Oklahoma State University multidisciplinary scientists are teaming up to research how cover crops can improve the environmental impacts of cattle foraging.
“We need to find new approaches to beef cattle production systems that are economically beneficial to producers and, ideally, would have an environmental benefit as well,” said Dr. Andrew Foote, associate professor in the OSU Department of Animal and Food Sciences. “The industry is making great progress with improving methane emissions from beef cattle, but we are lacking in improvement with nitrogen emissions.”
Fertilizing crops and cattle foraging on harvested cropland cause methane and nitrogen emissions.
“That’s why we came up with this research project to look at using legume cover crops in the summer to fix nitrogen in the soil to minimize the amount of fertilizer producers need to put down for planting wheat in the fall,” Foote said. “We want to see if we can better use wheat cropland between harvesting winter wheat in the spring and planting it again in the fall. On the economic side, could you get another grazing period over the summer or more hay using these four-season cover crops? Then there is the environmental benefit of fixing the nitrogen into the soil.”
The research team includes Dr. Mary Foltz, assistant professor in the OSU School of Civil and Environmental Engineering, and Dr. Josh Lofton, associate professor and Extension specialist for cropping systems in the OSU Department of Plant and Soil Sciences.
Lofton recently planted legume cover crops in wheat fields to grow over the summer. Legumes place nitrogen into the soil through a symbiotic relationship with the bacteria in their roots.
Foltz’s team is now placing chambers to capture and measure carbon dioxide, methane and nitrous oxide emissions in wheat fields with different combinations of cover cropping, fertilizer and cattle grazing treatments to determine if the cover crops decrease overall greenhouse gas emissions.
“Hopefully, we are going to be able to assess the impact of grazing, cover cropping and fertilizer on these different gas emissions with the biggest focus on nitrous oxide, as it is the most potent of the greenhouse gases,” Foltz said. “The ideal scenario is that applying the cover crops will reduce the dependence on synthetic fertilizers and increase soil stability by decreasing soil erosion.”
Foote said OSU Extension will offer forage analysis to producers using summer cover crops when they provide forage samples, and the group will eventually host field days to demonstrate the research results.
Dr. Amy Hagerman, associate professor in the OSU Department of Agricultural Economics, and Dr. Lixia Lambert, assistant professor in ag economics, will develop a spreadsheet-based budgeting tool to help producers figure out the economics of their production system and how the cover crops could work for them. Lofton will manage the cover crop.
Source : okstate.edu