Anatomy of a fire response: How USFS wildland firefighters tackle wildfires

By Robert Doucette, Shasta-Trinity National Forest, Public Affairs Office

When a pillar of smoke rises above the treetops, certain images come to mind about what happens next. 

Fire engines race to the scene, and firefighters get to work dousing the flames. The bigger the fire, the bigger the response. 

But a lot goes into how U.S. Forest Service firefighters respond to wildfire, much of which the public might not see. The planning, tactics and resources deployed to fight wildfires is a complex and ever-changing battle. 

So, what goes into fighting wildland fires? The following is a breakdown of how wildfires are fought, from beginning to end. 

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Initial response

The response begins once a fire is spotted. Sometimes this happens when a lookout sees smoke from their tower. Other times, satellite imagery can detect a blaze, or perhaps one of the many mountaintop cameras installed in the forest. Or it could be someone from the public who calls it in. Dispatchers will then notify the appropriate agency, be it the Forest Service or another agency. 

From there, resources – a term used to describe personnel, equipment, vehicles and aircraft – will be assembled. The size and makeup of this group will depend on factors associated with how high the fire hazard is. Weather, terrain, the size of the fire and what sort of fuels – the term used to describe live and dead vegetation that can burn – are all factors in determining the hazard level of a fire. 

The higher the hazard, the more resources are called up. This could be as small as a single fire engine and its crew. But if the hazards are greater, then multiple engines, aircraft and specialized firefighting crews – overland firefighters called hotshots, helitack crews that rappel out of helicopters to a fire, or skydiving firefighters known as smoke jumpers – can be assembled and deployed. 

If a fire is verified, the supervisor of the first crew on the scene becomes the incident commander. Multiple resources are automatically ordered. The incident commander will determine how big the response should be: either to handle it with the crew on hand and cancel the other resources or bring in more people, engines and equipment. 

The fire will then be named, usually after a nearby geographical feature. 

After the incident commander sizes up the situation and reports on what resources will be needed, dispatchers will redistribute other available assets to make sure the rest of the area is covered in case another fire breaks out. 

Firefighters first to arrive attack the fire as directly as possible. They’ll get as close to the fire as they can, establish an anchor point – a relatively safe spot to base their operations in an area that is unlikely to burn – and keep the fire as small as possible until it’s extinguished. 

“If it’s an emerging event, which means cascading in size, a couple things will happen,” said Todd Mack, Fire Management Officer for the Shasta-Trinity National Forest. “The on-scene incident commander will request appropriate resources they think they’ll need.” 

“For us to be successful in initial attack we prepare through intensive pre-planning which helps establish priorities and leads to quick and effective decisions,” added Nick Bunch, Acting Fire Management Officer for the Six Rivers National Forest. 

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Resources that fight fire 

Fire behavior, weather, fuel load and slope steepness all play a role into what tactics are used to fight the fire, and what resources are deployed. Other considerations include protecting lives and property, as well as firefighter safety. 

Engine crews pump water from tanker trucks to douse flames. Firefighters use hand tools to dig containments lines and create safe zones from which they operate. If things go well, an engine crew can extinguish a fire before it grows into something bigger. 

In incidents where the terrain leading to the fire is too steep or too far for hoses to reach, hotshot crews hike to the scene. In places where the terrain and forest conditions are too dangerous, or when a fire is burning too hot to approach, aircraft can be used to douse the flames with water or pour fire retardant in the area. 

And if the fire is too deep into a forest to be quickly reached by hotshot crews, helicopters can insert firefighters and smoke jumpers can parachute closer to a fire and begin tackling the blaze. 

“Fighting fire takes a variety of resources and specialties; no two fires are the same,” Bunch said. “The unique nature of each fire determines the specific resources need to effectively engage in firefighting efforts.”

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Prolonged fire response 

If it’s not possible to extinguish the fire in the initial response, firefighters will go into an extended attack – prolonged action to fight, contain and extinguish the fire. This will involve more resources, and resource rotation comes into play so firefighters can recuperate and return to action fresh. 

A direct attack will see firefighters directly approach the fire to put it out. But if the fire is too dangerous for a direct attack, an indirect attack posture is adopted. 

“What causes us to go into indirect is topography – it’s too steep to go in there – or flame length and rate of spread will keep us from going direct and go indirect,” Mack said. 

An indirect attack includes strategies that consider a fire might be fought over a longer time than what direct attack tactics can address. 

“When engaging in prolonged fire response we look at the long-term potential of a fire and determine a specific strategy for how to effectively engage that fire,” Bunch said.  

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Firefighting strategy and tactics 

Planning a prolonged wildfire response has two aspects: strategy and tactics. 

“A strategy is an overarching plan that helps us prioritize engagement on a wildfire,” Bunch said. “When executing a strategy, on-the-ground tactics determine how we accomplish that strategy. Strategies and tactics need to be well-aligned to be successful.” 

Developing a strategy entails comparing the risk a wildfire poses to things that are collectively valued – homes, businesses and critical infrastructure, as well as cultural, recreational and aesthetic resources – that are threatened by wildfire. 

Risk is elevated in certain situations due to a variety of factors that can make fire more aggressive, such as steep canyons, strong winds, dry vegetation and other environmental conditions. 

When thinking about value, incident managers consider what they want to protect and then establish priorities. Those priorities help define where firefighting is focused when resources are scarce. 

Establishing a strategy is an ongoing process. As a fire gets established, the strategy becomes dynamic and reliant on evolving tactics to be successful. 

On a tactical level, fighting fire involves depriving a blaze of two critical elements: heat and fuel. 

Areas with active burning are cooled by using water or retardant. Firefighters can also shovel soil on a burn area to cool it down. 

In terms of reducing fuels, part of that involves cutting underbrush and trees out of areas in a containment line, but also in places that fires are burning toward. 

Establishing containment lines happens when firefighters hem in a fire by removing vegetation to bare earth in strips that separate a burn area from unburned land. If fire were to spread to these lines, it would run out of fuel and likely stop there. Containment lines are created, either by hand crews or with bulldozers, to first create a safe area by the back end of the fire, then up its flanks going to the fire’s leading edge. 

Firefighters can use natural and man-made geographical features to further establish a defensive perimeter. Ridgelines or rivers can be tied into containment lines built by fire crews. So can roads or existing cleared areas called fuel breaks. Anywhere fuels are greatly diminished or absent make excellent features that can be used to halt advancing wildfire. 

Protecting homes, businesses and critical infrastructure are also part of any fire management plan. But when fire approaches the places where people live and work, extra safety measures are needed. 

Fire officials consult with local authorities about the possibility of evacuation; local law enforcement enforce evacuation orders. 

“Law enforcement has final say on evacuations,” Mack said. “That’s their role in these incidents.” 

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Firing operations 

Additionally, firefighters fight fire with fire. 

Incident commanders will create a strategic firing plan that takes terrain, weather conditions and wildfire behavior into consideration, with the idea of using low-intensity fire to create zones in front of and at the flanks of a fire that will slow or stop advancing wildfire. 

Tactical firing operations are individual actions using fire in specific areas supporting the overall firefighting strategy. Firefighters can start low-intensity fires in strategic areas, such as ridgetops, to let fire slowly advance downslope toward the flanks of a fire, preventing wildfire spread and corralling the blaze into a more confined area. 

In addition to longstanding tactical firing techniques, drone technology has become increasingly important. Drones can be used to drop devices the size of ping-pong balls to create low-intensity fire in critical areas that are difficult to reach, and do it any time of day. 

“The drones are game changers for us because we’re able to control fire at night in places where we can’t put humans and haven’t been able to for 90% of my career,” said Mack, whose firefighting days span 28 years. “So having those tools is really helping us with success in putting those fires out.” 

During these operations, firefighters look for spot fires – small fires outside containment lines that can be started by embers carried by the wind, or burning material that rolls downhill into unburned areas. When a spot fire is found, crews are sent to extinguish it. 

Adding complexity to fighting wildfire are all the variables related to weather. 

During the day, warm air rises and winds tend to blow uphill. At night, cooler air sinks causing those winds to blow downhill. Rising or falling humidity can either slow or accelerate fire spread. Changing weather systems can bring higher wind speeds – making a fire more likely to intensify – or precipitation. Rain or snow can significantly reduce fire intensity, but storms can also bring lightning – one of the major sources of fire ignition. 

Wildfires are dynamic. Firefighting conditions can change daily, or even hourly. As conditions change, so do tactics and strategies. For that reason, new fire plans are developed daily to account for those changes, Mack said. 

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Finishing the fight 

Containment of a fire is a gradual process, and fire crews declare containment conservatively. When the fire’s spread is halted, authorities will announce that forward progress has been stopped.  

As a fire gets closer to containment, fire crews engage in mop-up duties and resources will gradually demobilize. When the fire is out, rehabilitation work begins. 

Mop-up happens during and after the fire. Crews look for hot spots in a burn area, dousing them with water or soil. 

“Mop-up is arguably the most critical part of fighting a fire,” Bunch said. “It is where we actually put the fire out and ensure it cannot come back to life and spread again.” 

Rehabilitation involves repairing damage created by hand-cut and dozer-cut containment lines. Water bars are built to temper the effects of post-fire erosion. Temporary access roads are closed, often by installing large rocks or logs to prevent the public from traveling in areas where bulldozer paths were cut. 

In the days and weeks after a wildfire, the burn area will be monitored to make sure no new fires emerge. 

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Protect yourself 

For the public, it’s important to know how to find reliable information about wildfires. 

Look for information on local alert systems; the Office of Emergency Services; social media channels for the Forest Service, Cal Fire and local law enforcement; and sandwich boards that are installed in fire-affected communities. Daily briefings are streamed and recorded online, and in-person community meetings are routinely held by incident management teams.  

“It’s better to know where to get that information before a disaster happens,” Mack advised. 

His caution to people who are in an area threatened by wildfire is simple: Don’t hesitate to leave when told to evacuate. 

“If there’s an evacuation order, leave. Do not stay. Don’t think that you know better.” 

“The worst time to start planning for an evacuation is during an active wildfire,” added Bunch. “Plan early and know the evacuation protocol and alert system for your area.” 

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KNOW YOUR TERMS: FIGHTING WILDFIRES 

• Aircraft: Helicopters and fixed-wing aircraft. They can be used for dropping water or retardant or for in-air observation of a fire.
• Complex: Two or more individual fire incidents located in the same general area which are assigned to a single incident commander or unified command.
• Containment: The status of a wildfire suppression action signifying that a control line has been completed around the fire, and any associated spot fires, which can reasonably be expected to stop the fire’s spread.
• Control line: Constructed or natural barriers and treated fire edges used to control a fire.
• Direct attack: Any treatment applied directly to burning fuel such as wetting, smothering or chemically quenching the fire or by physically separating burning and unburned fuel.
• Engines: Wheeled firefighting vehicles; fire trucks.
• Extreme fire behavior: A level of fire behavior characteristics that ordinarily precludes methods of direct action. One or more of the following is usually involved: high rate of spread, prolific crowning and/or spotting, presence of fire whirls, or a strong convection column. Predictability is difficult because such fires often exercise some degree of influence on their environment and behave erratically, sometimes dangerously.
• Fire line: Strip of ground which is scraped or dug to mineral soil.
• Hotshots: Fire crews used primarily in hand-line construction. Hotshots are used to establish fire lines where hose lines cannot reach, whether that is too far from a tanker truck/water source, or too far uphill for pumped water to reach. Used mostly in extended attack situations and on large fires.
• Indirect attack: When a direct attack isn’t feasible, firefighters will use the closest geographically defensible locations to contain a fire. Firefighting strategy that includes long-term actions which take into consideration that the fire might be fought over a longer time than what direct attack tactics can address.
• Overhead support: Management support beyond an engine captain or other on-scene supervisors. The larger or more complex a fire is, the larger and more experienced the overhead support team assigned to a fire will be.
• PODS: Potential Operational Delineations are units that are bounded on all sides by usable fire control features such as roads, ridgetops, fuel transitions, bodies of water, etc.
• Slop over: A fire edge that crosses a control line or natural barrier intended to confine the fire. Also called breakover.
• Suppression: All the work of extinguishing or confining a fire beginning with its discovery. Full suppression implies an overall strategy to “put the fire out” as efficiently and effectively as possible while providing for firefighter and public safety.
• Smoke jumper: A specifically trained and certified firefighter who travels to wildland fires by aircraft and parachutes to the fire. Smoke jumpers are called up when a fire is burning at distances prohibitively far to hike into.
• Strategic firing plan: A plan using tactical firing operations to contain and extinguish a wildfire. Low intensity fire used along the inner edge of a fire line to consume the fuel in the path of a wildfire that makes it possible to fight the fire on firefighters’ terms. Sometimes known as backfiring.
• Tactical firing: Low-intensity firing operations where a specific area in the projected path of a fire is burned to starve the main fire of fuel, stopping its advance. Sometimes known as burnout.