How Prescribed Burns Build Forest Resilience

Last Friday, CAL FIRE made history in Soquel Demonstration State Forest. In an attempt to “fight fire with fire”, the suppression and forestry teams came together to execute the first-ever prescribed burn in the 2,600-acre property.

We were fortunate enough to receive an invitation to observe the prescribed burn alongside other forest partners. Read on for all that we learned.

We gathered in the Highland Way parking lot at 10 a.m. for a briefing on the day and a welcome circle. It was strikingly similar to the beginning of a Dig Day–everyone stood around and got to know one another in the cold morning air.

Once we carpooled to the burn site, we got all dolled up in Nomex fire-resistant outfits and hard hats to protect ourselves from any rogue embers.

Prescribed burns are an important fuel management tool, and essential to maintaining a healthy forest. When done properly, they get rid of dead trees and vegetation, reduce the risk of catastrophic wildfire, and rejuvenate the forest by supporting species that need fire to reproduce and thrive.

Native communities have generations of experience in managing California’s landscape with controlled burn techniques. Despite their success, prescribed burns were not readily practiced post-colonization due to a lack of knowledge of the landscape and inflated weariness about potential wildfire risk.

Prescribed burns treat an area evenly, and effectively remove all the ladder fuels across a plot of land. If a plot of land has a higher wildfire risk or only requires treatment in small areas, land managers may use a “burn pile” technique to reduce fuels instead. The type of burn chosen depends on the landscape, weather conditions, and overall goals for the fuel management.

A lot goes into planning a prescribed burn, and things have to be just right for a burn to take place. On Friday, we learned that CAL FIRE staff started planning for this burn over a decade ago! Getting through the approval process takes time, and both the forest and fire protection teams must collaborate on burn plot locations, duration, and necessary weather conditions, just to name a few.

The CAL FIRE team had an army of staff on site for safety and monitoring. Our Trail Crew’s jealous of their gorgeous custom fire truck and dozer…

1. Choose a site. This 4-acre burn took place on the lower helipad in SDSF. The helipad was an ideal location due its popularity for emergency support, the dead tanoak and madrones present throughout the site (fuel for a wildfire), and the mixture of vegetation types in the area.
   
   When choosing a burn site, sometimes planners will review existing burn scars in an area and try to use them to create a natural boundary for prescribed burns. Since a burn scar has already undergone fire, planners can be more certain that a prescribed burn is unlikely to spread in that area.
   
   

2. Create a fire line. The CAL FIRE team will cut a thick circumference around the selected burn plot, either by hand or with a dozer if the geography allows. This removes fuels from a large boundary of the plot, and reduces risk of the fire spreading outside of the selected area.
   
   

3. Remove fuels by hand. Using chainsaws and hand tools, the team will remove any small trees, rogue branches, and overgrown brush. By taking the time to remove these fuels by hand before a burn, the fire becomes much more predictable and manageable.
   
   

4. Run hoses. Large hoses hooked up to water tanks are then laid along the outer boundary of the selected burn site. This is just another precaution taken to prevent wildfire risk.
   
   

5. Burn!
   
   

6. Assess for danger. After the burn goes out and the area cools, CAL FIRE teams will scout the burn plot for potential danger, and remove hazards like dead trees and unsafe branches.
   
   

7. Treat the area. Following hazard removal, CAL FIRE’s forestry team will monitor the landscape and provide any treatments necessary to keep the vegetation in great shape. At this plot, they plan to remove French Broom, which is an invasive species expected to boom post-burn.

CAL FIRE suppression team members drip a diesel/gas mixture on the brush they want to burn.

The success of this first prescribed burn encourages future burn activities, and creates an important anchor plot for the forest. CAL FIRE officials can burn neighboring plots of land, because the burn scar from Friday’s activities creates a natural boundary and cutoff for future flames.

CAL FIRE is also evaluating ways to incorporate burning and fuels management into SDSF’s timber harvest activities. Sometimes there is a lot of wood left on the ground after harvesting timber from a forest… for example, there is currently leftover wood on Sawpit Trail right now.

CAL FIRE leadership is looking at what to do with that fuel, and hoping to expand this type of work to get that fuel managed properly. When asked, CAL FIRE let us know that they are considering either conducting a prescribed burn along the trail or hauling the leftover timber to a location where they can use a curtain burner (a box that produces a smokeless burn) or masticate the area. They’re working with expert forestry consultants to form the best possible management plan, and expect to start work in the months ahead.

We’re grateful that we got to go out and view Friday’s burn, and want to thank the Cal Poly Swanton Pacific Ranch team for their efforts to educate the public on the benefits of prescribed burns. We are hopeful for the future of this important recreation area. If you’d like to get involved in SDSF management, please come out to one of our upcoming volunteer events! We have a Dig Day planned for 11/19, and plenty of volunteer events out in the forest this season. Check it out via our events calendar here.