Dairy operations are a major source of ammonia emissions. Studies have shown that bedding material can influence the magnitude of ammonia emissions.

In a laboratory setting, researchers at the U.S. Dairy Forage Research Center in Madison, Wis., analyzed the characteristics of six bedding materials — chopped wheat straw, sand, pine shavings, chopped newspaper, chopped corn stalks and recycled manure solids — and their effect on ammonia emissions from dairy cattle urine. Here are some of the results, as reported in the December 2005 Journal of Dairy Science:

  • Recycled manure solids were the most absorbent bedding material. Sand was the least absorbent.
  • When urine was applied to dry bedding, ammonia emissions over 48 hours were lowest for sand, followed by pine shavings.
  • Ammonia emissions increased linearly with absorbance capacity, and decreased as the density of the bedding materials increased.