A fuel ladder or ladder fuel is a firefighting term for live or dead vegetation that allows a fire to climb up from the landscape or forest floor into the tree canopy. [1] [2] Common ladder fuels include tall grasses, shrubs, and tree branches, both living and dead. The removal of fuel ladders is part of defensible space 'firescaping' practices.
Potential fuel ladders should be removed to reduce the risk of fire bridging the gap to the canopy. To remove the ladder requires pruning any low limbs up to a minimum of 8 feet, and potentially as high as 15 feet. The required height depends on how low the branch tips hang, the steepness of slope, and the height and spacing of other nearby vegetation.[ citation needed ]
The desired result is to create a situation in which a low-burning fire could burn to the trunk of a tree, which is protected by its bark, without having thinner, more flammable branches, leaves or needles within easy reach of the fire.[ citation needed ]
Apart from tree limbs, anything that would help that fire move up into the tree canopy is a fuel ladder. This includes shrubs and even tall grass or weeds. Non-vegetation fuel sources such as woodpiles, wooden fenceposts and structures should also be considered.[ citation needed ]
The intent is to maintain a break in vertical and horizontal continuity so that, if for example a woodpile caught fire, it would not be positioned next to shrubs or directly under trees that could then easily catch fire.[ citation needed ]
A savanna or savannah is a mixed woodland-grassland ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of grasses. According to Britannica, there exists four savanna forms; savanna woodland where trees and shrubs form a light canopy, tree savanna with scattered trees and shrubs, shrub savanna with distributed shrubs, and grass savanna where trees and shrubs are mostly nonexistent.
Rangelands are grasslands, shrublands, woodlands, wetlands, and deserts that are grazed by domestic livestock or wild animals. Types of rangelands include tallgrass and shortgrass prairies, desert grasslands and shrublands, woodlands, savannas, chaparrals, steppes, and tundras. Rangelands do not include forests lacking grazable understory vegetation, barren desert, farmland, or land covered by solid rock, concrete and/or glaciers.
A firebreak or double track is a gap in vegetation or other combustible material that acts as a barrier to slow or stop the progress of a bushfire or wildfire. A firebreak may occur naturally where there is a lack of vegetation or "fuel", such as a river, lake or canyon. Firebreaks may also be man-made, and many of these also serve as roads, such as a logging road, four-wheel drive trail, secondary road, or a highway.
Abies concolor, the white fir or Colorado fir, is a coniferous tree in the pine family Pinaceae. This tree is native to the mountains of western North America, including the Cascade Range and southern Rocky Mountains, and into the isolated mountain ranges of southern Arizona, New Mexico, and Northern Mexico. It naturally occurs at elevations between 900 and 3,400 metres.
This glossary of wildfire terms is a list of definitions of terms and concepts relevant to wildfires and wildland firefighting. Except where noted, terms have largely been sourced from a 1998 Fireline Handbook transcribed for a Conflict 21 counter-terrorism studies website by the Air National Guard.
Limbing or delimbing is the process of removing branches from a standing or fallen tree trunk.
Secondary succession is the secondary ecological succession of a plant's life. As opposed to the first, primary succession, secondary succession is a process started by an event that reduces an already established ecosystem to a smaller population of species, and as such secondary succession occurs on preexisting soil whereas primary succession usually occurs in a place lacking soil. Many factors can affect secondary succession, such as trophic interaction, initial composition, and competition-colonization trade-offs. The factors that control the increase in abundance of a species during succession may be determined mainly by seed production and dispersal, micro climate; landscape structure ; bulk density, pH, and soil texture.
A Fuel Model is a stylized set of fuel bed characteristics used as input for a variety of wildfire modeling applications. Wildfire behavior models, such as those of Rothermel, take into account numerous empirical variables. While these inputs are important for equation outputs, they are often difficult and time-consuming, if not impossible, to measure for each fuel bed. A fuel model defines these input variables for a stylized set of quantitative vegetation characteristics that can be visually identified in the field. Depending on local conditions, one of several fuel models may be appropriate. As Anderson states “Fuel models are simply tools to help the user realistically estimate fire behavior. The user must maintain a flexible frame of mind and an adaptive method of operating to totally utilize these aids". Furthermore, depending on the application, the user must choose a fuel model classification system. The major classification systems for use in the United States include the National Fire Danger Rating System, the 13 ‘original’ fuel models of Anderson and Albini, the subsequent set of 40 fuels produced by Scott and Burgan, and the Fuel Characteristics Classification System.
Fire safe councils are grassroots community-based organizations in California that share the objective of making communities less vulnerable to catastrophic wildfire. Fire safe councils accomplish this objective through education programs and projects such as shaded fuel breaks or firebreaks to protect area residents against an oncoming wildfire and to provide firefighters with a place to fight the oncoming fire. The first fire safe councils started in the early 1990s, and there are now over 100 around the state.
A defensible space, in the context of fire control, is a natural and/or landscaped area around a structure that has been maintained and designed to reduce fire danger. The practice is sometimes called firescaping. "Defensible space" is also used in the context of wildfires, especially in the wildland-urban interface (WUI). This defensible space reduces the risk that fire will spread from one area to another, or to a structure, and provides firefighters access and a safer area from which to defend a threatened area. Firefighters sometimes do not attempt to protect structures without adequate defensible space, as it is less safe and less likely to succeed.
The 2009 California wildfires were a series of 9,159 wildfires that were active in the US state of California, during the year 2009. The fires burned more than 422,147 acres of land from early February through late November, due to Red Flag conditions, destroying hundreds of structures, injuring 134 people, and killing four. The wildfires also caused at least US$134.48 million in damage. Although the fires burned many different regions of California in August, the month was especially notable for several very large fires which burned in Southern California, despite being outside of the normal fire season for that region.
A fire-adapted community is defined by the United States Forest Service as "a knowledgeable and engaged community in which the awareness and actions of residents regarding infrastructure, buildings, landscaping, and the surrounding ecosystem lessens the need for extensive protection actions and enables the community to safely accept fire as a part of the surrounding landscape."
Wildfires are outdoor fires that occur in the wilderness or other vast spaces. Other common names associated with wildfires are brushfire and forest fire. Since wildfires can occur anywhere on the planet, except for Antarctica, they pose a threat to civilizations and wildlife alike. In terms of emergency management, wildfires can be particularly devastating. Given their ability to destroy large areas of entire ecosystems, there must be a contingency plan in effect to be as prepared as possible in case of a wildfire and to be adequately prepared to handle the aftermath of one as well.
Dry sclerophyll forests occur throughout northern and eastern Tasmania. Characterised by the population of hard-leafed (sclerophyll) and often spiky, drought-adapted plants, dry sclerophyll forests are found in regions of where annual rainfall is below 1000mm.
Forestry mulching is a land clearing method that uses a single machine to cut, grind, and clear vegetation.
The relationships between fire, vegetation, and climate create what is known as a fire regime. Within a fire regime, fire ecologists study the relationship between diverse ecosystems and fire; not only how fire affects vegetation, but also how vegetation affects the behavior of fire. The study of neighboring vegetation types that may be highly flammable and less flammable has provided insight into how these vegetation types can exist side by side, and are maintained by the presence or absence of fire events. Ecologists have studied these boundaries between different vegetation types, such as a closed canopy forest and a grassland, and hypothesized about how climate and soil fertility create these boundaries in vegetation types. Research in the field of pyrogeography shows how fire also plays an important role in the maintenance of dominant vegetation types, and how different vegetation types with distinct relationships to fire can exist side by side in the same climate conditions. These relationships can be described in conceptual models called fire–vegetation feedbacks, and alternative stable states.
The SCU Lightning Complex fires were wildfires that burned in the Diablo Range in California in August and September 2020 as part of the 2020 California wildfire season. The fire complex consisted of fires in Santa Clara, Alameda, Contra Costa, San Joaquin, Merced, and Stanislaus counties. The name is derived from the three-letter designation given to the California Department of Forestry and Fire Protection division responsible for the Santa Clara, Alameda, Contra Costa, and parts of San Joaquin and Stanislaus counties, and the complex consisted of several distinct fires occurring in this region.
The 2020 Dome Fire was a large and ecologically destructive wildfire in the Mojave National Preserve in California's San Bernardino County. Caused by a lightning strike on August 15, the fire began near Cima Dome and exhibited rapid growth over the following 36 hours, aided by weather conditions and a lack of available firefighting resources. During this period the Dome Fire destroyed only 6 structures, but burned more than a quarter of the Cima Dome Joshua tree forest, one of the largest and densest populations of Joshua trees known in the world. The fire killed as many as 1.3 million Joshua trees. No injuries or fatalities were reported among firefighters or civilians. The fire cost US$2.2 million to suppress, and burned 43,273 acres (17,512 ha) before being fully contained on August 24.
The 2023 California wildfire season is a series of wildfires burning in the U.S. state of California. As of July 26, 2023, a total of 3,619 fires have burned a total of 22,325 acres. No wildfire fatalities have been recorded. The 2023 fire season follows the 2022 season, in which a below-average number of fires burned an also-below-average acreage, owing in part to weather patterns.
Cultural burning is the process of using prescribed burns to manage landscapes, a process used primarily by the first peoples. More specifically the Indigenous people of Australia and the Western parts of North America have been found to use this method extensively. This practice created a relationship between the land and the people so strong that the local flora became dependent on patterned burnings. The practice then elevated the Indigenous peoples of their respected environments to a keystone species status as the interspecies connections strengthened over time. Which is partially why Indigenous people still manage 40-60% of all ecological reserves.
