Increasing amounts of carbon are being emitted into the atmosphere, playing a role in our changing climate patterns. Reducing these emissions requires policy, behavior change, and access to new technologies (among other things). While we may struggle to influence emission decisions, we may be able to help offset some. I often find myself thinking of Max Lucado’s quote “no one can do everything, but everyone can do something”—that includes cows and ranchers, too.

We typically think of grasses as the green blades we see above the ground, but their complex network of roots deserves equal—if not more—attention. Roots allow grasses to convert nutrients to forage for livestock, prevent the erosion of topsoil and store carbon in the ground through a process called carbon sequestration.

Carbon sequestration is a vital process involving the transfer of carbon from the atmosphere into the soil. This occurs primarily through plants, which absorb carbon dioxide during photosynthesis. Some of this carbon is stored in the parts of the plants that grow above-ground, while the rest of the carbon travels down to the roots, where it promotes further growth and nourishes soil microbes. As plants and microbes die, some of the carbon they stored become part of the soil.

A new research study published by a team of scientists, including Maria Silveira of UF/IFAS Extension Range Cattle Research and Education Center and Betsey Boughton of Archbold Biological Station, reports that up to 90% of carbon storage in grazing lands are located underground. By storing carbon in their roots, grasses can help regulate levels of carbon dioxide in the atmosphere. Greenhouse gases, which include carbon dioxide, methane, and nitrous oxide, have always existed in the atmosphere, but since the US Industrial Revolution, greenhouse gases have been released at a higher rate. According to Boughton, these gases are essential for our atmosphere, but as they build up, it’s like they are wrapping a warm blanket around the earth.

“Imagine yourself in a nice comfortable jacket, and you’re not too hot. But then you start to put on more layers; eventually you get uncomfortable and want to take those off. Sequestering carbon, removing carbon from the air, is a way to take those layers off,” Boughton said.

In agriculture, the carbon cycle occurs naturally, and sequestration is only one step in the cycle. Ruminant animals, including cows, produce carbon dioxide and methane. But cows are grazing on ranches that have pastures, wetlands, and woodlands, and those ecosystems that the animals live and range on absorb carbon too.

Highlands County is home to Archbold Biological Station’s Buck Island Ranch, a 10,500-acre working ranch in Lake Placid, Florida. The scientists at Buck Island Ranch have been studying carbon since 2010, initially to see if the ranch was a source of carbon, meaning they emit more than they take in, or a carbon sink, meaning they absorb more than they take in. After a couple decades of research by multiple scientists, recent modeling has shown that in four out of the six years, the ranch was a carbon sink and on average, the ranch ended up being a net carbon sink.

Grazing practices are key to this process. When cows graze on grass, it stimulates root growth by removing some of the plant’s leaves, increasing the land’s capacity to store carbon. Conversely, without grazing, plants may invest more energy in above-ground growth at the expense of root development, leading to less soil carbon storage. According to Boughton, if you remove grazing from a pasture, then grasses start to disappear and shrubs take over, and these shrubs invest in the above-ground growth at the expense of root development, leading to less soil carbon storage.

The potential for carbon sequestration is significant in Highlands County, which boasts over 212,000 acres of pastureland.  However, the effectiveness of grazing lands in absorbing carbon varies. Well-managed pastures can sequester more carbon than they emit, while overgrazing can have the opposite effect.

Indicators of a healthy, carbon-sequestering pasture include lush, green grass and robust growth. Conversely, areas with bare soil and unhealthy plants are not as likely to contribute positively to carbon storage.

“If there is bare ground and the plants look unhealthy, the pasture is probably not [healthy],” Boughton said.

Ranchers can implement several practices to enhance carbon sequestration on their lands. The main thing is to not overgraze pastures. Rotational stocking, where a pasture is given a period of rest, may help avoid overgrazing and promote root growth. If rotational stocking isn’t feasible due to just one pasture on the operation, stocking rate should be adjusted to avoid overgrazing.  Other beneficial practices are plant legumes to enrich the soil with nitrogen and utilizing prescribed burns to stimulate plant growth.

In a recent webinar, Silveira said, “practices which increase soil carbon should improve forage production too.”

This can be a win-win for ranchers and the climate: by adopting these strategies, ranchers can improve their pastures while actively contributing to the reduction of atmospheric carbon dioxide, fostering a more resilient agricultural landscape.

This blog is inspired by an article published in the Highlands News-Sun on October 20, 2024.

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