Federal researchers have finished a year-long study tracking the amount of greenhouse gases like ammonia and methane emitted from a corporate dairy operation in the Magic Valley. The U.S. Department of Agriculture study is the first to look at greenhouse-type gas emissions from an open air-dairy operation, and researchers say the data will provide a baseline for potential regulations and developing management tools to reduce emissions from dairy farms.

As part of the study, researchers tracked emissions from one Magic Valley dairy farm with more than 10,000 cows, measuring one week each month over 10 months.

Overall, the data showed that the cows generated an average of 3,575 pounds of ammonia, 33,092 pounds of methane and 409 pounds of nitrous oxide daily, the Times-News reported (http://bit.ly/nSs632).

Emissions varied based on time of day and the season, with higher temperatures and winds making gases most potent between the afternoon and mid-evening and higher levels reported in spring and summer, according to the report published last month.

April Leytem, the Agriculture Department Research Service's lead scientist on the project, said the data provides a valuable foundation to make future management and regulatory decisions.


"It's hard to say if the amounts are a lot or too much," Leytem said. "There's nothing out there to compare them too. But what it does do is give an idea of what actually comes off an open-lot dairy operation. The next goal it to how best reduce emissions on these farms."

Previous studies of greenhouse gas emissions on farms focused on five operations that significantly incorporate barns and other buildings, features lacking on many of southern Idaho's airy, wide open dairy operations.

The research has been submitted to the Environmental Protection Agency, which monitors greenhouse gases but has no regulations specific to dairy farms.

The study also received some funding from the Idaho Dairymen's Association, which hopes the results lead to improvements in managing dairy operations to reduce emissions.

"We strongly believe in science," said Bob Naerebout, the dairy association's executive director. "These kinds of studies are well-needed. The data was close to what we expected to find." PD

—AP newswire report; information from The Times-News, http://www.magicvalley.com