21 September 2020

3 minute read

North America

A case in point: Chileno Creek, a waterway that winds through Chileno Valley Ranch outside of Petaluma, California. The 100-foot-wide restoration area is home to steelhead trout, coho salmon, egrets, deer, badgers, insects and other creatures that flourish in riparian zones like these. Willows, oaks and native shrubs multiply along the banks, reducing erosion, nourishing the soil and capturing carbon to help reduce climate change worldwide.

Twenty years ago, Chileno Creek was a wasteland.

“It looked like a moonscape,” says Sally Gales, who owns and operates Chileno Valley Ranch with her husband, Mike. “The slopes were denuded and there were cows hanging out in the creek. We called UC researchers and the Marin Resource Conservation District, and their science and support helped us turn it around.”

On a recent spring day, the Gales welcome us to see Chileno Creek, the first of many waterways they revegetated over the last few decades. CA&ES researchers have collaborated with thousands of ranchers and fellow scientists on rangeland restoration projects like these. Sally leads the way through a lush meadow. The Gales’ springer spaniels, Pup and Pip, romp ahead and the scent of fresh grass rises like mist.

Common ground

More than one-third of California, 38 million acres, is rangeland. Most of the land is privately owned and managed for livestock. Grazing offers many environmental benefits like keeping weeds and other invasive species in check, providing water storage and carbon sequestration, and supporting habitat for plants and animals found nowhere else in the world.

But problems arise, like erosion and downstream water-quality issues, if rangeland is overgrazed or cattle congregate in creeks and trample delicate riparian zones. Conditions vary in terms of soil, slope, climate and vegetation, so researchers offer a suite of ideas for how to protect riparian areas and keep erosion in check. Examples include building strategic fencing, spreading gravel on creek crossings to help absorb hoof impact, rotating herds among pastures and maintaining a diversity of native grasses.

“We don’t tell ranchers and regulators which tools to use,” says CA&ES Professor and Cooperative Extension Specialist Ken Tate, who joins us on the day’s tour. “We identify what works and what doesn’t work so they can design a rangeland management plan that is feasible and sustainable.”

Watching the water flow

To reclaim Chileno Creek, Sally and Mike first fenced off all the creeks and provided spring-fed water troughs so their herd of 100 cattle had what they needed away from running water.

Then Sally “planted” the creek.

“You start by poking a willow sprig in the creek bed, along with a lot of other native plants and shrubs,” Sally says, her smile broad beneath her Chileno Valley Ranch cap. “You nurse it a little and then watch it grow.”

As the creek grew, David Lewis, director of Cooperative Extension in Marin County, helped measure whether restoration projects like these could capture carbon as well as control erosion. It could.

“Revegetating riparian zones to control erosion provides a carbon sequestration service that is valuable and substantial,” says Lewis, hiking alongside Tate to Chileno Creek. “Revegetation of streambanks helps ranchers control erosion and mitigates climate change, which benefits us all.”

We arrive at the banks of Chileno Creek, which rolls in folds like the back of a dog’s neck. Dragonflies dart across the surface and birds call from distant trees. The morning sun shines so gently on the water that the creek looks lit from within.

“It’s amazing what you can build with teamwork and a little care,” Sally says. “Chileno Creek supports people, animals, insects, birds, fish and plants that all deserve a place in this world. There’s no telling what tomorrow will bring, but restoration gives us hope.” •