Cows. Good for climate change?

By Gabriel Zucker

The Willits bypass is a stretch of the U.S. Highway 101. After being proposed 60 years ago, it was finally finished less than a decade ago. It serves an important role in decongesting Willits, diverting drivers around the small town. The bypass is also home to the largest public wetlands mitigation project in the state of California, the Willits Bypass Offsite Mitigation Project.

This mitigation project has been joined by Justin C. Luong, a rangeland resource science professor at Cal Poly Humboldt. Recently he was awarded a $520,000 grant from the California Bountiful Foundation. He is conducting a case study on the impact of cattle grazing on grasslands. This research is important because wetlands help with carbon cycling, host thousands of endemic species, and play a key role in cattle production.

“Federal government policies don’t allow for any grazing on any top of habitat classified as any kind of wetland at all,” Luong said. “Even though California state laws and science show sometimes grazing can be beneficial for managing natural systems if utilized properly.”

Luong is doing this study to better understand if cows actually play a vital role in grassland ecosystems. He is using historical data from the Mendocino County Resource Conservation District to look at the impact of removing grazing in the grasslands. Luong is also using aerial images from Google and drone images to better understand the environmental differences between grazed and ungrazed grasslands. While looking at all of these images, Luong is also taking samples at the site, inspecting the biology of the plants, trying to better understand the best traits needed for a changing environment. 

“My job is to essentially go in and evaluate how the removal of cattle grazing from these areas affected these habitats and their ecosystem properties and services, especially thinking about some of the threatened species we have out there,” Luong said. “The North Coast semaphore grass, the baker’s meadow phone. Both of these species typically require more open habitat and bare ground in order to establish well.”

Luong is trying to find the perfect combination of native plant species for grasslands to thrive. Plants like Reed Canary grass are taking over most of the space in the habitat, leaving little room for the important species mentioned above. 

“The managers on the ground have noted that oftentimes, cattle grazing is really important to remove some of that cover, open up some of that space to facilitate some of the recovery or establishment of those kinds of threatened plant species, while still supporting cattle production,” Luong said.

The reason Luong is focusing on grasslands is to highlight the importance they have. They not only support the entire cattle economy, but they hold a key role in controlling carbon emissions. In a process called carbon sequestration. They hold pockets of carbon in their roots, reducing global carbon emissions. In a study by The Conservation Fund, they discovered that wetlands store 18 to 216 metric tons of carbon per acre. Making grassland restoration an important fixture in climate conservation.

“Grasslands are really important for carbon storage and sequestration, especially with future climate risks. Because oftentimes when you have mass plant mortality, which happens in grasslands or forests you lose that carbon back to the atmosphere.” Luong said. “In grasslands, a lot of that is fibrous roots underground. We know that some native grasses that we have dug up can go up to 18 feet deep, so that carbon stays stable in the ground and helps with more stable carbon sequestration with climate change.”

Luong is going to work on this project for the next five years with Mendocino Resource Conservation District. He is hoping to reinvigorate grassland restoration by updating the data and information people have for grassland restoration. He believes that once people have the right tools, grassland restoration will be more informed and focused.

“My work often is really geared at being applied, and so I’m always trying to find real world issues that need solving now and try to work towards those solutions, those applied solutions,” Luong said.