In the United States, grass-fed beef producers could reduce their annual greenhouse gas (GHG) emissions by 87.5 percent, according to a recent report by the Union of Concerned Scientists (UCS). Raising the Steaks: Global Warming and Pasture-Raised Beef Production in the United States finds that farmers raising beef entirely on pasture—where all beef cattle spend the first months of their lives—can help mitigate climate change. And the report’s findings may have even greater implications for other countries.
“Livestock contribute a greater share of global warming emissions in parts of the world with lower industrial emissions,” writes Doug Gurian-Sherman, UCS Senior Scientist and author of the report. Andmeat production is growing fastest in the developing world, where smallholder farmers and degraded soils could both benefit from the report’s suggested management practices, including avoiding the overuse of fertilizer and preventing overgrazing to increase soil health and carbon sequestration.
The U.S. beef cattle industry produces 160 million metric tons of GHGs each year. But better management practices could reduce emissions by as much as 140 million metric tons—the equivalent of taking 21 million trucks and cars off the road. One practice the report highlights is planting legumes in pastures.
One legume seems especially promising— birdsfoot trefoil. Birdsfoot trefoil, a yellow plant that looks like some varieties of clover, produces special compounds which beef cattle digest more efficiently than other types of feed. Cattle are flatulent, burping and passing gas as they eat. And because cattle are ruminants, with four stomachs, they produce methane, a GHG that is 23 times more potent than CO2. But when cattle eat birdsfoot trefoil, they digest it differently than other grasses or grain, and produce less methane.
Birdsfoot trefoil also adds nitrogen to the soil, helping improve plant productivity and helping reduce the need for additional artificial fertilizer. Using less nitrogen-based fertilizer helps reduce nitrous oxide emissions. Nitrous oxide is another powerful GHG, 296 times stronger than CO2.
While birdsfoot trefoil reduces GHG emissions, its yields are often low and it is more vulnerable to diseases than comparable crops. “Plant breeders have tried to address several of these drawbacks,” explains Gurian-Sherman, but they need more funding for their research. He suggests that the U.S. Department of Agriculture (USDA) expand research to develop improved varieties of the crop.
The report also calls for the USDA to expand its support of small farmers by encouraging them to use birdsfoot trefoil, as well as other environmentally sustainable practices, with both incentive payments and technical assistance for farmers.
In adopting better management practices, farmers across the world could help fight climate change while increasing the health of their soil. As Gurian-Sherman explains, “better management practices would have a larger impact on heat-trapping emissions if used worldwide.”
By Mara Schechter
Danielle Nierenberg, an expert on livestock and sustainability, currently serves as Project Director of State of World 2011 for the Worldwatch Institute, a Washington, DC-based environmental think tank. Her knowledge of factory farming and its global spread and sustainable agriculture has been cited widely in the New York Times Magazine, the International Herald Tribune, the Washington Post, and
other publications.
Danielle worked for two years as a Peace Corps volunteer in the Dominican Republic. She is currently traveling across Africa looking at innovations that are working to alleviate hunger and poverty and blogging everyday at Worldwatch Institute’s Nourishing the Planet. She has a regular column with the Mail & Guardian, the Kansas City Star, and the Huffington Post and her writing was been featured in newspapers across Africa including the Cape Town Argus, the Zambia Daily Mail, Coast Week (Kenya), and other African publications. She holds an M.S. in agriculture, food, and environment from Tufts University and a B.A. in environmental policy from Monmouth College.
