Manure and Animal Waste Management Program

APPLICATION METHODS

Manure can be applied to land by surface broadcasting using a manure spreader, by irrigation system, or by tank wagon followed by plowing or disking, by broadcasting without incorporation, or by knifing under the soil surface. Maximum nutrient benefit is realized when manure is incorporated into the soil immediately or soon after application. Immediate incorporation of solid manure minimizes nitrogen loss to the air and allows soil microorganisms to break down the organic fraction of the manure. Injecting, chiseling, or knifing liquid manure beneath the soil surface reduces nitrogen losses by volatilization and potential runoff. Incorporation of either solid or liquid manure also reduces odor problems. Nitrogen loss by ammonia volatilization from surface applications is greater on dry, warm, windy days than on days that are humid and/or cold. To prevent local high concentrations of ammonium or inorganic salts which can reduce germination and affect yields, manure should be applied uniformly (See Classification of Irrigation Water Quality and Reclaiming Slick Spots and Salty Soils for salinity related information).

Phosphorus and potassium are not as mobile as nitrogen, but incorporation of manure will minimize phosphorus and potassium losses due to runoff, and increase their agronomic value.