Grazing in the Sonoma County Regional Parks for Vegetation Management

By Carol Benfell

There may be drought and wildfires and political despair, but decades after people thought they were gone forever, wildflowers are blossoming again in a corner of Petaluma’s Helen Putnam Park.

It’s been a sheep solution: Carefully controlled grazing has eliminated many of the non-native, invasive plants that were choking out flowers and native grasses.

Not only that, the sheep have created a significant fire break because the same invasive plants that choke out wildflowers are fast-burning fuel for wildfires.

“A lot of California native grasslands species are choked out by the very same European grasses that provide flash fuels for wildfires,” said Melanie Parker, deputy director and natural resources manager for Sonoma County Regional Parks.

“Restoring grazing controls these invasive grasses, allowing the native plants to express themselves again. Grazing also rebuilds the soil, so it holds moisture and recharges the aquifer,” Parker said. “We are restoring a whole ecological system, and that’s what’s exciting about this project.”

The park system oversees more than 11,000 acres, 56 parks and open spaces, and 150 miles of trails. Sheep grazing has been so successful at Helen Putnam Regional Park that officials want to extend it to other parks as well.

“You can go to Helen Putnam and see native grasses and wildflowers we haven’t seen in decades,” Parker said. “We would definitely like to expand the program, and we would add goats to the mix.”

Other parks have had equally good results: The National Park Service used goats to chomp down overgrown ivy and blackberry at Fort Mason in San Francisco. The U.S. Fish and Wildlife Service is permitting grazing on the Santa Rosa plains to protect endangered plant and animal species. The East Bay Regional Park District in Oakland grazes cattle, sheep and goats on about 80,000 of its 120,000 acres to reduce fire risk and improve habitat for native plants and wildlife.

“Grazing is our primary tool for management of vegetation,” said Denise Defreese, wildland vegetation program manager for the East Bay Regional Park District. “It’s the most economical way to manage vegetation for fuel reduction and maintain habitat for federally and state listed (endangered) species.”

Grazing works well because it mimics the ancient landscape in which native plants evolved, a time when prehistoric grass grazers—mammoths, camels, antelopes and elk—nibbled down grasses and broke up the soil with their hooves as they moved.

So Regional Parks is reintroducing grazing—highly controlled and tightly managed. Animals graze for a short time, then are moved away, giving the land time to recover. During times of rest, new plants take root, perennial plants sprout, nutrients are absorbed, and roots loosen compacted soils. Grazing is cost-effective because it reduces the need for both herbicides and mowing.

“It costs too much to do the mowing that’s needed, and equipment itself can cause sparks and is a potential ignition source for a fire. We’d like to replace the mowing equipment and expand the number of acres we graze,” Parker said.

Sonoma County Regional Parks already allows cattle grazing by private ranchers at Tolay Lake, Taylor Mountain, Crane Creek and North Sonoma Mountain regional parks.

Three years ago, parks officials introduced sheep at Helen Putnam Park, a 216-acre wilderness park southwest of Petaluma. This year, grazing was added on 34 acres along the Laguna de Santa Rosa Trail.

“The project has to balance the need to reduce fuels and fires with managing to increase biological diversity,” Parker said. “We’re monitoring closely to make sure we’re achieving both those ends.”

At Putnam park, the results of careful grazing are becoming clear, and officials have high hopes for the Laguna trail as well.

“We’re seeing some really lovely Lupinei n the firebreaks we’ve grazed at Putnam and lots of tall perennial grasses,” Parker said. “We are planning annual monitoring of endangered Sebastopol Meadowfoam and hope to see more plants in the spring.”

Regional Parks contracts with Sweetgrass Grazing in Petaluma for the work. Aaron Gilliam, who has a degree in Environmental Studies from UC Santa Barbara, is the company owner – and its entire staff.

Gilliam rents the sheep from nearby ranchers and keeps them in an electric netting paddock while they graze. He and his two herding dogs, Isha and Ulli, stay with the sheep as much as 24 hours a day, and move the flock from place to place almost daily. Each of Gilliam’s 280 sheep will eat five to seven pounds of grass a day, as well as weeds and other broad-leaf plants.

He usually works 12 hours a day, 10 days at a stretch, making sure the sheep are safe and have plenty of water. He also monitors what they eat: If the grass is too dry and lacks nutrition, he must supplement their diet.

It’s not a job for the faint of heart. Gilliam gets poison oak regularly, and battles ticks, wasps and spiders while watching out for rattlesnakes and gopher holes.

“What makes it worthwhile to me is that I can go to bed at night believing that my niece and nephew will inherit a slightly better world than the one I inherited. At least that’s the hope,” Gilliam said.

A measure on the November ballot, if approved by voters, would allow Regional Parks to more quickly expand sheep grazing to other parks, including Gualala Point, Carrington Ranch, Foothill, Shiloh Ranch, Sonoma Valley and Cloverdale River regional parks.

The Sonoma County Parks Improvement, Water Quality, and Fire Safety Measure would impose a one-eighth-cent tax on sales countywide for a 10-year period, the equivalent of 12 cents on $100. The measure is expected to generate $11.5 million annually, $7.6 million a year going to Regional Parks and $3.8 million a year going to the county’s nine cities.