Getting the Most from Manure - a Ancient Fertilizer in a Precision Age

During the twentieth century, agricultural production strived to achieve increased food production in order to satisfy both local and export demands. In many cases, this led to increased farm sizes and an operational separation of crop and livestock production. Society fears that the trend of increasing centralization and industrialization of agriculture, specifically animal agriculture, has resulted in the concentration of waste products associated with their production (manures, wash-down water, process waters, etc.) over relatively small geographic regions that are spatially segregated from crop production areas. Since the distance that manure can be economically hauled for land application has practical limits, the public fears that this spatial separation between crop and animal production areas could lead to over-application, i.e., in excess of crop nutrient demand, of manures near animal feeding facilities, and thus potentially increase transport of nutrients to ground and surface waters. As such it greater emphasis has been placed on its management. Manure can serve as either a resource that is applied to crops to provide nitrogen, phosphorus, trace nutrients, and build soil organic matter or a waste that the producer must dispose. The perspective of whether manure is a waste or resource is often based on the perception of if the cost to utilize (transport and land apply) the manure as a fertilizer is more or less expensive than purchasing commercial, mineral fertilizers. Here we will take a look at how manure management practices have changed over the years, what this has meant for manure value, and what farmers can do to get more from your manure. Topics will range from storage selection, land application choices, and treatment decisions. Each topic will be examined for the economic consequences and opportunities it offers, its environmental impact, and its feasibility of implementation. We will also look at trends in its use and how discuss how to make it a precision fertilizer.