In over 40 years working at the California Department of Forestry and Fire Protection, Mike Martin, now Alameda County battalion chief, has never seen anything like October 20, 1991 in the hills east of Oakland and Berkeley. “Extreme fire conditions, high-velocity wind,” Martin recalls. The 20 to 30 miles per hour winds, with gusts of up to 40, blew west through narrow East Bay canyons stricken by drought and a heavy frost the previous winter that killed thousands of non-native trees.
The fire’s speed and energy during that first hour, when it destroyed 790 homes, is what killed most of the people—trapped in their homes or cars, where smoke and fire overcame them before they could escape. Twenty-five people died that day in the Tunnel Fire, what later became known as the Oakland Hills Firestorm. The fire injured 163 others, destroyed about 3,400 homes and cost over $1.5 billion in damages.
Although the fire was the most destructive to ever hit the East Bay, it wasn’t the first and it wasn’t the last—and it could have been much worse. The Claremont and Temescal Canyons have high amounts of flammable plants; lots of people, homes and cars on the edge of the wildlands; and steep slopes, combined with seasonal dry Diablo winds—the Bay Area’s variant of the infamous Santa Anas of Southern California. “The reasons why the 1991 could not be stopped,” according to a 2001 report prepared for East Bay Regional Parks in 2001, “still exist today in many locations throughout the East Bay hills.”
This March, the Federal Emergency Management Agency (FEMA) announced their final decision to award $5.6 million to a coalition of East Bay agencies to reduce wildfire risk. The grant comes nearly 24 years after the Oakland Hills Fire, and ten years and 13,000 public comments after the parks agency and nearby cities applied for it. The money would be used to cut down blue gum eucalyptus, along with smaller amounts of Monterey pine and acacia, in and around Claremont Canyon. After the trees come down, the plan is to help less flammable—and mostly native—plants gain a foothold in their place.
The Claremont Canyon Conservancy, a nonprofit group of about 500 homeowners formed after the 1991 fire, strongly supports the plan. “People can deny that eucalyptus are fire dangers, but actually they’re about as fire dangerous as a plant material can get,” says Marilyn Goldhaber, a founding board member of the conservancy, which is focused on wildland restoration and wildfire protection.
Goldhaber’s conservancy coordinates closely with the Hills Emergency Forum, a broad coalition of public agencies and organizations that helped to craft the FEMA grant and supports it. The forum includes Martin’s Cal Fire, along with the cities of Oakland, Berkeley, and El Cerrito; East Bay Regional Parks; University of California, Berkeley and Lawrence Berkeley National Laboratory; and East Bay Municipal Utilities District. The Sierra Club, after objecting that the FEMA plan did not go far enough, joined Goldhaber’s Claremont Canyon Conservancy in supporting the project.
But the very next day after the FEMA grant was announced, a tiny nonprofit called the Hills Conservation Network, also based in Claremont Canyon, filed a lawsuit in opposition. According to the group, the plan greatly overestimates the flammability of eucalyptus, and “FEMA did not consider a reasonable range of alternatives.”
“We shouldn’t even be talking about eucalyptus trees,” says Dan Grassetti, founder of the group. “We should be talking about wildfire risk mitigation. That’s what the grant is for. It’s not for native plant restoration.”
Bob Maloney, a retired firefighter and former fire chief for Oakland Navy Yard, is a member of Grassetti’s Hills Conservation Network. He criticizes the FEMA plan in blunt terms. “It’s just amazing to me how we have people in positions of authority who have no credentials in wildland fire prevention, no credentials in fighting fires … making policy,” Maloney said at a recent gathering of supporters at the Oakland Spiritual Center. “What bothers me is there aren’t any reporters asking these people.”
The two organizations with similar-sounding names have very different ideas for reducing wildfire risk in Claremont Canyon. Will cutting down and replacing the eucalyptus really reduce the risk of another disaster like the 1991 firestorm? And will the herbicides used to prevent the eucalyptus from growing back do long-term damage to the Oakland hills ecosystem?
In order to understand why eucalyptus trees have become so controversial, you need to know a little natural history.
According to fire ecologist Jon Keeley, it is hard to say what landscape in the East Bay hills would be most “natural.” Native Americans changed much of the hills from forest and shrubland to grassland with controlled burning. Europeans brought sheep and cattle, which grazed on the grasslands. But as more people settled the steep hills with spectacular views, grazing animals gradually disappeared and shrubland began replacing grassland.
In the early 20th Century, progressive real estate developer Frank Havens planted millions of eucalyptus in the East Bay hills, both for hardwood lumber and to make the hills more scenic for the homes he built. Havens’ plan, however, went seriously awry: The California eucalyptus made poor lumber, but it grew fast and crowded out native plants. That is because the alleopathic effect it creates alters nearby soil’s chemical composition to the tree’s own benefit, but to the detriment of native plants. And eucalyptus, it turns out, had a major unintended consequence—one that has to do with an unusual weather anomaly of the East Bay hills called Diablo winds.
In the fall, Diablos sometimes kick up, blowing hot dry air west—and Gwin Canyon, a box canyon within Claremont Canyon, forms the lowest, narrowest opening in the East Bay Hills. When the Diablos blow through, they accelerate like a wind tunnel through Gwin, Claremont and Temescal Canyons, an effect that can transform a small grassfire into a raging firestorm within minutes.
Since 1923, nearly 20 major wildfires have burned through the East Bay Hills, including at least eight driven by Diablos—the most destructive ones. The 1923 Berkeley fire reportedly started in eucalyptus north of the Cal campus. Fanned by Diablos, it burned into the city along a 1,600-foot front. Within about two hours, it destroyed 584 buildings, burned to the edge of campus, and left 4,000 people homeless.
In 1970, during a bad fire season, another Diablo-driven wildfire started near Fish Ranch Road and razed 37 homes. Firefighters who quickly doused the flames warned that it could have been much worse.
On October 19, 1991 a small grass fire started in almost exactly the same spot as the 1970 burn, near the intersection of Grizzly Peak Road and Marlborough Terrace. What happened the next day did turn out to be much, much worse.
California was suffering through the midst of a years-long drought in 1991 and another bad fire season while recovering from a recession that deeply cut fire department budgets. In the winter of 1990, a deep frost killed thousands of eucalyptus trees in the East Bay Hills, and by October they had dried out and formed a tinderbox.
Fire crews quickly got the grass fire under control, but not out, and were still raking and hosing embers when night fell. Fires burning near Alamo and throughout California had stretched local crews thin. As a fire crew returned to work over embers early the next morning, along came the dreaded Diablos they’d been fearing.
Javier Trelles and Patrick J. Pagni, fire scientists at UC Berkeley, wrote about what happened next in their own report, for the National Institute of Standards and Technology (NIST).
“The initial brand material came primarily from Monterey pine, Pinus radiate,” they wrote, describing a tree that is also non-native to the East Bay, but native to the California Coast south of the Bay Area. “About 650 meters from the fire origin, the fire engaged a 35-meter high stand of Eucalyptus globulus [blue-gum eucalyptus] that quickly became an inferno releasing copious brands. Once structures became involved, the shakes and shingles they liberated further exacerbated the flaming brand problem.”
The 1991 fire burned the exact same properties destroyed in 1970 within minutes. Driven by Diablos and creating its own convection winds, the firestorm crossed Highways 24 and 13. Hundreds of water lines ruptured, power lines arced from the heat, then failed. Thousands of residents fled Hiller Highlands and Parkside Terrace, sometimes moments before their homes burned to the ground. Eleven people died in their cars while fleeing down narrow Charing Cross Road as fire trucks tried to race up in a futile effort to stop the flames. Eight others died nearby—all in the first hour, when the flames spread faster than any fire anyone had ever seen. Police and fire crews became evacuators—and two of them lay among the victims. Surrounded on Tunnel Road, a fire crew herded trapped residents into the concrete garage of a home, then hosed water on the home as the flames raced by. All of them survived.
Reservoirs ran dry as hoses and helicopters emptied them. Overwhelmed firefighters made a desperate stand east of the Claremont Hotel, fearing that if the massive wood building caught fire, the flaming embers would doom the entire city of Berkeley. As the wind shifted from blowing west to south, the Diablos carried flying embers over fire lines, over Lake Temescal, and into Rock Ridge toward Piedmont.
According to the FEMA report, “The fire completely overwhelmed the firefighting forces of the area, consuming everything in its path, and was only stopped when the Diablo wind conditions abated. The wind had threatened to drive the fire across the entire city of Oakland.”
Then, as evening fell, the wind stopped. Offshore breezes wafted in, cooling the fire and turning it back on itself-onto already razed neighborhoods. Starved of fuel, firefighting reinforcements got the flames under control early the next day. In less than six hours, a few embers had turned into the deadliest and most destructive wildfire in California history.
The FEMA report devotes five pages to describing the “extreme fuel loading” that the eucalyptus and drought caused. Pagni also implicated eucalyptus in the NIST report, as well as his peer-reviewed scientific paper, “Causes of the 20 October 1991 Oakland Hills Conflagration.” Fire ecologist David Bowman of the University of Tasmania, where blue-gum eucalyptus originate, says the same thing. In other words, NIST and FEMA as well as numerous scientists all agreed that eucalyptus played a significant role in making the 1991 fire so destructive.
These findings, however, were nothing new. As A 1973 study published in California Agriculture stated, “Results of this study indicate that fuel buildup occurs very rapidly in unmanaged eucalyptus stands.”
“A lot of the eucalyptus trees [are filled] with stripped bark and dead fuel,” Cal Fire’s Mike Martin says, “not only on ground but stuck up in the trees,” The bark is “much more aerodynamic,” he says, compared to a stick or pine cone, for example, because it’s long and flat and can gain lift like the wing of an aircraft. In high winds, like on that October Sunday, they can start spot fires hundreds of yards away from the main flames.
Marilyn Goldhaber, a former epidemiologist, lives across Claremont Canyon from Grassetti in the Berkeley Hills. “The Conservancy started as a group of neighbors who were very concerned after the big fire in 1991,” Goldhaber says. “Some of us even lost our homes.”
The 1991 fire stopped about a block from Goldhaber’s hillside home.
The conservancy has held about three workdays per month since its founding, during which they clear brush and do wildfire protection. As she hikes through the same eucalyptus grove that sits below Dan Grassetti’s balcony, Goldhaber says that the base of these eucalyptus trees are are a bonfire waiting to happen. Crunching through the eucalyptus detritus wearing hiking boots and a ponytail, Goldhaber pulls off strips of bone-dry bark that collect along with branches in piles at the base of the trees, some taller than she is. The entire grove is covered with this dry, crunchy kindling and tinder.
“Eucalyptus often forms the perfect fire ladder,” Goldhaber says, peeling the bone-dry bark and grabbing sticks piling up. She snaps them in her workglove-covered hands with a sharp crack. “It can climb up the bark, and the eucalyptus bark forms perfect kindling,” she says. “It can rush across the canopy at very high speed, very hot, and send embers flying sometimes several miles away.”
Eucalyptus grows fast, and its bark and leaves create thick, flammable duff that burns twice as hot as a grassland fire. Oil in dried leaves slows their decomposition and burns explosively. Tall and hard to put out, and limbs tend to break easily and unexpectedly when on fire, risking lives and spreading fire.
Eucalyptus grows in dense stands—up to 900 trees per acre, compared to 30 to 50 trees per acre on average for some other tree species. And grassland creates about one ton per acre of flammable fuel, according to Cal Fire’s Mike Martin. Eucalyptus creates twenty to fifty times that.
”We’re not completely safe when we take the eucalyptus down,” Goldhaber says, “but the eucalyptus pose a particularly high risk.”
The FEMA plan is also meant to allow native species with lower fire risk to grow back after the larger trees are removed. “Under the FEMA grants program, eucalyptus and pine trees will be removed and the land converted to a less fire-prone condition,” according to the Conservancy website. “In any case it will not remain bare for any extended period. Native trees, scrub and grasses grow rapidly when eucalyptus are removed.”
But the Hills Conservation Network’s Dan Grassetti, who is spearheading the lawsuit with Oakland law firm Lozeau Drury sees the FEMA plan as wrongheaded interference with nature. “Trees had very little to do with the fire,” Grassetti says from his backyard balcony overlooking spectacular Claremont Canyon. He bought his house in 1992, right after the firestorm, which burned within four houses of the property.“Trees were incidental.”
He says cutting eucalyptus will lead to more grass, which burns faster and, he says, is more dangerous than eucalyptus. “I recognize that it’s a choice to live in a wildland-urban interface,” Grassetti says, “and when you make that choice you accept some risks. For me, the rewards more than outweigh the risks.”
Grassetti says that while sitting on the wooden balcony of his beautiful home, covered in wood-shingles and wood siding, with oak tree branches pushing up against the wood railing and the walls—none of which Cal Fire recommends for homes in the wildland-urban interface.
“Their real agenda is native plant restoration rather than fire hazard mitigation,” Grasetti says of FEMA and the other agencies that support the cutting plan. But he says that his Hills Conservation Network is “species-neutral.”
“I don’t think we’re talking about the right thing,” Grassetti continues. “It would be better to talk about fire risk mitigation,” like having more firefighters nearby and more aircraft and helicopters to attack the fires from the air.
Grassetti’s Hills Conservation Network colleagues, in addition to former Oakland firefighter Dave Maloney, include artist Jack Gescheidt and Peter Scott, who lost his mother in the ’91 fire. They don’t believe that cutting mature trees is a smart plan to reduce fire danger. And most fire ecologists agree—in most cases. When it comes to managing wildlands to manage fire, cutting mature trees is usually the last thing people want to do, and “thinning” and “salvage logging” have often been used as pretexts to log big trees under the guise of fire protection.
Martin and Goldhaber point out, however, that eucalyptus are different than most trees. And the Diablos make the East Bay Hills different than most wildlands.
Grassetti’s Hills Conservation Network also don’t like that the FEMA plan calls for herbicide use. Because eucalyptus drops thousands of seeds, and re-sprouts all around a cut stump, FEMA recommends the use of small amounts of herbicide to prevent their re-growth long enough for native plants to re-establish themselves.
Garlon 4 and Garlon 3A will be used on eucalyptus stumps, according to the FEMA documents, applied with a brush to keep them from growing back. RoundUp will used to prevent recolonization by French broom until native plants establish themselves. RoundUp is made by Monsanto, an agribusiness corporation controversial for its production of products like DDT, Agent Orange and bovine growth hormone. Some of Monsanto’s products have also been lifesavers, however—used to treat diseases like Parkinson’s and to increase crop yields around the world. The company is so controversial that Bay Area favorite Neil Young even has an underground concept album called “Monsanto Years.”
“We’re shocked,” says Grassetti, “[that] the Sierra Club would sue to kill close to half a million trees and douse the hills with ten years of toxic herbicies to prevent regrowth.”
But according to scientific reports, Garlon (aka Triclopyr) appears to be nontoxic in the quantities proposed. RoundUp is listed as a probable human carcinogen—in large quantities—in Europe, but no such conclusion has been reached in the US. And the Claremont Canyon Conservancy believes it will be safe to use according to the plan. “Herbicide,” according to the group’s website, “will be used in such small quantities and under such strict controls that it will not be a carcinogen.”
Goldhaber is quick to point out that the Claremont Canyon Conservancy does not use herbicides during its workdays. “But we understand that it has to be used in this situation,” she says. “I think being afraid of the herbicide is not a reasonable point of view.”
And as Goldhaber points, out the more the weeds get pulled, the less herbicide would be needed in the years after the eucalyptus gets cut down—and as less eucalyptus grows back. Goldhaber points to the conservancy’s track record with pride. “You have to be almost a fanatic, which some of us are at the conservancy. We will pull that [French} broom regularly.”
“I’m dying to pull those,” she says with a laugh, pointing toward some eucalyptus saplings.
Plus, she says, the relative risks of herbicide are small compared to the worst-case scenario of another Oakland fire. “It could burn down,” she says simply.
Compared to 1991, Cal Fire’s Mike Martin says, the Oakland Hills have better wildfire protections. Buildings have become far more fire-resistant. Water systems have improved greatly, aided by better pumps and a new fire station in the hills. Road access for fire trucks and evacuation have improved just slightly—it’s tough to do more because of the slopes and private property. Communications have improved significantly with digital technology. But water, roads and communications all remain at risk of being overwhelmed during another fire emergency.
Fuel load, according to Martin, is slightly better, but “Drought is killing us on fuel load” by drying out grasses, shrubs, and even trees. And while the dreaded Diablo winds remain the greatest risk factor for wildfire in the East Bay hills, eucalyptus remain a major fuel source. And unlike the Diablos, Martin and Goldhaber say, something can be done about the eucalyptus. “With the conditions we have in the East Bay hills,” Martin says, “eucalyptus are a really big fire risk. We’re not saying eucalyptus is the only factor, but they are a big factor.”
With climate change underway, more extreme weather patterns are likely to become the norm: wetter years, drier ones, longer hot spells, perhaps more frequent deep frosts that kill eucalyptus trees. Right now, the East Bay hills have more people, drier fuel, and less water than at any time in recorded history. That makes the eucalyptus question an urgent one.
Correction: An earlier version of this story stated that FEMA awarded $5.6 million to the East Bay Regional Parks District. Although the parks district is a lead agency administering the land, the money also went to UC Berkeley and the city of Oakland, among other local agencies.