Money in the Pit - The Value of Manure

Whether you are a livestock producer looking to utilize a by-product or a crop producer looking for an economical nutrient source, it is essential to know the nutrient content of your manure to make efficient and effective applications. The nutrient composition of manure can vary greatly depending on the livestock type, diet, and method of storage. A laboratory manure analysis can ensure that application rates are appropriate for maximizing crop yields and minimizing the potential for over or under application of nutrients which can cause yield loss or surface and ground water contamination.

The high cost of transportation and application equipment for manure can sometimes cause us to overlook the benefits of land applying manure. Manure is an excellent source of organic matter which, over time, can improve the physical properties of the soil. However, it is difficult to accurately place a dollar value on this benefit because the economics of organic matter are not  well understood when compared with other inputs of crop production, but by comparing the nutrient content of manure to that of conventional fertilizers, a dollar value can be estimated for the manure.

The following example uses approximate prices for fertilizers of $0.35/lb Nitrogen, $0.35/lb Phosphorus (P2O5), and $0.25/lb Potassium (K2O). We will use the average nutrient analysis for two of the most common forms of manure found in the Eastern Corn Belt to determine a value based on the NPK content.

*Not all N will be plant available in the first year after application. Availability is very dependent on weather and other factors. However, estimated first year availability is provided on the laboratory analysis report.

Application rate determinations should be based using the results of a recent soil analysis, as well as estimated crop removal. Appropriate application rates will not supply nitrogen or phosphorus in excess of crop needs. This means that supplemental applications of conventional fertilizers may be necessary to provide the total nutrient needs for your intended crop. For examples of these calculations and more information regarding manure analysis, please see the  A&L Great Lakes Laboratories Fact Sheet titled Manure Analysis and Interpretations.