Years after Redwood National and State Parks began removing old logging roads and thinning out trees to accelerate old growth conditions on former timberland, the two agencies are partnering with Save the Redwoods League to focus restoration efforts on the Prairie Creek and Mill Creek drainages.

The 100-year-old nonprofit will provide funding as well as its expertise in science and management to help scientists with Redwood National and State Parks treat 10,000 acres of redwood forest and decommission more than 8 miles of logging roads that are no longer in use, said Sam Hodder, president and CEO of Save the Redwoods League.

The collaboration, dubbed Redwoods Rising, became official Friday with the signing of a memorandum of understanding between the National Park Service, California State Parks and Save the Redwoods League at Prairie Creek Redwoods State Park.

One area, the Mill Creek watershed, is between Del Norte Coast and Jedediah Smith Redwoods state parks, Hodder said. The other area is on national park land near Prairie Creek Redwoods State Park, he said.

“Many people think of Redwood National and State Parks and think of the extraordinary old growth of Prairie Creek and of Jed Smith and of the Redwood Creek drainage,” Hodder said. “But in reality that old growth represents only a third of the landscape of the parks. Fully 2/3rds are young recovering (forests). They’re forests that have been aerially seeded with Doug fir. In order to restore function to the ecosystem it really requires us to get in there and re-set the balance of both the species and the distribution of the trees.”

Redwood National and State Parks has been restoring former timberlands for decades, said Leonel Arguello, the parks’ joint chief of resource management and science. Restoration work began in the Mill Creek area since the mid 2000s, and the national park has been thinning out trees and decommissioning roads near the headwaters of Prairie Creek since 2000, he said.

The Redwoods Rising project will continue work in the Mill Creek area and will shift focus from the headwaters of Prairie Creek to its main stem, Arguello said. These are forests that are dominated by exotic conifers such as Douglas fir and pine, he said, and in some areas have 1,000-1,500 trees per acre.

Thinning out some of the trees would allow more sunlight to reach the forest floor and would start the development of an understory, a layer of vegetation beneath the forest canopy, Arguello said. A new cohort of seedlings would begin to grow, providing the next generation of trees that would then create a vertical structure, he said.

“If you’re standing on the ground looking up, instead of looking up at bare stem trees until you get to the canopy, you would begin, over the next several decades, of getting a vertical distribution of trees in the mid canopy and two-thirds canopy and get a shrub layer at the base,” Arguello said. “That provides maximum habitat for species. A long term benefit is by thinning we accelerate the ability for the trees we leave behind to grow a little bit faster towards old growth characteristics.”

Visitors to the parks 150-200 years from now may be able to see the beginnings of an old growth forest develop in those restored areas, Arguello said.

Another component of the Redwoods Rising collaboration is the removal and repurposing of old logging roads, Arguello said. These roads were poorly built for the area’s rainy environment and bleed sediment that finds its way into the local watershed, he said.

However removing old logging roads is costly work, Arguello said. Doing the full re-contouring and removal of road on landscape could cost $300,000 to $400,000 per mile, he said.

“If you have 10 miles of road that’s $3 million to $4 million,” he said. “It’s something that is difficult to find that level of funding and support. This partnership is intended to leverage the strengths of each of the partners — national park, state park and the league — and working together collaboratively to raise the funds that are needed to do the work.”

More than 70 miles of road have been removed in the Mill Creek area, but more than 200 miles remain, said Jay Chamberlin, California State Parks’ chief of natural resources.

“Mill Creek is an extraordinarily rich salmon habitat, coho salmon habitat,” he said. “It’s one of the most productive coho salmon streams in California and so when it is getting impacted by sediments coming off from old roads, it’s a major impact species-wide for coho, which are really endangered.”

Old growth forests also house other endangered species such as the marbled murrelet and the Humboldt martin, Chamberlin said.

The Redwoods Rising collaboration is mentioned in the Save the Redwoods League’s first “State of Redwood Conservation” report. Released this month, the report states that only 22 percent of the coast redwood forest is protected against commercial logging, subdivision and development and nearly 40 percent suffer from being next to roads, residential development and agriculture.

Emily Burns, director of science for Save the Redwoods League and a co-author of the report, said finding out that 40 percent of the entire 1.6 million acres of redwood forest is impacted by human infrastructure came as a huge surprise.

“It’s a motivating factor for why we want to continue to protect redwood forests and why we want to do restoration work,” she said, noting that old growth redwood forests store more carbon above ground than any other forest on the planet. “They really are a tremendous aid. We’re in this era of climate change and global warming, by holding so much carbon dioxide in their wood. Redwood trees are incredibly good at retaining carbon whether they’re alive or dead. They do not decompose quickly.”

Chamberlin said the restoration work supported through Redwoods Rising will benefit visitors in the near term by helping them understand that 95 percent of California’s old growth redwoods were logged. But, he noted, it’s not a “bad-news only story.”

“This is a really hopeful story that says we can take steps in our lifetime that will restore the forests for future generations,” he said. “I think that’s a really hopeful story. It’s a way to engage people. They’re going to go to old growth groves and they absolutely should, there’s nothing more inspirational that I can think of. But when they step out of those groves, they can step into a place where we’re restoring that landscape in time, over hundreds of years. It’s an important opportunity to help educate people about our past and where we’re going and the steps we’re taking.”

Of Redwood National and State Parks’ 120,000-acre footprint, only 40,000 acres is old growth forest, Arguello said. Having an intact ecosystem with redwood and Sitka spruce that future visitors enjoy was the vision when the state parks were created in the 1920s and the national park was created in 1968.

“But it does not happen overnight,” he said. “Visitors got to know that it takes time and you got to work diligently and carefully and hopefully in time, the results we see the results of our thinning already and we know that in the long term we’re going to be in better shape. The park will be in better shape.”

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