Posts Tagged: wildfire
Clearing vegetation helps protect homes from fire
Clearing vegetation close to houses is the best way to reduce impacts of severe wildfires, according to a team of scientists from Australia and the U.S., said an article published in Science Codex. The researchers examined house loss after a series of fires raged across the Australian state of Victoria in February 2009, killing 173 and injuring 414.
However, fuel reduction close to houses is only a partial solution. Other measures - such as early evacuation, safer places and architectural solutions - should also be considered by residents in fire-prone areas.
"These are findings that are probably important internationally," said Max Moritz, UC Cooperative Extension specialist at UC Berkeley, a co-author of the research.
Oakland Hills fire prompted changes in building laws
Fighting the wildfire was hampered by steep and narrow roads, houses with wood-shingle roofs, a restricted water supply, and fire hydrants that were incompatible with neighboring cities’ trucks. The wildfire, which burned for almost 72 hours, took 25 lives, devastated over a thousand acres of land, and destroyed more than 3,500 homes.
Oakland now requires all new Oakland Hills houses to have fire-resistant roofs, which include slate, clay, concrete roof tile or steel shingles, according to the Builders Wildfire Mitigation Guide, published by the UC Division of Agriculture and Natural Resources.
“These materials are more accessible now than in 1991,” said Steve Quarles, a researcher at the Insurance Institute for Business and Home Safety, a Florida-based organization that conducts studies on natural disasters aimed to reduce human and financial loss. Quarles retired from UC Cooperative Extension Aug. 1 after serving for 26 years as a wood durability advisor. “Probably most of them were available at that time, but now they are less expensive and people can acquire more information about them.”
How to decipher nutrition labels
Claudia Mosby, The Redding Record-Searchlight
A heart-healthy, sugar-free or low-fat label on your favorite box of crackers at the store doesn't automatically mean it's a healthy food item. These eye-catching labels draw attention to what may be a healthier choice, but to accurately assess the item's nutritional value you need to read and understand its nutrition facts label.
According to Concepcion Mendoza, nutrition family and consumer science advisor at University of California Cooperative Extension in Shasta and Trinity counties, nutrition facts labels became mandatory in the early 1990s. These labels list the number of calories, fat grams and nutrients per serving for a food item, along with its percent of daily value recommendation.
U.S. Forest Service and UC study ways to reduce wildfire severity
The University of California Cooperative Extension (UCCE) recently co-hosted a field trip with the U.S. Forest Service to view the implementation of a forest fuels reduction project on the Tahoe National Forest.
Over 45 stakeholders, including representatives of state, federal, and local government, industry and environmental groups and local residents attended to see the project, known as the "Last Chance Project," which involves thinning the forest by removing small and medium-sized trees, masticating or mowing down brush, and burning dead material through prescribed fire. The work, being done by Sierra Pacific Industries, under contract to the U.S. Forest Service, should be completed by fall 2012.
University of California scientists and UCCE have teamed up with the U.S. Forest Service to provide independent third-party research on the project to determine its effects on forest health, fire behavior, wildlife, water quality and the public through the Sierra Nevada Adaptive Management Project (SNAMP).
The forest research team including Brandon M. Collins, now employed by the U.S. Forest Service Pacific Southwest Research Station as a research fire ecologist, collected data before the Last Chance project began to determine its likely effectiveness at improving the health of trees and reducing the potential for destructive high intensity wildfire. Collins led the effort to use computer models to determine how the Last Chance project, as proposed, will affect fire behavior across the surrounding landscape up to 30 years after completion. Additionally, other hypothetical treatments limiting the diameter of trees removed to different sizes were modeled to assess how effective the project will be at reducing fire severity.
The team sampled 199 forest plots and collected data, such as tree species, vigor, and diameter at breast height (dbh). Tree core samples were collected so the growth of tree rings can be determined to characterize tree productivity at each plot. Downed material, including branches, twigs, pine needles and decomposed organic material, were measured along with woody shrubs. Fuel loads were calculated using standard protocols.
This data was then entered into the Forest Vegetation Simulator (FVS) with the Fire and Fuels Extension to model the planned treatments and grow forest stands within the study area for several decades. Using a command line version of FlamMap, called Randig, and weather information from the Duncan Peak Remote Automated Weather Station, scientists simulated 5,000 randomly placed fire ignitions to model conditional burn probabilities, which are the chance occurrences of a pixel burning given an ignition within the study area under modeled weather conditions.
Results from that modeling show that fuels treatments as planned for the Last Chance project will be effective at reducing fire behavior not only within treated areas, but also in adjacent areas. Differences in modeled fire behavior, when different limits on the diameter of trees removed were modeled, were slight. This suggests that the key to effective reductions in the probability of more hazardous fire occurrence at the landscape scale is treating surface fuels and thinning ladder fuels, and that the diameter of the trees removed is less important.
Changes in design of fuels treatments project often occur during implementation when unexpected conditions occur. Therefore, post-treatment forest plot data will be collected again beginning in Fall 2012 to better characterize the treatment as implemented, and to re-examine the effectiveness of the modeling results.
Information for this article comes from: Collins, Brandon M., Scott L. Stephens, Gary B. Roller and John J. Battles. 2010. Simulating Fire and Forest Dynamics for a Landscape Fuel Treatment Project in the Sierra Nevada. Forest Science 57(2) 2011.
Photos by Shufei Lei, SNAMP
Photos by Shufei Lei, SNAMP
Solve economy, wildfires woes at same time
Forest restoration would be one way to improve our economy, writes researcher Tong Wu of the Center for Forestry and UC Berkeley on CNN's Global Public Square news website. He states that human interference has "made many ecosystems unnaturally susceptible to catastrophic wildfires" and that global warming will exacerbate the problem.
"In economic analyses of environmental management projects across the western United States, ecological restoration produced multiplier effects (the economic 'bang for the buck' of every dollar spent) that were higher than the estimated impacts of the 2009 government stimulus," he wrote.
It only takes a spark
The Las Conchas fire that recently consumed nearly 137,000 acres in Los Alamos, N.M., serves as a reminder of how quickly fire can move if given fuel. I can’t light a barbecue with matches and lighter fluid, but a small ember drifting on the wind can find so many ways to burn down people’s homes if given the right conditions.
Removal of vegetation near Los Alamos National Laboratory, which is part of the UC system, created a buffer and helped spare the lab from the Las Conchas fire, which came within 50 feet. Creating a buffer is one of many preventive measures that can be taken to protect property from wildfires.
In a wildfire-prone area, even if you have a house with a concrete tile roof and noncombustible siding, an ember landing on landscape mulch, igniting plants around the home or floating into a vent on the house or under decks may set the house ablaze, warns a UC Cooperative Extension fire expert.
“From years of observing the aftermath of fires and testing fire-resistant building materials, we have developed a much better understanding about what happens,” says Steve Quarles, UC Cooperative Extension wood performance and durability advisor.
Quarles lists six priority areas for evaluating the vulnerability of homes in fire hazard zones: the roof, vents, landscape plants, windows, decking and siding. For details on how you can reduce the threat of wildfire to your home, visit Quarles' Homeowner's Wildfire Mitigation Guide.
“We know that the zone within about five feet of the home is very important to home survival during a wildfire,” Quarles says.
Landscape mulch provides many benefits to a garden, but Quarles and his colleague Ed Smith, University of Nevada Cooperative Extension natural resource specialist, found that many types of mulch are capable of catching fire and burning. Within five feet of a house, they recommend placing only rock, pavers, brick chips or well-irrigated, low-combustible plants such as lawn or flowers.
Quarles and Smith have published a new manual comparing the relative susceptibility of eight mulch treatments to igniting and burning. To download a free copy of “The Combustibility of Landscape Mulches,” visit the UC Fire Center website.
The scientists tested eight types of landscape mulches, shown in this test plot.