Go to WSRB
Go to BuildingMetrix
CREATE AN ACCOUNT
LOG IN

About the Company

Who we are and how we serve insurers, agents, and Washington state residents.  

CEO Perspective

Engaging thought leadership on key insurance industry issues from our CEO. 

Meet the Team

Get to know the team behind WSRB’s trusted data and excellent customer service. 

Careers

Learn about the benefits of working at WSRB and apply for open positions.  

Underwriting Property

A guide to key risks in Washington state: fire, wildfire, and earthquakes.


Video Hub

Expert webinars, timely discussions, and in-depth conversations with industry leaders.. 

Commercial Property

Information on loss costs, policy rating, and assessment tools 


Industry Toolkit

Links to help you work smarter and serve your customers.  

Protection Classes

The evaluation process explained from start to finish.


WSRB Blog

News on emerging risks as well as our latest products. 

Library

In-depth content on essential insurance topics.


InsuranceEDGE

Weekly newsletter covering the P/C industry, curated by our experts. 

 

Preventing Fire With Fire

Robert Ferrell
May 21, 2019

For decades, we’ve learned how important it is to do everything possible to prevent forest fires. So, the idea that some fires help control forest fires might seem puzzling. But it’s true. Prescribed burns, also called prescribed fires and controlled burns, help improve forest health and reduce the risk of large, catastrophic wildfires.  

To understand the value of prescribed burns, let’s go back in time.   

More than a century ago, a series of huge forest fires along with the desire to protect commercial timber supplies led to the goal of total fire suppression — that is, to prevent forest fires from starting and to put out any fire that did start as quickly as possible.1 Over time, new firefighting methods emerged to support the goal, including airplanes and fire suppression chemicals.2   

Total fire suppression remained the U.S. Forest Service’s goal until the early 1970s, by which time scientific research had shown fires were an important part of forest ecosystems. The service began letting naturally occurring fires burn when and where appropriate.3

A firefighter monitors a controlled burnA firefighter working with the Washington DNR monitors a controlled burn.

 

Related:
Underwriting Property: A Guide to Fire, Wildfire and Earthquake Risk

 

The unintended consequence of total fire suppression 

Even with the policy change, most fires were suppressed over the last hundred years, leading to a counterintuitive result: a higher risk of intense wildfire. How’s that possible?  

Fire is a natural, regenerative part of a forest ecosystem. It kills insects that prey on trees and clears out underbrush, such as grass and fallen leaves, needles and cones.4 Underbrush is a major fuel source for fires, and when it isn’t cleared by fire or another mechanism, it accumulates.   

Fire also thins the forest. Trees need moisture and nutrients from the soil. When forests grow too dense and there are too many trees too close together, some trees won’t get enough. The undernourished trees are smaller, weaker and drier than larger, more mature trees. They become fuel similar to underbrush.     

If a fire starts in a dense forest with decades of underbrush accumulation, the fire is more likely to ignite large, mature trees, especially when those trees are dry due to drought. Fire climbing tall trees can “crown” or move from the top of one tree to another,5 meaning the fire is spreading not just on the forest floor but also above it. Soon, the fire is burning so intensely that it becomes difficult to control.    

Firefighters plan a prescribed fireFirefighters plan a prescribed fire.

 

Related:
Busting Myths about Wildfire Risk in Western Washington

 

What prescribed burns do — and don't do

Prescribed burns are not the same as wildfires, and the point of a prescribed fire is not to burn down all the trees in a forest. Instead, the fire burns the underbrush and small trees, reducing fuel accumulation.    

Prescribed burns only happen after extensive planning. Strict borders are set up surrounding the area to be burned. Firefighters monitor the borders and put out any fire that breaks through. Prescribed fires are only set under specific conditions that make controlling the fire possible, such as when winds are calm, temperatures are cool and humidity levels are moderate or high. Under these conditions, large trees contain enough moisture to resist fire. Here in Washington state, most prescribed burns take place in the fall, before forests become too wet, and in the spring, before they become too dry.      

After a controlled burn, the risk of intense wildfire in the treated area falls, especially for the following fire season. If a fire does start in a treated area, large trees are less likely to ignite, making the fire easier to fight; in some cases, the fire may go out naturally.6  

But prescribed fire is not a once-and-done project. Over time, underbrush grows back, needles and leaves accumulate, and the risk of intense fire rises.   

In fact, you may see more prescribed burns in Washington state, especially in the central and eastern regions, as part of Department of Natural Resources (DNR) programs to improve forest health. Last month, the DNR co-sponsored a training on prescribed burns for fire professionals. The photos in this post come from previous similar events. For a look at where some prescribed fires have burned, visit this link. 

Prevention is still paramount 

Prescribed burns can reduce the occurrence of intense wildfires, but we all still need to do what we can to prevent wildfires. The vast majority of wildfires — 85% in Washington state — are caused by people.7 So, everything you learned about preventing forest fires still applies today.   

For a refresher on what you can do, the DNR publishes prevention tips. 

More wildfire content


[1] Forest History Society, https://foresthistory.org/research-explore/us-forest-service-history/policy-and-law/fire-u-s-forest-service/u-s-forest-service-fire-suppression/

[2] Forest History Society, https://foresthistory.org/research-explore/us-forest-service-history/u-s-forest-service-publications/general-publications/highlights-in-the-history-of-forest-conservation/table-of-contents/after-world-war-ii-1945-1967/

[3] Forest History Society, https://foresthistory.org/research-explore/us-forest-service-history/policy-and-law/fire-u-s-forest-service/u-s-forest-service-fire-suppression/

[4] CAL FIRE, https://www.fire.ca.gov/media/5425/benifitsoffire.pdf

[5] National Park Service, https://www.fs.fed.us/nwacfire/home/terminology.html#C

[6] Washington Prescribed Fire Council, http://waprescribedfire.org/

[7] Washington State Department of Natural Resources, https://www.dnr.wa.gov/programs-and-services/wildfire-resources

Robert Ferrell, P.E. is WSRB’s Vice President of Public Protection. He leads the team that manages the insurance rating of cities, fire districts and building departments throughout Washington state. He has more than 25 years of experience in fire insurance rating.

Guy-reading-insuranceEDGE

InsuranceEDGE


Like our blog? Check out InsuranceEDGE. We curate the week’s must-read stories from top industry sources. You stay informed and save time.

SIGN UP TODAY!

You May Also Like

These stories on underwriting property

blog listing blog sign up

Sign up for our blog