Manure is considered a complete nutrient source because it contains everything a growing plant requires.
A fundamental question often asked by agricultural producers is how do I value my manure as a nutrient resource? This essential question should be asked by those who have access to manure because it allows a way to quantify the economic value of that material. If this question were directed at commercially produced materials, the answer would be straightforward. With manure, however, a number of parameters need to be considered, including the composition of manure, the source variability, and the need for the nutrients based upon soil-test information.
The first step in valuing manure as a nutrient supplement is to have the material analyzed to determine which nutrients are present and in what amounts. This information, combined with a recent soil analysis, can tell you how much manure should be applied to meet the nutritional needs of a crop.
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