California Wildfires: Training for a Tough Season

“We did start hiring our seasonals as early as January, which is something I’ve never heard of,” Head said. “And Southern California never even saw an end to fire season.”

It was the same for the Forest Service. “We never really had an off season,” said Shawna Legarza, the regional fire and aviation director with the Forest Service in California. “Usually we get some time off during the holidays. We had fires right before Christmas. We had fires in Northern California in January. We had fires in Central and Southern California in February. We’ve been busy.”

Last year, more than 570,000 acres burned in wildfires in California. The Rim Fire, near Yosemite, was huge, but overall, total acres burned in the state was near average.

This year, CalFire is preparing for a busy season by hiring extra staff — firefighters and also inspectors to check whether homeowners have cleared vegetation to create extra space around their houses, called “defensible space.”

Pre-Fire Science

“A lot of the preparedness efforts we make cost money. We have to justify that with evidence,” said Tom Knecht, a fire captain and pre-fire engineer with CalFire. His job includes collecting some of that evidence.

Because, though it may seem like common sense that it’s dry out there, there is a science to knowing how dry, and to knowing when the threat of fire is at its worst.

Knecht took me up a trail in the Las Posadas State Forest, about 20 miles northeast of Santa Rosa. The trail was lined on either side by a plant called chemise that grew higher than our heads. “It looks a lot like rosemary,” Knecht said, as he snipped twigs off the plant with a pair of garden shears and stuffed them into a plastic container shaped like a water bottle.

He weighs the chemise he collects, then dehydrates it and weighs it again. The difference between those two numbers tells him how much water is in the plant; this is called the live fuel moisture. (As opposed to dead fuel moisture, another measurement tracking the water content in dead trees and branches.)

At this point in the year, there’s still a good amount of water.

“We’re still seeing the plants taking on water,” Knecht said. “So they’re still getting moisture out of the ground. They’re still growing. You can see the new growth, they’re getting ready to flower. That whole time the plant is full of moisture.”

Eventually, the plants will begin to go dormant. That’s the moment Knecht is on the look out for.

“We really want to know when it turns the corner, when it stops taking on water and then starts to dry out,” he said. When the chemise is growing, it could burn, but the fire would be slower and less intense. Once the plant is dormant and dried out, its presence marks the places that could burn hot and fast.

Knecht said the plants look like they’ll be turning that corner sooner this year. “The plants, although they’re taking on moisture and have new growth, they’re behind where they were last year this time,” he said. “I expect to see them dry out earlier, turn the corner earlier, be dormant earlier.”

Knecht does these studies monthly, and sometimes more often than that. Fire officials look at the live fuel moisture measured in various plant species all around the state. And they feed that into a model along with the dead fuel moisture. Then they combine that with weather conditions to figure out the energy release component. That tells them, if a fire does catch, how intense it will be.

“We look at weather every day, and the topography — we know where there’s steep ridges and hills and so forth. But the fuel moistures change, and that’s one of the things we need situational awareness of, to be able to base our actions on current and expected fire behavior,” Knecht said. “That’s why I’m out here doing this.”

Putting the Data to Use

Armed with that information, fire officials can work to ensure that firefighters and equipment like air tankers are moved to the right part of the state, and — in a year like this one — that they’re in place early as needed.

“We’re only in May and we’re seeing conditions that we would normally see in August,” said Chief Ken Pimlott, the director of CalFire. He said Governor Jerry Brown’s drought declaration in January put extra money toward firefighting. “He has made a very firm commitment that CalFire and our partners will have the resources and the funding it needs to combat this risk.”

CalFire has the budget for an extra 300 firefighters this season. Like CalFire, the U.S. Forest Service brought staff on earlier, too, and is prepared to bring firefighters in from other parts of the country.

So the firefighting agencies say they’re ready. What they can’t predict is when or how a fire will start.

“We can’t control the lightning, that’s out of control,” said Legarza. But the majority of wildfires, she points out, are human-caused. “So we can help give information to the public to help us prevent wildland fires.”

Like making sure brush and branches are cut back around your property, following rules about campfires and being careful with tools that might spark a flame. And as Smokey Bear’s been reminding us for decades, whatever you do, don’t throw that cigarette butt out the window.