Forest health project begins at Butano State Park

The process of mowing and mulching is called “mechanical mastication” and is a more careful, site-specific process than clear-cutting, said Kellyx Nelson, the executive director of the San Mateo RCD. Both mechanical mastication and prescribed burns are examples of “low-level disturbance,” which is crucial to forest health. 

“These ecosystems evolved with disturbance, including fire,” Nelson said.

When disturbances like fire are suppressed, she said, overgrown forests are more vulnerable to extreme wildfires and store less carbon. The Forest Health Project is like a “reboot” that mimics natural disturbances to improve the biodiversity and resilience of the park. 

Though the project is imitating natural disturbances, human-caused disturbance has long been part of local ecosystems. Cultural burning practices used to be part of indigenous land management in the region, said David Cowman, a forest ecologist at the San Mateo RCD. According to California State Parks, Butano State Park lies on land once managed by the Quiroste tribe.

For around the past 14,000 years, fire has been the most prevalent form of disturbance in California, said Tim Hyland, the natural resource manager for the Santa Cruz district of California State Parks.

“Fire is the most powerful land management tool that humans have ever used,” he said.

However, when local lands started to be protected from mining, logging and grazing, they were also protected from natural “disturbance regimes” like fires, landslides and floods. 

The loss of these disturbance regimes can cause biodiversity loss, but also has dire implications for wildfires. If fire policy is “put out every fire you can put out,” as Hyland described it, the only fires become the uncontrollable, destructive ones that have become the norm during fire season. 

After years of fire suppression, prescribed burns will have to wait until heavy machinery has cleared out dense vegetation. 

“The fuels are too dense, the road infrastructure isn’t, kind of, beefy enough to do prescribed fire currently,” Cowman said. “It would burn too hot, it wouldn’t be at the settings that we would want to burn the park at.”

The Forest Health Project was still in its planning stage when the CZU Complex fire burned through the park in 2020. The fire damaged the park and caused closures, but it also gave the project leaders a chance to reevaluate their strategy and add more acres to the project. 

“The fire kind of provided us with an unprecedented opportunity to reintroduce this disturbance,” Cowman said. “It kind of wiped the slate clean.” 

Now that work on the project has started, Cowman’s focus is on developing “treatment prescriptions” for the mechanical mastication stage. This process involves sending biologists, foresters and archaeologists through a section of forest to decide how to tackle it. They mark important plants, such as trees with nesting birds, and develop a site-specific plan for mowing and mulching. 

The project is expected to cost $1.8 million, said Cowman, and is funded by California Climate Investments and California State Parks. It will cause short-term closures of specific roads and trails, and is estimated to be completed by late 2024. 

The Forest Health Project is intended to make the park less susceptible to wildfires like the CZU Complex fire, but there’s more to it than just mowing overgrown fuels. 

“Yes, we’re reducing fuels, but our goal in [State] Parks is to preserve that biological diversity,” Hyland said. “That is done by allowing these natural processes to happen, or assisting them to happen.”