes up repeatedly that there are certain areas that repeatedly are hit by fires. And we need to factor that into zoning decisions as well as coupling it with the appropriate type of fuel treatment. And a good illustration of appropriate fuel treatment is observed in the Springs fire in Ventura County that occurred in May.

KEELEYIt was a very large wildfire driven by these extreme Santa Ana winds. Not a single home was lost in that fire. And recently, I was on a field trip with Ventura Fire Department, and, you know, they went around to these homes and showed that the homeowners had done very good clearance around the homes, 100 foot, where everything is taken down to bare ground. And that seems to be a key factor.

KEELEYAnd in those environments, probably fuel treatments at the house, wildland interface is probably the key to saving structures as opposed to doing treatments throughout the landscape, which is often a strategy that's followed.

ROBERTSWell, you know, of course, this is not a new issue. We -- it comes up all the time on floodplains and other vulnerable areas where people return again and again and building houses on places that are geologically vulnerable but also comes up again and again. And Norm Christensen talked about to lure the woods and the -- is a sense of home, a sense of place, and people are drawn back to these places even when they know they're vulnerable.

KEELEYOh, yes. People do wanna rebuild right after fires. And, you know, you can't blame them because that's what they associate as homes. But I think this recent Rim Fire illustrates an important point about fuel treatments for affecting fire behavior. The fuel treatments at the interface between urban and wildland areas is without a doubt effective in many instances in reducing losses.

KEELEYBut there is a lot of effort going in to doing fuel treatments across the landscape, and that's not always effective, and the Rim Fire is a good illustration. The nice thing about the Internet these days is one can pull up a Google Earth image of the area that just burned in the Rim Fire, and one of the things you see in that is the Forest Service lands, they're of multi-use, where they've been -- had a lot of management subjected to them, not just fire suppression but logging activities.

KEELEYAnd there's -- I count something like 25 large patches of clear-cut in that area. And what that illustrates is that modifying those fuels to the level of clear-cutting the forest didn't stop the fire. The fire just simply found a way around it. Now, that doesn't mean areas like that don't have any value. They potentially provide defensible space for fighting fires. But in this instance, they were so remote that they weren't really accessible, and they didn't stop the fire. And so there's a lot of reason to focus on the wildland-urban interface...

ROBERTSRight.

KEELEY...in terms of doing these treatments.

ROBERTSI'm Steve Roberts, and you're listening to "The Diane Rehm Show." Robert Bonnie, so much talk here about prevention and strategies, but you just talked about your budget. You just talked about the fact that more and more every year, your budget is eaten up by the necessity to fight these fires, now over 40 percent. I saw a figure, 47 percent. Is that reducing your ability to do these longer-term strategies in terms of both research and in-the-field activities?

BONNIEYeah. I mean, absolutely. And I think a key element of our ability to do these treatments, both in the wildland-urban interface and other areas where, you know, we're doing these forest restoration projects, it's certainly dependent on budget. We're gonna have to get better at being more efficient in the work we do. So one of the strategies is to look at larger areas and to do larger projects where we can spread the cost and do them in partnerships with local communities and conservation groups and forest industry and others.

BONNIEYou know, as I think everybody knows, forest management has at times been very controversial in the West. I think our strategy to deal with that is to bring folks together, to look for collaborative ways to do large-scale restoration. And I think it's right -- Jon's right to say there are areas to focus on in the wildland-urban interface that will continue to be an effort.

BONNIEBut there are forest types in the West as well where I think we can reduce the chances of catastrophic fire and also make those forests more resilient by ensuring that we're using the best science and that we're managing lands in a way that make forests more resilient, both from a fire standpoint, but from an ecological standpoint as well.

ROBERTSNow, another point you mentioned earlier was the prime importance you place on the safety of the firefighters. Of course earlier this summer, we had such a tragic reminder in Yarnell, Ariz., 19 Hotshots lost, and I gather there were several other deaths...

BONNIEYes.

ROBERTS...around the West as well this summer. What have you learned from that fire and incidents like that? There's a high death toll. Are you doing anything different today than you did at the beginning of the summer, new directives, new lessons learned from that tragedy?

BONNIESo the -- after Yarnell Hill, there's a state investigation being led by the state. That's -- that fire was being managed by the state at the time. We were providing considerable federal resources. That was not a Forest Service crew, but, you know, our hearts obviously go out to the families and the firefighters there. The fire community's a tight-knit community, and I...

ROBERTSI have a niece who's a Hotshot, a Forest Service Hotshot, and I know this directly.

BONNIEIt's obviously a great tragedy. After every tragedy like that, we try and learn everything we can from it. From -- so from an operational standpoint, we can learn and be more safe in the future. I was at the Lolo fire in Lolo, Mont., last week, just south of Missoula, and the emphasis on safety is -- continues to be in -- critical and emphasized to all the firefighters. In the case of the Yarnell Hill fire and the Granite Mountain Hotshots, we'll see what the state investigation says.

BONNIEBut we obviously take those -- we'll take those lessons, and just as we have done in past fatalities, we will blend them into the direction we're giving our fighters on the ground just to make sure safety is -- continues to be paramount.

ROBERTSVery quickly, Jon Keeley. You learned anything from Yarnell that you think is important?

KEELEYWell, it's a tragedy. There's no question about it, and I don't know enough specifics about that event to really comment on it.

ROBERTSOK. Great. Jon Keeley, he's at the Western Research Center of the U.S. Geological Survey. You also heard from Norm Christensen, who teaches at Duke University. And here with me in the studio, Robert Bonnie. He's the undersecretary at the U.S. Department of Agriculture. I'm Steve Roberts, sitting in today for Diane. Your calls are next, so stay with us.

ROBERTSWelcome back. I'm Steve Roberts, sitting in today for Diane. Our subject this hour: the wildfires in California, particularly the one that is burning swaths of Yosemite National Park, a place where many of you have visited. And I have three guests who we're talking on this subject. Robert Bonnie is the undersecretary at the U.S. Department of Agriculture. Norm Christensen teaches at Duke. Jon Keeley is at the Western Research Center of the U.S. Geological Survey. Our phone number, 1-800-433-8850. Drshow@wamu.org is our email address.

ROBERTSAnd let me read this email. It comes from Alwyn (sp?) in Blacksburg, Va. "Thanks for this show. I would like to know what is happening to the wildlife in Yosemite. There has been almost no coverage on this aspect to the fire in Yosemite or any of the other major fires the media have tried to -- that I have tried to cover. I'd be very grateful to any information on the ways wildlife is or is unable to cope with these fires." Any of you have an answer for Alwyn? No, you're all...

CHRISTENSENMy comment...

ROBERTSGo ahead, please.

CHRISTENSENJust a comment that in most fire situations, wildlife -- mammals, birds -- are remarkably well-adapted. They move instinctively in ways so that the direct impacts are relatively small. I think the concerns about wildlife, particularly in exceedingly large fires, might be post-fire issues in terms of habitat and habitat loss. And Jon Keeley may know more about those specific issues.

ROBERTSJon, you got something to add here?

KEELEYWell, there's no question the really critical factor in terms of impacts to the wildlife is the pattern of burning because most animals have to flee the fire, and those who don't flee the fire, those areas have to be repopulated by animals that re-colonize from other populations. So if the fire -- the pattern of burning is really critical. If there are patches of area unburned, adjacent to burned areas, that's ideal in terms of re-colonization.

KEELEYAnd in this case, certainly where the fire hit the national park and there were there these prescribed burns that had been done in previous years and the fire died out, those will be critically important source populations for animals moving back into the burned area.

ROBERTSPatrick writes to us, "Why are explicit efforts to protect ancient trees -- sequoias, redwoods -- a part of modern fire forest fighting in the Western U.S. if these trees have successfully lived for so long without our help?" Robert Bonnie.

BONNIEWell, I think that's an important point. One of the things you try and do in these -- in some of the treatments we're talking about is protect the large trees that tend to be far more fire-resilient. The challenge you have in a lot of these ecosystems is because you have had fire suppression for so many years, you've, in essence, created some unnatural conditions that make them more vulnerable to fire and make them less likely to have the type of fire that is the cool, less-destructive ground fire and more likely to have fires that go into the crown. And that's why...

ROBERTSYou keep using that phrase fire suppression, but I'm not sure I understand exactly what you mean.

BONNIESo when we think about fire suppression, we think about, for years, the Forest Service and other federal agencies and really the entire forest community was intent on putting out every fire, even the fires that were beneficial to ecosystems. And so when you do that, fuels, small woody bushes and trees and other things grow up. And so in order to kind of reset the clock, we actually have to go in and do some manipulations in those ecosystems to open them back up.

BONNIEYou look at old pictures of ponderosa pine forests, a large major ecosystem in the West and they were open, park-like stands, and that was because fire kept them that way. Every five or 10 years, those sites burned. When you suppress fire, when you put out every fire for decades, you change that ecosystem in a way where in order to get the natural fire back in, we really have to go do manipulations.

BONNIEAnd so it's been many years since the Forest Service and other federal agencies and state agencies have gotten away from that dogma of putting out every fire, but we still have lingering effects that we have to deal with.

ROBERTSWe have an email from David Cooper in Hedgesville, W.Va. "Just as with flood insurance" -- a point we made earlier -- "fire insurance enables people to live in areas where they should not have a residence. This not only causes other insurance purchasers and/or taxpayers more expense, but it risks fire fighters' lives as they make extra effort to protect lives and property. We need to stop this enabling.

ROBERTSIf one chooses to live in a designated fire or flood area, those already there get to collect only once. New residents should get no subsidized insurance." Norm Christensen, you were talking about this issue. Please answer David.

CHRISTENSENYeah. You know, I think that's maybe, I could say, a nice idea in theory but a difficult idea to put in practice. I was recently in a meeting with fire survivors of the High Park fire in Colorado last year. All of these people had their homes built and were rebuilding. And one of the people made a comment that we all live in places that, in one way or another, are -- risks threat of damage from nature, whether it's an earthquake, whether we live on the coast and it's a hurricane or ice storms in the Northeast.

CHRISTENSENThe -- so I think the idea that people should take responsibility for the individual risk that they face and that insurance represents an important tool for doing that is important. But it's -- I think it's difficult to say, well, we won't provide insurance. Now, certainly that's a decision that actually resides at the level of the individual insurance -- or insurers. So there are probably decisions of that kind that may already being made.

ROBERTSLet's turn to some of our callers. And Sue in Dallas, Texas, you're first. Welcome. You're on "The Diane Rehm Show."

SUEHi. And good program. Thank you. I have some property in East Texas and it -- I have pines and hardwood mix and -- on different parts of the property but patches of ferns, you know what I'm talking about. And when we had our drought two years ago, it was so severe that it killed a lot of my pine tree. The locals tell me I should just let them fall and replenish the soil and provide habitat. But from all of your discussion, I have some concerns that I'm just creating more kindling, and I don't know what the responsible thing to do would be. So can you give me a little more guidance, please?

ROBERTSSue, thanks very much for your call. Jon Keeley.

KEELEYWell, there's no question that mortality of trees contributes to fuel load on the landscape, and that potentially makes the possibility of disastrous fires go up. How to best treat it depends on, you know, your particular landscape and the ecosystem. There are some forests in the west where when trees die, they present a critical hazard for the first few years because they have very fine needles and branches, and those create conditions for easy ignitions and fire spread.

KEELEYOnce the trees drop those fuels and you're left with just a dead trunk, oftentimes that's much less of a hazard. So it just depends on your particular situation. But I know there are many firefighters that would advice one to take dead trees out.

ROBERTSThanks, Sue. We appreciate your call.

SUEThanks.

ROBERTSLet's turn to Marion in Roachdale, Ind. Marion, welcome. You're on "The Diane Rehm Show."

MARIONThank you so much. In all reverence for the firefighters and all of you who I know love the Earth and the animals and all of us and the work that you're doing. I'm a nurse and health educator, and I work with the Hoosiers for Healthy Animal Agriculture in Indiana. And as we talk about prevention, I wanna remind everybody that I am witnessing the big agricultural farming industry destroy millions of acres of pasture and woodland in Indiana where we are going to be a desert right now.

MARIONI live in Tornado Alley and a farm -- a fire range because of these modern farming practices that now our legislature is passing even more right to farm laws, allowing this devastation of the land. And people need to know that we can prevent forest fires by changing our food habits and by changing our lifestyle and realizing that our urban areas are also going to be desert in five years. The farmers around here don't even believe in global warming. You talk about that, they say we don't care. I cannot farm organically because of poison from the USDA-sponsored farming.

ROBERTSOK.

MARIONI would like to hear this addressed when we talk about these fires. And I have a family member that's a firefighter, so this touches home.

ROBERTSThank you very much, Marion. We appreciate your call. Robert Bonnie, do you have a response?

BONNIEYeah, I mean, I think -- look, we got to grow food, and we have to, you know, we've got to feed nine billion people by 2050. And so there's a critically important role for agriculture on our landscape, an intensive agriculture on our landscape. But it can be done in a way that protects soil resources, that protects water resources.

BONNIEEvery year, USDA spends billions of dollars working with farmers and partnership with conservation groups and others to do just that, to make sure that agriculture is done in a way that not only produces the food we need but that also protects our soil and water resources. There are more we can do, absolutely. But I think, you know, there's a great tradition of stewardship and conservation amongst farmers, ranchers and our private working forest owners in United States.

ROBERTSLet's turn to Jared in Jeffersonville, Ind. Jared, welcome. You're on "The Diane Rehm Show."

JAREDThank you very much, Steve. You stole my original question, so I guess great minds think alike. But my question would be kinda similar to the last caller. What type of regulations or challenges do managers face in a residential privately owned woodland, agricultural that creates challenges to kind of prevent these larger fires?

ROBERTSAll right, Jared. thanks very much. Norm?

CHRISTENSENYou know, it's interesting. It's something we haven't talked about. And this is a particular issue in California, as Jon is well aware, the effect of fire on air quality. We've talked about the direct threats that fires present to structures and so forth.

ROBERTSAnd we talked a bit about the threat to water resources as well.

CHRISTENSENAnd water resources. And -- but they -- I grew up in the Central Valley, and I still have family there. The Central Valley in the summertime experiences some of the worst air quality -- in California that is -- the -- some of the worst air quality in the entire country. Fires add to that pollution load. It's a matter that restricts our management in many cases, our ability to do, for example, prescribed burning and particularly the lower elevations of the Sierra Nevada are often influenced by air quality regulations.

CHRISTENSENAnd that's true, as a matter of fact, across the entire country. I live here in North Carolina. We use prescribed fire a great deal, but our ability to do that is really limited by air quality issues. So the development, if you will, of increased human population creates a variety of issues that -- including the air quality. I've should mention...

ROBERTSHold on just one second. Hold on for just second here.

CHRISTENSENYeah. Sure.

ROBERTSI'm Steve Roberts, and you're listening to "The Diane Rehm Show." Go ahead, Norm.

CHRISTENSENOh, I just wanted to also to call attention just so we're clear. At the moment the Rim Fire is burning beneath or at lower elevations than Hetch Hetchy, so the -- it would be a threat to Hetch Hetchy Reservoir, the kind of erosion, if that fire were to move up to higher elevations. So there are number of reservoirs, however, at lower elevations that will be definitely affected by this fire.

ROBERTSLet's talk to Eddie in Pittsburg, Pa. Eddie, welcome. You're on "The Diane Rehm Show."

EDDIEThanks very much. I love the program in general and today specifically. And I have to say that I agree with the email -- emailer a while ago about insurance, which just tends to perpetuate the foolish decision of moving back and rebuilding into areas, whether they'd be coastal flooding areas or high-danger forest fire areas. And I certainly believe that no taxpayer money should go into that insurance to subsidize it. That's one point. The second point I wanna make is that -- your guests can correct me if my figures are a little bit off.

EDDIEBut approximately two-thirds of the water in the United States falls east of the Mississippi, meeting about one-third for about two-thirds of the land mass. Here in Pennsylvania, we have 38 inches of rain and we have the forest to show it. They're extremely verdant, and we have 17 million acres of forest land here. Fire threats are minimal here. The point being that our land use policy allows people to go to areas where they shouldn't really live.

EDDIEMaybe we should be guests in the forest, you know, and have more wilderness areas where you can just look at things for a while and not say, oh, I have to it, I have to it, I have live there.

ROBERTSEddie, thanks very much for your call. Jon Keeley, a response.

KEELEYWell, there are two important issues that the caller brought up. One has to do with insurance. And that's a tricky issue because -- particularly in our part of the world. There is a level of subsidy given to homeowners who live in dangerous areas where insurance companies may not consider them safe areas for insuring. But they have something called the California FAIR Plan, which basically insurance companies get together and they subsidize these people in large part because they want to avoid legislation that would perhaps force that on them.

KEELEYThat -- that's a contributor. But I think the bigger issue and the more important one the caller brought up is one on planning. And one of the issues that we make in the USGS movie I mentioned is we're looking at homes today that are burning that 50 years ago they didn't exist. And the homes that we're gonna see burning in the future, they haven't been built yet. And so we now have an opportunity to change the future by thinking more clearly about where we allow homes to be built.

KEELEYAnd I suggest, you know, flood research is shown as one important thing. And that is floods don't occur everywhere. They occur in certain areas, and we need to zone those areas to keep people out of them. And to some extent, the same is true in terms of wildfires. There are certain areas that are hazardous, and we ought to give more thought to planning where we put development.

ROBERTSThat has to be the last word. Jon Keeley from Western Research Center at the U.S. Geological Survey, Norm Christensen from Duke University, Robert Bonnie, who's the undersecretary at the U.S. Department of Agriculture, thank you all for being with us on this hour of "The Diane Rehm Show." I'm Steve Roberts, sitting in today for Diane. She's on vacation. She'll be back in mid-September. And thanks so much for spending an hour of your morning with us.