The North American Manure Expo, happening August 15 – 16 in Brookings, will feature a tour highlighting how manure is stored and managed on South Dakota swine farms. The expo will also showcase new manure technologies.
“There are a variety of ways that swine manure is stored and applied to fields across the U.S.,” said Robert Thaler, South Dakota State University professor and SDSU Extension swine specialist. “Much of South Dakota and the Midwest store and apply manure using practices that significantly decrease the amount of odor emissions.”
According to Thaler, almost all South Dakota swine farms store manure in deep pits instead of anaerobic lagoons so odor is contained. Using deep pits provides opportunities to use odor-reducing technologies like biofilters, which are a layer of organic material, typically a mixture of compost and wood chips, that convert the odorous air to carbon dioxide and water and remove the majority of odor.
Swine manure is a valuable crop nutrient and when it is stored in pits, the manure keeps its nutrients.
In South Dakota, manure is injected into the ground instead of being sprayed through irrigation systems, which means there is no liquid manure on top of the soil. This practice helps significantly decrease odor emissions. As an additional benefit, manure retains 98 percent of its nitrogen value when injected.
“In South Dakota, we are striving to be good environmental stewards and prevent odor emissions with our agricultural practices and how we manage manure in livestock operations,” said Thaler.
The South Dakota Department of Environment and Natural Resources (SD DENR) regulates how all manure is applied in the state. The state’s swine producers are required to show the SD DENR a three-year manure management plan detailing how they are planning to apply it at agronomic rates. Additionally, each year swine producers must submit manure and soil samples.
“The SD DENR does a really great job of protecting the environment and helping livestock producers,” explained Thaler.
To learn more about the North American Manure Expo, visit manureexpo.org.