- Author: ESPM News
In response to California's growing tree mortality crisis, the Little Hoover Commission held a public hearing on California Forest Management yesterday (January 26) at the state capital in Sacramento.
Professor Scott Stephens, a fire scientist in the department of environmental science, policy, and management, delivered the opening remarks. He provided background on the causes and magnitude of tree losses happening across the state. "Our forests are not in a resilient condition," he said. "Past management actions, including fire suppression and logging focused on large trees have produced forests today that are much more vulnerable to fire and drought-related mortality." Stephens made suggestions for legislation, policy, and forest management techniques that could help restore resilience to California's forest ecosystems and prevent future mortality crises. He also offered ideas on how the state could better work with private landowners as well as the federal government to promote healthier forests.
- Author: Robert Sanders
Reposted from UC Berkeley News
An unprecedented 40-year experiment in a 40,000-acre valley of Yosemite National Park strongly supports the idea that managing fire, rather than suppressing it, makes wilderness areas more resilient to fire, with the added benefit of increased water availability and resistance to drought.
After a three-year, on-the-ground assessment of the park's Illilouette Creek basin, UC Berkeley researchers concluded that a strategy dating to 1973 of managing wildfires with minimal suppression and almost no preemptive, so-called prescribed burns has created a landscape more resistant to catastrophic fire, with more diverse vegetation and forest structure and increased water storage, mostly in the form of meadows in areas cleared by fires.
“When fire is not suppressed, you get all these benefits: increased stream flow, increased downstream water availability, increased soil moisture, which improves habitat for the plants within the watershed. And it increases the drought resistance of the remaining trees and also increases the fire resilience because you have created these natural firebreaks,” said Gabrielle Boisramé, a graduate student in UC Berkeley's Department of Civil and Environmental Engineering and first author of the study.
Boisramé and co-author Sally Thompson, a UC Berkeley ecohydrologist and assistant professor of civil and environmental engineering, found that even in the drought years covered by the study, the basin retained more water than similar areas outside the park. That translated into more runoff into the Upper Merced River, which flows through Yosemite Valley, at a time when other rivers in the surrounding areas without a restored fire regime showed the same or decreased flow.
“We know that forests are deep-rooted and that they have a large leaf area, which means they are both thirsty and able to get to water resources,” Thompson said. “So if fire removes 20 percent of that demand from the landscape, that frees up some of the water to do different things, from recharging groundwater resources to supporting different kinds of vegetation, and it could start to move into the surface water supplies as stream flow.”
The study is published in the current issue of the journal Ecosystems.
If the results are confirmed from other studies, including the UC Berkeley team's new project analyzing the Sugarloaf Creek Basin in Sequoia and Kings Canyon national parks, they could alter the way the federal government as well as water districts deal with fire, benefiting not only the forest environment but potentially also agriculture and cities because of more runoff into streams and reservoirs.
“I think it has the potential to change the conversation about wildfire management,” said co-author Scott Stephens, a fire expert and UC Berkeley professor of environmental science, policy and management who has studied the Illilouette basin since 2002.
This “wildfire management” strategy is counter to the federal government's 110-year-old Smokey Bear policy, which is followed throughout the West and emphasizes suppressing fires wherever they occur for fear they will get out of control. With persistent drought and a warming climate, the U.S. Forest Service budget is increasingly going to firefighting. On most federal land, only forest thinning and human-initiated prescribed burns are allowed as a way to manage the trees and underbrush.
Stephens noted, however, that these agencies have recognized the folly of total suppression — thanks in part to his own studies throughout the Sierra Nevada over several decades — and current draft wildland management policies for three of the state's national forests allow active wildfire management in up to 60 percent of the forests.
The value of forest clearings
Wildfire management, as opposed to suppression, comes with major changes in the way the forest looks, Stephens and Thompson said. Unlike the dense stands of pine and fir most people associate with Yosemite and similar mid-elevation Sierra Nevada and Rocky Mountain forests, the Illilouette Creek basin has thinner forests and more clearings with dead trees.
“There is much more dramatic structural change in this forest than most people would probably feel comfortable with,” he said. “You are talking about low-density forests and gaps of 4 or 5 acres, up to maybe 100 acres. These are the result of major fires about every decade or so, large enough to cause tree scarring and affecting as much as one-quarter of the basin.”
These fire-caused clearings, however, act as natural fire breaks and make the area resistant to catastrophic fires such as the 2013 Rim Fire in the western part of the park, which burned 250,000 acres and left patches up to 20,000 acres in which not a single conifer tree survived. These areas could take a century to recover, Stephens said.
“In the Illilouette basin we lost about 20 percent of the forest cover, but there was a 200 percent increase in wetland vegetation: meadows starting to reemerge from forests that have probably encroached on historical locations,” Thompson said. “That sets us up to think that this new regime should be leakier as far as water goes — leaky in the way that suits us as a society.”
Even if these wildfire management techniques don't produce more runoff, Thompson added, “I think it is a fabulous result in terms of forest management if you end up with a healthier forest with some better intact aquatic habitat, even if you don't see a drop of water further downstream. It is still the right thing to do from an ecological point of view.
“Bottom line, this strategy might be a triple win-win-win for water, forest structure and fire risk,” she said.
The ‘jewel' of Yosemite National Park
The findings are the culmination of a 14-year study led by Stephens and his UC Berkeley colleagues to learn how monitoring natural, lightning-caused fires with a bias toward letting them burn affects the landscape, the vegetation and the groundwater. Only four areas in the western U.S., including two in California — the Illilouette Creek basin and the Sugarloaf Creek basin — have allowed lightning fires to burn in large areas for decades.
Most studies of different ways to manage wildland fires have been limited to a few hundred acres, and it's hard to extrapolate from such limited experiments to an entire forest. Luckily, Yosemite National Park started its experiment in 1973 — spurred by a 1963 report authored by the late UC Berkeley forester Starker Leopold — to let nature take its course in the Illilouette Creek watershed, stepping in only when fires in the basin threatened to get out of control or sent too much smoke into Yosemite Valley two miles to the northwest.
“This is the first study that looks at fire regime restoration on a watershed scale with empirical data,” he said. “Others do smaller areas or modeling, but this is 40,000 acres — a big place — over many years.”
One reason the basin was chosen was that it was surrounded by granite walls, which naturally prevented fires from spreading outside the basin. It had not been burned by the indigenous tribes of the region, which often set fires to increase acorn production, and had no history of prescribed burns. In fact, it saw only natural, lightning-caused fires except for an interval of nearly a century — 1875 to 1972 — when the park suppressed all fires.
While Stephens and his many students documented the changes in fire over the past 400 years, Boisramé and Thompson analyzed aerial photos to document vegetation change. Then, with the help of installed sensors and more than 3,000 soil moisture measurements throughout the basin, the team was able to estimate the amount of water in the landscape today versus in the past. They found similar or marginally drier conditions where forests had been replaced with shrubs, but these were balanced by much wetter conditions in small areas where meadows expanded.
They observed more snow reaching the ground because of the clearings, and more snow remaining during the spring, delaying runoff. And in recent drought years, when surrounding basins saw more trees die, there was almost no tree mortality in the Illilouette basin.
“In order to really understand whether this approach should be part of our management toolkit, I would recommend that we give it a crack in a few other places,” Thompson said. “This appears to be a promising management strategy without significant harm and with several very strongly quantifiable benefits and several very suggestive outcomes.”
Boisramé, who spent the past four summers sampling and camping in the Illilouette Creek basin, emphasized that this is not a strategy that would work everywhere. But in wilderness areas where wildfire management is being considered because of its safety benefits — to reduce underbrush and eliminate fuel for out-of-control and catastrophic fires that risk lives and property — the ecological and hydrological benefits are a big bonus. Areas with similar elevation and climatic conditions to the Illilouette basin, and thus perhaps suitable for managed wildfire, comprise about 18 percent of the Sierra Nevada, though the strategy may work at lower elevations as well.
“The whole ecosystem will be better off if we let the natural fire process back in,” she said.
The research was supported by a grant from the federal Joint Fire Science Program.
- Author: Jeannette Warnert
Reposted from the UCANR News Blog
Even though there has been a deficit of fire in California forests for decades, their future is not hopeless, said UC Berkeley fire science professor and UC Agriculture and Natural Resources researcher Scott Stephens in an interview with Craig Miller on KQED Science.
"The next 25 to 30 years are paramount. If you begin to do restoration, reduce density, make forests more variable in pattern, and less fuel, when you have episodes of drought and fire, it's going to be fine. The forests have been doing this for millennia. It's going to be fine," Stephens said.
However, under current conditions, in which fires have been regularly suppressed, the situation is dire.
"The forests used to burn every 12 to 15 years, but most places haven't been touched for 50 to 100 years. Today we have areas with 300 or 400 trees per acre, where you used to have 50 to 80," he said.
Even though, Stephens said he is an optimist. "There's still opportunity today to do restoration, so that when it does get warmer and warmer, as projected, the forests will be able to deal with that, deal with insects and disease and keep themselves intact."
- Author: Glen Martin
Reprinted from California Magazine
The recent rains have blunted the psychological impact of California's four-year drought, washing down the streets, perking up the landscaping, and heightening anticipation for a stormy El Nino-driven winter. We know, however, that one wet year is highly unlikely to end water shortages. What we may not fully grasp is that the damage done to the state's forests is so far reaching that it may be permanent.
How bad is it? Really, really bad. Horrendous, in fact. Sally Thompson, an assistant professor in UC Berkeley's department of civil and environmental engineering, cites the status of the state's iconic giant sequoias as an example. Thompson notes that Cal biology professor Todd Dawson has been monitoring the biggest trees on earth, “and has found that they're extremely stressed. They're dropping leaves—some of them may die. These are trees that have lived 3,000 years, enduring a wide range of environmental conditions, including other droughts. And now they're being killed by this drought. That's suggestive of what we're facing. We're heading into uncharted territory.”
And it's not just giant sequoias. Virtually all of California's trees are drought-stressed, and many are going down for the count. Thompson observes the U.S. Forest Service conducted flights over 8.3 million acres of woodland in the southern Sierra, the Central Coast and Southern California in April and concluded that about 10 percent of the conifers and oaks—about 12.5 million trees—had died in recent months. They had either expired directly from drought or succumbed to bark beetles, which attack weakened trees.
The situation has only grown more grim. Two weeks ago, Gov. Jerry Brown declared a state of emergency, warning that the U.S. Forest Service estimates “more than 22 million trees are dead and that tens of millions more are likely to die by the end of this year.” He asked for federal assistance and called for an accelerated program to cut and clear dead trees, expand the practice of prescribed burns and temporarily allow more burning of wood waste.
Greg Asner, a biologist with the Carnegie Institute for Science, used spectrometers and lasers to evaluate forest canopies on flights out of Sacramento and Bakersfield. The procedures yielded 3-D topographic displays that show the forest in varying shades of blue (healthy) yellow (somewhat stressed) and red (deeply stressed to dying or dead). Bottom line: There's a lot of red in them thar hills. Asner concluded about 20 percent of California's forests are doomed—up to 120 million trees.
The images reveal the trees are dying in a mosaic pattern, says Thompson.
“You'll see patches of dying trees in the middle of healthier forest,” she says. “That's probably due to such things as south-facing slopes or shallow soils. You'd expect such areas to experience (drought-related) stress first. But there's a tremendous volume of dead wood building up all across the forests, and that's pointing to a future that is potentially very
Such a vast accumulation of fuels could lead to wildfires that are perhaps unprecedented in their ferocity. They could be so intense and of such a vast scale that they could lead to broad “ecotonal shift” —the evolution of entire forests from one vegetative regime to another. Ponderosa pine forests, for example, could convert to chaparral fields. Oak woodlands could change to grassy savannas. (As California previously noted, such ecotonal changes already may be occurring on Mt. Laguna in Southern California.)
That all sounds pretty apocalyptic no matter how you burn it, but Thompson observes we don't have to just sit back and take it. It turns out there's quite a bit that could be done to fireproof our forests—and perhaps increase water availability in the process. All it will take is a fair amount of money and political will.
“It's clear that there is more standing biomass—trees—in our forests than existed before active fire suppression began a century or so ago,” says Thompson. “Studies show that the canopies are heavier, and the forests are more vulnerable to fire as a result.”
A little background: Prior to Euro-American settlement, California's coniferous forests were characterized by extremely large, widely-spaced trees. Annals of the day—both textual and pictorial— made it clear that you could ride a horse through the forests unimpeded. There was little or no fuel (branches and dead trees) on the ground. The character of the forests was due to the occurrence of fire, both natural and human-induced; California's natives burned the forests periodically to make hunting easier and encourage the growth of food plants, including acorn-bearing oaks, seed-producing grasses, and bulbs.
The good news: The forests of our forebears probably can be reclaimed. All we have to do is burn and cut down a lot of trees.
In the old days, fire noodled around in a low-energy fashion on the forest floors, killing insect pests, nibbling back the underbrush, and converting deadwood to ashes that ultimately nourished the great pines and firs. Today, wildfires rip through entire landscapes of closely-packed trees, immolating everything down to mineral earth.
“Ultimately, the fires can be so intense that they take out all tree seed sources,” says Thompson, “so the system shifts to chaparral.”
Today's dense forests also have less biodiversity and suck up much more water than the forests of yesteryear. Thompson says studies of today's Sierra Nevada forests indicate they transpire 35 percent more water—that is, extract it from the ground through the roots and transfer it to the air as vapor via foliage—than 19th Century forests.
The good news: The biologically rich, fire resilient and amply watered forests of our forebears probably can be reclaimed. All we have to do is burn and cut down a lot of trees.
“There are three ways to go about it,” says Thompson. “Mechanical thinning, prescribed fire, and managed fire.”
Mechanical thinning would be the removal of trees by chainsaws or heavy equipment. Prescribed fire would be controlled burning—setting blazes when fuels are relatively damp and conditions are cool and humid, allowing for fires that reduce the forest canopy without destroying every standing tree and living creature. Managed fire is basically letting nature run its course. Wildfires would be allowed to burn in unpopulated areas, ideally when weather conditions aren't excessively hot and dry. The U.S. Forest Service is increasingly convinced of the wisdom of this approach. It recently inaugurated new management plans for three of California's national forests, approving managed fire for 50 percent of their acreages.
Thompson and UC Berkeley professor of environmental science, policy and management Scott Stephens are working on a project in Illilouette Creek basin in Yosemite National Park that seems to confirm the healing properties of fire.
“The National Park Service backed off fire suppression and began using managed fire in the basin in 1973,” says Thompson. “Scott and I are seeing strong evidence for increased plant diversity in the basin. There's much more meadowland and scrubland, and the resulting patchiness across the landscape reduces the risk for catastrophic wildfire. We're also seeing greater diversity in water conditions. There are more areas with persistently wetter soils than were recorded under the old completely forested state. We're now trying to determine whether these changes are increasing run-off from Illilouette Creek into the Merced River. “
- Author: Glen Martin
Reposted from California Magazine
Back when mastodons and giant ground sloths still roamed the earth – the late 70s and early 80s – I worked as a wildfire fighter for the U.S. Forest Service, both on hand crews and engine crews. Our training was narrow but relatively deep. Mainly, we were taught to construct fire lines with hand tools and chain saws. Water, when it was available, generally was used to protect the line and firefighters; seldom was it employed to directly extinguish the flames.
Our basic strategy consisted of digging and cutting line around the flanks of the fire, then burning out fuels to the advancing flames with fusees (devices resembling highway flares) or drip torches. In this way, the “head” of the fire could be steered to natural barriers or areas sufficiently devoid of fuels to make a direct attack possible. We received zero training for structure firefighting. The one time I responded to a burning structure was in Trinity County: A vacation cabin was ablaze due to a faulty propane line. Several engines responded. Federal Forest Service engines are smaller and hold far less water than municipal or state engines, but collectively, we mustered a lot of water on the scene. A direct attack could have been possible, but we knew our training for battling such a fire was inadequate. Instead, we dug a line around the cabin so the flames wouldn't encroach into the surrounding woods, and watched it burn to the ground.
Things are different now. For one thing, wildfires are bigger and more frequent. This is due to drought, climate change, and the sins of past forest managers. In the sixties, seventies and eighties, vast tracts of old growth timber were liquidated in massive clear cuts. These deforested landscapes were replanted as conifer monocrops, resulting in expansive stands of spindly, closely-spaced, second-growth trees that are as flammable as kerosene.
Meanwhile, the goal for wildfire fighters has changed drastically. The emphasis now is on “protecting interface,” which means preventing fires from immolating the homes that have sprouted across the West's woodlands like morel mushrooms after a rain (back when we had rain). This shift has made fighting wildfires far more expensive, more dangerous for firefighters, and has altered priorities from protecting public forests to protecting private assets. Wildfire fighters now receive training in structure fires, but that has diluted, perhaps even vitiated, their original mission. As Berkeley Environmental Science Professor and Wildfire Researcher Scott Stephens noted, more than half the U.S. Forest Service budget for the current fiscal year is dedicated to fire suppression; in the early 1990s, that figure was about 20 percent. Assuming the trend will continue, which seems certain, firefighting could consume 70 percent of the agency's budget by the 2020s.
That means there's less money than ever for restorative work. And this is work that must be done, and soon. Unless we alter the essential characteristics of our coniferous forests, they will quite literally vanish. It's already happening: Stephens observes that significant portions of California's forests are shifting from pine and fir to mixed hardwoods or even grasslands, the result of repeated, high-intensity fires and drought. And once our conifers are gone, we're not getting them back. The change will be permanent.
Even with drought and accelerating climate change, we can still have healthy coniferous forests in the West. But we won't get them by simply letting them grow — and burn (and burn). Stephens observes we need active management: intensive thinning by both mechanical means and prescriptive fire. This will result in forests with fewer but healthier trees, forests that are largely resistant to any but the most catastrophic fires.
A hundred years ago, disastrous wildfires were rare in California. Forests were characterized by widely spaced, extremely large trees; You could ride through them on horseback, unimpeded. Any fires that did ignite generally crept along. They didn't have the “fuel ladders” — dead limbs and needles on the ground, brush and ascending foliage higher up — needed to climb into the crowns of the trees and explode into rolling fireballs. Being large, the trees were thick-barked and resistant to fire. Indeed, periodic low-level fires disposed of deadwood, killed destructive insects, and returned nutrients to the soil as ashes. It was a virtuous cycle, assuring healthy, resilient wild lands that depended on fires, but were not destroyed by them.
That changed with the aggressive fire suppression of the Smokey the Bear era and accelerated clear-cut logging. But as Stephens notes, we can revitalize the “dog hair” (as in, thick as the hair on a dog's back) forests we now have. We can re-create the vibrant, fire-resistant forests of the early 20th century. We know how to do it. We have the tools: chain saws, heavy equipment, and prescriptive fire. It's not that complicated.
But it will take political will and money. It won't require a Manhattan Project-style response —but it'll require one similar to the Civilian Conservation Corps in scope and commitment. We need to put young men and women back into the woods in force, cutting trees and conducting controlled burns. By re-introducing fire into forest ecosystems, we can, paradoxically, protect them from fire. This will entail triage. We'll have to identify those areas that are most vulnerable to fire (e.g., interface communities). The first projects should be shaded fuel breaks, strips of thinned forests around highways and rural towns and residential developments. Following that, more ambitious projects could proceed on larger tracts.
Who pays? The state and feds must contribute, of course. But local communities, commercial timber companies, and private landowners must also cough up. In particular, the counties and interface residents must participate. So far, they've gotten a free ride. County planners have encouraged development in wild-land areas without thought to the implications of wildfire; After all, taxpayers have always picked up fire suppression costs. More suppression costs must be passed on to the counties so they are incentivized to discourage development in our wild lands, and homeowners must pay appropriately heavy premiums if they choose to build in the woods.
Stephens estimates we have about 30 years before it's too — before our coniferous forests are gone forever, replaced with oak woodlands, brush fields, or grassy savannas. And even then, of course, the wildfires will continue. As we saw with the recent Middletown conflagration, hardwood forests and scrublands can burn just as ferociously as conifers. As long as homes intrude into the wild lands, their continued destruction is assured.
We can continue down the current path of increasing fires and escalating suppression costs, or we can invest in forest restoration. The first course is a death spiral. The second will reduce wildfires, preserve the essential character of our wild lands, provide tens of thousands of jobs to young Americans, yield economic benefits ranging from timber production to recreation, stabilize watersheds, and preserve wildlife diversity. Let's just hope we do the right thing.