It took 37 days to contain the CZU Lightning Complex fires that covered over 86,500 acres in San Mateo and Santa Cruz counties, but the recovery process for charred campgrounds and forests in the Santa Cruz Mountains is only beginning.

Significant portions of San Mateo County's Butano State Park, including its secluded, redwood-filled canyon, and some of the Girl Scout camp had burned, according to staff of Peninsula Open Space Trust (POST), a land conservation nonprofit headquartered in Palo Alto. Along the coast, the historic farmhouse at Pie Ranch in Pescadero also fell victim to the fires. Its crops, covered in ash, had to be abandoned.

Nearly 2,700 acres also burned in Pescadero Creek Park in Loma Mar, according to the National Interagency Fire Center.

The devastation spanned beyond homes and businesses in communities such as Boulder Creek and Bonny Doon in Santa Cruz County. As much as 40% of redwoods in the Santa Cruz Mountains may have burned, along with historic buildings, campgrounds and visitor centers, according to estimates based on comparisons between maps of the redwood locations and the burned area, POST Chief Marketing Officer Marti Tedesco said. She noted that research has not yet been conducted in the area to see how many trees were directly affected.

The fires burned through all of Big Basin State Park and POST-protected Little Basin campground in Santa Cruz County. It impacted educational structures at Swanton Pacific Ranch, which is owned by California Polytechnic State University, POST staff said.

The most heartbreaking loss was the San Vicente Redwoods, a nearly 9,000-acre preserve co-owned by POST and the Sempervirens Fund. It could be months or years before the land recovers, POST President Walter T. Moore said in a Sept. 14 blog post.

"For me, these were more than just 'structures,'" he said of the visitor centers, campgrounds, bridges and cabins that the fire destroyed in the redwood groves such as Big Basin and Little Basin. "They were places where we gathered for generations with our friends and families, places where we made memories and found ourselves surrounded by the splendor of the redwood forest.

"As for the forest itself, it will be months, if not years, before we can fully assess the impact. That said … fire in this landscape can be healthy and beneficial for the redwood forest as it is very well adapted to survive fire. In fact, fire is an integral part of this environment and helps to maintain the health of the ecosystem. Redwood trees, especially old growth, can withstand fire — and early indications are that many have survived.

The CZU fires burned at different intensities across the landscape, however. "In some places it may have positive impacts on the ecosystem, in others it may have burned hotter leaving the soils especially vulnerable and causing it to take longer for plants to grow back," he said.

The area is still largely too dangerous to enter for a full assessment, Tedesco said during a recent phone call with this news organization.

"It's a tragedy we're all reeling from. Where do we start?" Tedesco said.

San Vicente, a celebrated acquisition made in 2011 by POST, the Sempervirens Fund, Save the Redwoods League, The Land Trust of Santa Cruz County and The Nature Conservancy, is a second-growth redwood forest, meaning it was previously logged for timber and sprouted or had new trees planted. Yet, the property has some of the last remaining original, ancient old-growth redwood and Douglas fir trees in the Santa Cruz Mountains. It is a prime nesting habitat for marbled murrelets, an endangered bird species.

Second-growth trees grow more densely, can be more susceptible to disease and are less resilient than old-growth forests. Combined with unusual climate conditions and drought-induced stress, they were the perfect hosts for a fast-moving, intensely burning wildfire driven by winds, Noelle Chambers Thurlow, vice president of conservation for POST, said by phone. Most of the 8,532-acre property was scorched by the fires.

"The property burned from top to bottom. All of us are devastated that this property would've burned," Tedesco said, adding they previously put in fire breaks and conducted prescribed burns to help protect the forest.

The redwood forest is getting drier, however, and the summers are longer with shorter rainy periods. Combined with a large amount of vegetation and nonnative, invasive species, the CZU fires burned very hot in some areas and moderately hot in others. It's not known how the redwoods, which evolved with fires, were able to survive after the intense heat nor whether seeds in the soils survived, Thurlow said.

But there are some signs the forest and grassland are already starting to resprout. Thurlow said she has seen a few photographs taken by ecologists showing green shoots emerging.

"It's hard to answer when (the forest) will come back. We can only speculate. One year from now we'll have a much better idea," she said.

Land managers, with limited staffing, have a huge job ahead of them, she said. Before the rains, they'll need to assess areas that could erode and the impact of the fires on water quality, for example. Tedesco noted there hasn't been a significant wildfire in the whole Santa Cruz Mountains range for more than 100 years, and there's not much information to rely on locally about how major fires will impact the forest, how it will come back and how the fires might affect wildlife.

The CZU Complex fires and the adjacent SCU Lightning Complex fires in the Diablo Range could have significant implications to regional wildlife corridors, since animals move between the two ranges for survival, Moore noted.

"It will take us a long time to understand the effects of fire on this habitat already strained by urban encroachment," Moore said.

Thurlow said biologists are currently using wildfire cameras to study the San Vicente forest.

Moore said the fires affected not only the forests but also a whole way of life.

"The fire was also a huge threat to farms in and around the town of Pescadero and more broadly along the San Mateo County coast. Many of these farms operate on POST-protected land and were evacuated with little warning. Forced from their operations for several weeks, their businesses suffered as they lost their ability to harvest and distribute their products," he said.

As they assess the fire damage and study how the forest regenerates, Tedesco said researchers and land managers will also take a close look at how they can avoid past land-management practices that have contributed to the devastating fires.

"Society hasn't necessarily served the open spaces as well as it could and created a vulnerable forest 100 years on," she said.

Donations toward the redwood forest restoration can be made to POST at openspacetrust.org or to the Sempervirens Fund at sempervirens.org.

Editor's note: This story clarifies that the 40% figure is an estimate of redwoods burned and a scientific study of the damage is pending.