By Harold Keener, Fuqing Xu, Mary Wicks
In our February article (https://ocj.com/2021/02/98547/), we discussed how manure storage conditions can affect water soluble phosphorus, a contributor to algal blooms. This month we look at levels of nitrogen (N), phosphorus (P), and potassium (K) in stored manure.
NPK levels in livestock manures
Researchers evaluated NPK levels in stored manure using 2018-2019 data provided by a commercial laboratory. The data consisted of analyses of 55 dairy (milking), 397 poultry (layers) and 501 swine manure samples. Farm names and manure management details were not provided. However, 219 of the swine manure samples, which were provided from 91 contract farms using the same feed formulations and deep pit storage, were evaluated separately for comparison. The data was evaluated on a dry basis for comparison purposes as moisture content affects nutrient levels, with high moisture manure being subject to large errors when converted to a dry basis.… Continue readingRead More »